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Chlorinated polyethylene (CPE) is a chlorinated modification product of high-density polyethylene (HDPE). As a processing modifier for PVC, the chlorine content of CPE should be between 35-38%. Due to its excellent weather resistance, cold resistance, flame resistance, oil resistance, impact resistance (CPE is an elastomer), and chemical stability, as well as its good compatibility with PVC, CPE has become the most commonly used impact toughening modifier in PVC processing. The performance of CPE is determined by two factors: 1. Molecular Configuration of HDPE Due to the different process conditions during the polymerization reaction of PE, there are certain differences in the molecular configuration and properties of its polymer HDPE. The properties of CPE after chlorination of HDPE with different properties also vary. CPE manufacturers must choose suitable HDPE special powder resins in order to produce qualified CPE resins. 2. Chlorination conditions, i.e. chlorination process CPE, as a PVC processing modifier, is usually formed by chlorination reaction using aqueous suspension chlorination method. The key conditions of this chlorination process are light energy, initiator dosage, reaction pressure, reaction temperature, reaction time, and neutralization reaction conditions. The principle of PE chlorination is relatively simple, but the chlorination mechanism is more complex. Due to the relatively small investment in equipment for producing CPE, many rudimentary small CPE production plants are already scattered throughout China. This not only causes pollution to the ecological environment, but also is one of the important reasons for the instability of CPE quality. At present, there are a large number of low-quality CPE on the market. Generally, there are two types of low-quality CPE. One is due to some production plants not having the technical conditions and outdated chlorination processes. Another method is to mix a certain amount of calcium carbonate or talc powder in CPE to engage in unfair competition. For the first type of low-quality product, users only need to identify the manufacturer to prevent use, but for the second type of low-quality CPE, many people do not have enough understanding of it. As is well known, the prices of calcium carbonate and talc powder are relatively low, usually between 400-500 yuan/ton, while the price of CPE is generally between 8500-9500 yuan/ton. Some unscrupulous manufacturers mix low priced substances into CPE and sell them at slightly lower prices than qualified products to win market share. Even some manufacturers purchase cheap agglomerated CPE from CPE production plants, which are crushed and then mixed with a certain amount of calcium carbonate or talc powder. After repackaging, they sell it at a lower price (lower than the normal CPE price), engaging in unfair competition to seek improper benefits. Usually, the price of this type of CPE ranges from 7000 to 8000 yuan/ton, and even worse, it is sold at a price of 5000 to 6000 yuan/ton. In the processing of PVC, these inferior CPE are used as modifiers for PVC processing. In order to achieve the purpose of impact resistance and toughening of PVC products, the amount of CPE will inevitably increase, which will lead to an increase in plasticization time, a decrease in equilibrium torque, and an increase in the time to achieve equilibrium torque. All of these will result in a decrease in the overall performance of the product and an increase in the scrap rate. Therefore, whether using cheap but low-quality CPE reduces or increases production costs is self-evident!

The vertical thickness deviation of PVC sheet is large ① The temperature control of the barrel is unstable, resulting in unstable melt flow rate. The temperature of the barrel should be adjusted to stabilize it. ② The unstable screw speed leads to unstable extrusion volume. The process parameters of the extruder should be adjusted to ensure stable extrusion. ③ The roller speed in the three roller calender is unstable. The speed of the three roller calender should be adjusted. ④ The traction speed is unstable, fluctuating fast and slow. The traction speed should be adjusted to ensure smooth operation. Uneven lateral thickness of PVC sheet ① The design of the molding mold is unreasonable, and the fabric flow in the cross-section is uneven. The mold should be modified to ensure even discharge from the mouth mold. ② The adjustment of the gap between the mold lips is unreasonable and uneven. The middle gap should be slightly smaller than the gap on both sides. ③ The gap deviation between the three rollers of the three roller calender is relatively large, and the gap between the three rollers should be made even. ④ The height selection and processing of the three rollers are unreasonable. The height of the roller surface should be appropriately adjusted. The surface of PVC sheet is rough and lacks luster ① Rough or sticky material on the three roll working surface. The working surface of the three rollers should be cleaned and polished to achieve a smooth surface. ② The roller temperature of the calender is too low, and the temperature of the three rollers should be appropriately increased. ③ The surface of the mold lip is not smooth and should be cleaned. ④ The filter screen is broken and should be replaced with a new one. The surface of the board has horizontal lines ① Uneven mixing of materials causes fluctuations in extrusion volume. It is necessary to switch to uniformly mixed materials and adjust the process parameters of the extruder to ensure good plasticization of the materials and even extrusion volume. ② The barrel temperature fluctuates significantly. The temperature control system of the machine barrel should be checked and adjusted to ensure the accuracy of temperature control. ③ The speed of the three rollers is unstable or there are scratches on the roller surface. The speed of the three rollers should be adjusted to ensure smooth operation; Replace the damaged roller or repair the surface of the roller. ④ The traction speed is unstable or the traction roller pressure is insufficient. The traction speed and tension of the traction roller should be adjusted to ensure smooth traction of the sheet metal. Longitudinal lines on the surface of the board ① The extrusion temperature is too low, resulting in poor plasticization of the melt. The body and nose temperature should be appropriately increased The gap between the mold lips is too small. It should be appropriately increased. ②The opening of the mold lip is generally equal to or slightly smaller than the thickness of the sheet, which is expanded after extrusion and stretched to the required thickness. ③ The traction speed is too fast. It should be slowed down appropriately. The traction speed should be slightly faster than the extrusion speed. Warping unevenness ① Improper control of roller temperature in the calender, especially when the temperature of the middle and lower rollers is too low. The roller temperature should be controlled within an appropriate range. ② The contact surface between the two ends of the board and the air is too large, and the cooling speed is too fast. The cooling speed is also fast at the thinner parts of the board. When forming, the board bends towards the part that cools first, generating internal stress. In order to reduce internal stress during molding, it is necessary to cool as evenly as possible and reduce stretching. bubble ①: The raw materials are damp and the moisture content exceeds the standard. The material should be kept low in moisture, and the body and nose temperatures should be too high, causing material decomposition. The processing temperature should be appropriately reduced. Surface black or discolored stripes and spots ① The temperature of the machine head is too high, causing the material to overheat and decompose. The head temperature should be appropriately reduced. ②There are dead corners inside the nose of the machine, causing the decomposition of stagnant materials. The machine head should be cleaned to eliminate dead corners. ③ There are impurities blocking the nose of the machine, causing stagnation

How to improve the hardness of the PVC pipe produced if it cannot meet the standard? Mainly considering raw materials and formulas. Please refer to the following for details: 1. The precipitation volume of filling material (calcium powder) should preferably be within 2.6-3.0. To balance both hardness and tear strength, calcium powder should not exceed 25 parts. In addition, an appropriate amount of nano calcium can be added to improve the strength; 2. The selection of stabilizers is crucial. Stabilizers (lead salt stabilizers, calcium zinc stabilizers, etc.) should have good thermal stability and stable internal and external lubrication balance. Do not use stabilizers that are too cheap 3. If the stability is insufficient, a small amount of metal soap can be compensated; 4. The amount of CPE used should not be too large, as excessive CPE usage can affect the hardness of the pipe; CPE should be selected with high molecular weight, standard chlorine content, no more than 35%, and no residue; 5. Lubricants cannot be used too poorly, they must be good, and PE wax is the worst for external lubrication. The total dosage is about 1.5 parts, not too much, so that when the product deforms under external forces, the PVC molecular chain connection is not easily damaged; 6. In terms of modification, CPE+ACR system, ACR+MABS system, or CPE+MABS system can be selected. 7. Titanium dioxide can affect tear strength, so it is recommended to choose a fine one. We have done chemical products for nearly 30 years. Our main products include PVC RESIN, CPE, STABILIZER, TIO2, PE WAX, PARAFFIN WAX etc.

PVC plastic is a multi-component plastic, and different additives can be added according to different uses. Due to different components, PVC products exhibit different physical and mechanical properties, which are suitable for different applications. The proportion of PVC plastic pipes in plastic pipes is relatively large. RPVC pipes are made by mixing PVC resin with stabilizers, lubricants, and other additives, and then extruding them into pellets using an extruder. They can also be extruded into shape using powder materials in one go. RPVC pipes have good chemical corrosion resistance and insulation, mainly used for conveying various fluids and as wire sleeves. RPVC pipes are easy to cut, weld, bond, heat and bend, making installation and use very convenient. SPVC pipes are made by adding a large amount of plasticizer, a certain amount of stabilizer, and other additives to PVC resin, and then extruding them into shape after granulation. SPVC pipes have excellent chemical stability, excellent electrical insulation, and good flexibility and coloring properties. This type of pipe is often used instead of rubber pipes to transport liquids and corrosive media. It is also used as cable sleeves and wire insulation pipes. We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2, PE WAX, PARAFFIN WAX, STEARIC ACID, STEABILIZER ETC.

We have done chemical products for over 30 years. Our main products include PVC RESIN, CPE, PE WAX, STEARIC ACID, PARAFFIN WAX, STABILIZER ETC.

PVC storage continues to decrease slightly compared to the previous month As of now, the social inventory of PVC in China is 458000 tons, a decrease of 0.95% month on month and a year-on-year increase of 23.55%; Among them, in the East China region, there were 395100 tons, a decrease of 1.35% month on month and a year-on-year increase of 27.16%; In South China, there were 62900 tons, an increase of 1.62% month on month and 4.83% year-on-year. International PVC Resin market demand slows down The demand for PVC Resin in India has slowed down, and most customers have already completed their stocking needs for September. Moreover, downstream pipeline demand is currently tepid, leading to a decrease in enthusiasm to continue hoarding inventory at current prices. At the end of the month, the demand for foreign trade terminal orders was weak. As early expectations did not materialize, the performance of industrial fundamentals was weak, market prices fluctuated and decreased, and the atmosphere for foreign trade exports slowed down. The bearish future prices exacerbated the downward trend in foreign trade export prices; During the week, relevant financial policies were released, and the macro environment for commodities was positive. The market volatility rebounded, but market transactions remained flat with limited upside potential. Domestic calcium carbide prices continue to rise This week, the domestic calcium carbide market still saw a narrow upward trend, with mainstream trade prices in the Wuhai region rising to 3250 yuan/ton, and overall supply remains tight. The production enterprises started this week with instability, and there were occasional power restrictions in the Greater Wuhai region, resulting in unstable supply. Junzheng's maintenance is approaching its end, and the external sales of calcium carbide have decreased. Downstream, there is a regional shortage of goods. The price of raw material orchid charcoal has increased, presenting a situation of easy to rise but difficult to fall, providing certain cost support. Next week, the market is expected to enter a consolidation phase. Firstly, in terms of supply, there are plans to resume production of calcium carbide furnaces that have been discontinued in the early stage. Secondly, the high price of PVC has fallen, which has hindered the upward trend under cost pressure. Thirdly, the cost side of blue charcoal prices has increased, providing support for the price side. With the increase in supply, the market's supply shortage has eased to some extent, but the supply is still tight in the short term. Overall, the scale of PVC maintenance in China is gradually decreasing, and supply is gradually recovering. There are currently no intensive maintenance plans in other regions of Asia; There has been no increase in orders from domestic downstream product companies at the end of the month, and there is sufficient inventory of products. Demand has not improved. From the perspective of foreign trade, there is a delay in demand in India and Southeast Asia, and the expected prices for October are low; From the perspective of market supply and demand, there has been no improvement in the slow increase in supply and demand, and the competitive pressure in the foreign trade export market has increased. The domestic cost side remains strong supported by high energy levels, providing good support for the bottom of the market. We have done chemical products for over 30 years. Our main products include PVC RESIN, CPE, PE WAX, STEARIC ACID, PARAFFIN WAX, STABILIZER ETC.

During the extrusion process of PVC foam board, the problems encountered can be basically classified into four categories, One is the stability issue Secondly, the issue of melt strength The third issue is lubrication The fourth issue is decentralization These four types of problems, especially the first three, are mutually constrained and cross influenced, and sometimes it is difficult to distinguish them immediately from surface phenomena. It is necessary to observe and analyze the root cause of the problem in order to fundamentally solve it. Insufficient stability can affect the entire board surface, resulting in yellowing and high brittleness of the foam sheet. Insufficient melt strength can lead to large foam pores and long longitudinal bubbles in foam sheets. The direct way to determine whether the melt strength is insufficient is to press the sheet wrapped on the middle roller with your fingers behind the three rollers. When the melt strength is good, you can feel elasticity when pressing. If it is difficult to bounce after pressing, it indicates poor melt strength. Due to significant differences in screw structure and cooling methods, it is difficult to determine whether the temperature is reasonable. Generally speaking, within the allowable load of the extruder, it is better to have a lower temperature in the 3-5 zone. In order to obtain uniformly foamed products in foamed pipes, it is also necessary to ensure that PVC materials have good melt strength. The foaming agent developed by the company is designed to solve the problem of foaming products, which can effectively improve the quality of foaming pipes. Lubricants are divided into external lubricants and internal lubricants. External sliding is beneficial for demolding and is beneficial for the smoothness of the sheet surface. If there is too little external sliding, the temperature in zone 5 of the extruder is difficult to control and easy to rise, which can lead to high temperature of the confluence core, large bubbles, string bubbles, yellowing and other problems in the middle of the sheet, and the sheet surface is also not smooth; If there is too much external sliding, the precipitation will become severe, manifested in the structure inside the mold and the precipitation on the surface of the board. It can also be manifested as some individual phenomena that move back and forth irregularly on the board surface. Internal sliding is beneficial for plasticization and the fluidity of the melt. Insufficient internal sliding makes it difficult to control the thickness of the plate surface, manifested as the thickness in the middle and thin on both sides of the plate; The phenomenon of high temperature of the confluence core is prone to occur due to excessive internal sliding. Poor dispersion can lead to uneven surface of the board. Process temperature control issues: The four issues mentioned above are fundamental, fundamental, and deep-seated issues. Compared to the above four issues, process temperature control is much more intuitive and is a surface issue, but poor temperature control can trigger the emergence of fundamental problems. Increasing the processing temperature will reduce the material stability time and result in stability issues; The original lubrication balance will be disrupted. Generally manifested as insufficient external lubrication, especially in the later stage, it is necessary to increase the amount of external lubrication added; An increase in temperature can also lead to a decrease in melt strength, an increase in foam pores and a decrease in the number of foam pores in the foam sheet, making the sheet brittle and prone to fracture; The increase in temperature reduces the strength of the melt and also reduces the viscosity of the melt. The viscosity decreases and the shear dispersion ability decreases. For screws with weak dispersion ability, uneven dispersion may sometimes occur. We deal with pvc resin for more than 30years. Except pvc resin, we also have its relative additives, such as CPE, PE WAX,PARAFFIN WAX,TIO2, STEARIC ACID,STABILIZER,CACO3 and so on. One-stop purchase can save your time.

Heat stabilizer is one of the indispensable main auxiliaries for PVC processing. The number of parts used for PVC heat stabilizer is small, but its role is huge. The use of heat stabilizer in PVC processing can ensure that PVC is not easy to degrade and relatively stable. The commonly used heat stabilizers in PVC processing include basic lead salt stabilizer, metal soap stabilizer, organotin stabilizer, rare earth stabilizer, epoxy compound, etc. The degradation mechanism of PVC is complex, the action mechanism of different stabilizers is different, and the stabilization effect is also different. PVC stabilizer, action mechanism and application 1 Lead salt stabilizer Lead salt stabilizers can be divided into three categories: (1) Pure lead salt stabilizer is mostly a basic salt containing PbO; (2) The heat stabilizer with lubricating effect is mainly the neutral and basic salt of fatty acid; (3) Composite lead salt stabilizer, and solid and liquid composite stabilizer containing a synergistic mixture of lead salt and other stabilizers and components. Lead salt stabilizer has strong thermal stability, good dielectric properties, and low price. The reasonable ratio of lead salt stabilizer and lubricant can widen the processing temperature range of PVC resin, and the quality of processed and post-processed products is stable. It is the most commonly used stabilizer at present. Lead salt stabilizer is mainly used in hard products. Lead salt stabilizer has the characteristics of good heat stabilizer, excellent electrical performance and low price. However, lead salt is toxic and can not be used in products that contact with food, nor can it make transparent products, and it is easy to be contaminated by sulfide to generate black lead sulfide. 2 Metal soap stabilizer Stearic acid soap heat stabilizers are generally prepared by saponification of alkaline earth metals (calcium, cadmium, zinc, barium, etc.) with stearic acid, lauric acid, etc. There are many kinds of products, each with its own characteristics. Generally speaking, lubricating stearic acid is better than lauric acid, and the compatibility with PVC lauric acid is better than stearic acid. Metal soaps can absorb HCl, and some varieties can replace the Cl atom of the active site with fatty acid radical through the catalysis of metal ions, so they can play a different degree of thermal stability on PVC. In PVC industry, there is rarely a single metal soap compound, but usually a compound of several metal soaps. The common stabilizer is calcium zinc soap. According to Frye-horst mechanism, the stability mechanism of calcium/zinc composite stabilizer can be considered as follows: first, zinc soap reacts with allyl chloride on the PVC chain, and then calcium soap, zinc soap and chlorine chloride react to form unstable metal chlorides. At this time, the auxiliary stabilizer, as the intermediate medium, transfers the chlorine atoms to the calcium soap to regenerate the zinc soap, delaying the formation of zinc chloride which can promote the dehydrochlorination. Calcium and zinc stabilizers can be used as non-toxic stabilizers in food packaging, medical devices and drug packaging, but their stability is relatively low. When calcium stabilizers are used in large amounts, their transparency is poor and they are easy to spray frost. Calcium and zinc stabilizers generally use polyols and antioxidants to improve their performance, and transparent calcium and zinc composite stabilizers for hard pipes have appeared in China. 3 Organotin stabilizer Alkyl tin in organotin is usually methyl, n-butyl and n-octyl. Most of the products produced in Japan are butyl tin, and octyl tin is more common in Europe. This is the standard non-toxic stabilizer approved in Europe, while methyl tin is used more in the United States. There are three main types of organotin stabilizers commonly used: (1) Aliphatic acid salts mainly refer to dibutyltin dilaurate, di-n-octyltin dilaurate, etc; (2) Maleate salts mainly refer to dibutyltin maleate, bis (monobutyl maleate) dibutyltin maleate, di-n-octyltin maleate, etc; (3) Mercaptans, of which bis (thiocarboxylic acid) ester is the most used. Organotin heat stabilizer has good performance and is a good variety for PVC hard products and transparent products. In particular, octyltin has almost become an indispensable stabilizer for non-toxic packaging products, but its price is relatively expensive. Organic tin heat stabilizer (tin mercaptoacetate) has a good stabilizing effect on PVC. Especially the liquid organotin stabilizer can be better mixed with PVC resin than the solid heat stabilizer. The organotin stabilizer (tin mercaptoacetate) can replace the unstable Cl atoms on the polymer, making the PVC resin have long-term stability and initial color retention. The stability mechanism of tin mercaptoacetate was proposed: (1) S atom can replace unstable Cl atom, thus inhibiting the formation of conjugated polyolefins. (2) As a product of PVC thermal degradation, HCl can also accelerate the formation of conjugated polyolefins. Tin mercaptoacetate can absorb the HCl produced. 4 Rare earth stabilizer Rare earth heat stabilizers mainly include organic weak acid salts and inorganic salts of light rare earth lanthanum, cerium and neodymium, which are rich in resources. The types of organic weak acid salts include rare earth stearate, rare earth fatty acid, rare earth salicylate, rare earth citrate, rare earth laurate, rare earth octanoate, etc. The preliminary study on the action mechanism of rare earth stabilizer is as follows: (1) The special electronic structure of rare earth lanthanide elements (2 electrons in the outermost layer and 8 electrons in the secondary layer, with many empty orbits) determines that the energy difference of their empty orbits is very small. Under the action of external thermal oxygen or polar groups, the outer or secondary outer electrons are excited, which can coordinate with the unstable Cl on the PVC chain, and can form a coordination complex with the hydrogen chloride decomposed during the processing of PVC, At the same time, there is a strong attraction between rare earth elements and chlorine elements, which can control the free chlorine element, thus preventing or delaying the automatic oxidation chain reaction of hydrogen chloride and playing a role of thermal stability. (2) The rare-earth multifunctional stabilizer can physically absorb the oxygen in PVC processing and the ionic impurities contained in PVC itself, and enter the lattice hole of the rare-earth multifunctional stabilizer to avoid their impact and vibration on the parent C-Cl bond. Therefore, the activation energy of HCl removal from PVC can be increased by the action of rare earth multifunctional stabilizer, thus delaying the thermal degradation of PVC plastics. (3) Suitable anion groups in rare earth compounds can replace allyl chloride atoms on PVC macromolecules, eliminate this degradation weakness, and achieve stability. There are many studies on rare earth stabilizers in China. In general, the stability effect of rare earth heat stabilizers is better than that of metal soap stabilizers. It has good long-term thermal stability, and has extensive synergistic effects with other stabilizers. It has the advantages of good tolerance, free from sulfur pollution, stable storage, non-toxic and environmental protection. In addition, rare earth elements have a unique coupling effect with CaCO3 and promote the plasticizing effect of PVC, so the amount of CaCO3 can be increased, the use of processing aid ACR can be reduced, and the cost can be effectively reduced. The stabilizing effect of rare earth on PVC is characterized by its unique synergistic effect. The proper coordination of rare earth with some metals, ligands and co-stabilizers can greatly improve the stability.

Generally, most of the plastic masterbatches are added calcium carbonate, but they must be calcite crystal ores. Because the ores are different, although they are all calcium carbonate, some can be produced. Some cannot be produced. Talcum powder and calcium carbonate can be used. In terms of cost, calcium carbonate is lower than talcum powder. In terms of production technology, calcium carbonate is easier to process than talcum powder. Talcum powder and calcium carbonate shall be added to the polypropylene granule for packing belt, and the ratio is: polypropylene: talcum powder: calcium carbonate=70:25:5. For woven bags, calcium carbonate should be used. The addition amount can reach more than 30 portions. Pay attention to the temperature during processing. 1. Talc powder and calcium carbonate are used for filling, and their main purposes are: 1. increase dimensional stability (i.e., reduce shrinkage), 2. increase the rigidity of the material, 3. increase the heat resistance of the material, 4. reduce the cost of the material, etc., but there are also some defects: 1. increase the density, 2. poor use, impact toughness, 3. material luster has decreased. 2. Talc powder and calcium carbonate have the same particle size difference, generally 300 mesh, 600 mesh, 800 mesh, 1250 mesh and 2500 mesh, and of course, there are finer ones. Generally, 800 mesh and 1250 mesh can be selected for plastic, which can make the performance/price ratio the highest. 3. The price of talc powder fluctuates. Generally speaking, it is not a big problem to determine the price according to the number of items. For example, the price of 800 items is between 700 and 850 yuan, and that of 1250 items is between 1000 and 1280 yuan. It is abnormal for the price to be too high or too low. About the different use of talc powder and calcium carbonate: 1. The shape of talc powder is flaky, so it has higher rigidity, dimensional stability, heat resistance and good reinforcement effect. 2. Calcium carbonate is generally granular, so its rigidity and other aspects are not as good as talc powder, but its price is lower, and its whiteness is high, and its impact toughness of plastics is small. 3. Talc powder has nucleating effect on polypropylene, while calcium carbonate has no obvious effect on this aspect. 4. Calcium carbonate can generally be divided into light calcium carbonate and heavy calcium carbonate, but talc powder has no such distinction. Talc powder is ground from natural minerals.

PVC is widely used in shoe materials because of its high performance-price ratio. However, white soles often change color and turn yellow, especially in high temperature weather in summer. In order to prevent the soles from changing color and turning yellow, we should first identify the reasons for the color and turn yellow, and then apply the right medicine to the case. First, precipitation. Because there are a lot of plasticizers (generally 60~100PHR) added to the shoe material, but the compatibility of liquid plasticizers (especially chlorinated paraffin, liquid paraffin, white oil, etc.) with PVC is not very good. When the temperature rises, it is easy to precipitate to the surface of the shoe material, resulting in yellowing of the sole. Solution: use plasticizers with high molecular weight and good compatibility with PVC, such as polyester plasticizers; Use high mesh calcium powder to increase dispersion and oil absorption value; Reduce the use of stearic acid soap and stearic acid lubricant, and replace with polyol ester lubricant; Use some type 2 and 3 resin powder to increase oil absorption value; Add ACR resin to improve the uniformity of plasticization, make the surface compact and reduce the exudation. Second, lead pollution. When the temperature is high in summer, lead salt stabilizers, especially powdered trisalt and bisalt, are used. When the temperature is high, lead pollution or sulfur pollution, yellowing and discoloration will occur when sulfur elements (such as packaging cartons) are encountered. Solution: use lead salt stabilizer for PVC shoes or calcium and zinc stabilizer for soles; Reduce exposure to sulfur; Reduce storage temperature, etc. Third, the stability is insufficient. Insufficient stability of PVC will lead to the process from white to yellow to red to brown, and then the conversation will turn black. Stability is divided into light stability, thermal stability and oxygen stability. Solution: replace with high-quality stabilizer or increase the amount of stabilizer; Add an appropriate amount of ultraviolet light absorber; Add antioxidants, etc. PVC foam sole reference formula Formula 1: PVC 100, DOP 80-85, light calcium 60-65, AC 0.5-0.6, foaming regulator about 2.0, lead salt compound stabilizer (TG-38A) 3.8, PE wax 0.6, stearic acid 1.0, titanium dioxide 2.5 Formula II: PVC 100, DOP 90, light calcium 70, AC 0.8, foam conditioner 2.0 or so, lead salt stabilizer (TG-38A) 4.0, PE wax 0.5, stearic acid 1.2, titanium dioxide or toner appropriate Formula III: PVC 100, DIBP 85, light calcium 60, AC (TG-75) 0.5, foam conditioner 2.0 or so, calcium zinc composite stabilizer 4.0, PE wax 0.3, stearic acid 0.5, titanium dioxide or color powder appropriate.

CPE is chlorinated polyethylene, which is prepared by chlorination of special high-density polyethylene (HDPE). It is the product of partially replacing the hydrogen atom on the molecular chain of HDPE with chlorine atom. It is white powder after drying and non-toxic. CPE molecular formula: CH2-CHCl-CH2-CH2] n English abbreviation: CPE or CM chlorinated polyethylene (CPE) is a saturated polymer material. characteristic Because CPE molecule does not contain double chain, it has good weather resistance, flame resistance and thermal stability, which is superior to PVC, low cost and excellent performance. Soluble in aromatics and halogenated hydrocarbons, insoluble in aliphatic hydrocarbons, decomposed above 170 ℃, and released hydrogen chloride gas. It has stable chemical structure, excellent aging resistance, flame resistance, cold resistance, weather resistance, free coloration, chemical resistance, ozone resistance, electrical insulation, and good compatibility and processability. It can be mixed with PVC, PE, PS and rubber to improve its physical properties. Three factors affecting CPE performance First, the type of PE used ---- CPE obtained from high molecular weight polyethylene has high viscosity and tensile strength, but the adhesion between CPE and PVC resin is low. CPE obtained from low molecular weight polyethylene has low viscosity and tensile strength, and CPE obtained from high density polyethylene has good heat resistance. Second: the size of raw material particles ----- the size is too small to form jelly or agglomerate CPE, and the chlorine distribution is uneven when the particle size is too large, which is difficult to dissolve in organic solvents, and the particle size range is 0.1-200 μ M is the best. Third, the chlorination degree of CPE - when the chlorine content is below 25%, it has poor compatibility with PVC and cannot be used as a modifier; When the chlorine content is more than 40%, it has good compatibility with PVC and can be used as solid plasticizer, not as impact modifier; CPE with chlorine content of 36-38% has good elasticity and compatibility with PVC, so it is widely used as PVC impact modifier. At present, CPE with 35% chlorine content is the most widely used. CPE with about 35% chlorine content has low crystallinity and glass transition temperature, good rubber elasticity, and suitable compatibility with PVC. It is widely used as an impact modifier for PVC hard products. Production technology of CPE CPE is mainly produced by suspension method, which can be divided into aqueous phase method and hydrochloric acid phase method. The water phase method has high utilization rate of chlorine gas, stable chlorine content in the product, but serious equipment corrosion and large amount of three wastes. The hydrochloric acid phase method is the most advanced production method, with short process knowledge, stable product quality and low three wastes. Selection of CPE impact modifier 1) Domestic CPE models are generally identified by such as 135A, 135B, 140B, 239C, etc. The first digit 1 and 2 represent the residual crystallinity (TAC value), 1 represents the TAC value of 0-10%, 2 represents the TAC value of>10%, the second and third digits represent the chlorine content, such as 35 represents the chlorine content of 35%, and the last digit is the letter ABC, which is used to represent the molecular weight of raw PE, A is the largest, and C is the smallest. 2) Effect of molecular weight: CPE type A material has the largest molecular weight, and its melting viscosity is also large. Its viscosity is the best match with PVC. It has the best dispersion effect in PVC and can form an ideal network dispersion form. Therefore, CPE type A material is generally selected as the modifier of PVC. 3) TAC value: TAC value represents the content of PE crystal and amorphous form in CPE molecule, which reflects the uniform distribution of chlorine atoms on CPE molecule to a certain extent. A large TAC value indicates that PE chain segment has many crystals, while PE chain segment has poor compatibility with PVC. A small TAC value indicates that PE and PVC have good compatibility. Generally, CPE with a TAC value less than 5 is selected as the impact resistance agent. Effect of CPE addition on PVC The impact strength of PVC increases rapidly with the addition of CPE when the amount of CPE is less than 10 minutes, but the impact strength of PVC increases little when the amount of CPE is further increased. Therefore, as an impact resistant agent, the appropriate amount of CPE is 8-10 phr. At the same time, with the increase of CPE, the tensile strength of PVC blends continues to decline, and the elongation at break increases. If the toughness is expressed by the product of tensile strength and elongation at break, it is obvious that the toughness of PVC will obviously increase with the increase of CPE addition. Some literatures believe that when the content of CPE exceeds the saturation solubility in PVC, CPE is separated from PVC, forming a micro-phase separation structure of PVC as sea and CPE as island, which greatly improves the impact strength of PVC. Others believe that when the content of CPE exceeds 6 parts, CPE can form a network in the formula, which plays an impact modification role, but when the content of CPE is low (such as 1 part), it can neither form a network in the formula system, It will not precipitate beyond its saturated solubility in PVC, and it has little impact modification effect in the formula. Effect of CPE on processing properties of PVC When the number of CPE added is less than 5, it is delayed plasticizing, and at 5, it has no effect on the plasticizing of the formula system. It plays a role in promoting plasticization when CPE exceeds 5 parts. With the increase of CPE, the plasticization time of the formula becomes shorter and shorter, the maximum plasticization torque and balance torque increase, and the plasticization temperature gradually decreases. The chlorine content of CPE is 35%, and there are two chain segments in its structure: one is the chlorine chain segment whose hydrogen atom is replaced by chlorine atom, which has a strong structure and is similar to PVC with good compatibility; the other is the PE chain segment whose hydrogen atom is not replaced by chlorine atom, which has a weak structural polarity and poor compatibility with PVC, which plays an external lubrication role between PVC and can delay the plasticization of PVC. The glass transition temperature of CPE is about 10 ℃, while that of PVC is 80 ℃. Under the test conditions, CPE shows the trend of softening and plasticizing earlier and slightly higher viscosity than PVC. When the amount of CPE added is small, the total amount of polar chain segments with good compatibility between CPE and PVC is small, the external lubrication of PE chain segments is dominant, and the plasticizing of the system is delayed. With the increase of CPE, the early softening and plasticizing of a large number of CPE molecules and higher viscosity promote the viscosity of the whole formula system to increase, At this time, the effect of CPE on the viscosity of the whole material overcomes the external lubrication effect of PE chain segment in its structure, so that the whole formula system begins to plasticize at a lower temperature, and plays a role in promoting the material plasticization. Application of CPE 1. Application of CPE plasticized PVC waterproof coiled material in waterproof coiled material. Due to the excellent characteristics of CPE, the tensile strength of the new product has increased by 80%, the tear strength has increased by 50%, and its mechanical weather resistance, low temperature resistance, aging resistance and other properties have been improved. It is well received by the construction department (including 10% - 15% of CPE). The neoprene CPE waterproof coiled material and neoprene CPE styrene-butadiene rubber waterproof coiled material have the advantages of high strength, high elasticity, high extensibility, corrosion resistance, high temperature resistance, cold resistance, aging resistance, flame retardancy, etc. They are the new generation of ideal waterproof materials with a broad market. 2. The production of plastic doors and windows by blending CPE and PVC has greatly improved their elasticity, toughness and low-temperature performance, and good weather resistance, heat resistance and chemical stability. This kind of plastic doors and windows is cheap, corrosion-resistant, colorful and bright, and has outstanding advantages over aluminum alloy doors and windows. It has largely replaced aluminum doors and windows, and the market will be more and more broad. 3. Application in wire and cable sheath: The addition of CPE can improve its negative combustion performance, anti-aging performance and physical and mechanical properties. It can also be used as the main body to make wire and cable coating materials with excellent performance. 4. Adding CPE elastomer into PE can improve its printability, flame resistance and flexibility. After adding 5% CPE into HDPE, the adhesion between the mixture and the ink increased by three times. After adding CPE into PE hose for mining, it has good flame retardancy. 5. Application of CPE as the main material: It can be used to manufacture hose with good performance of oil resistance, acid resistance, bending resistance, ozone resistance and freon resistance, and is suitable for manufacturing hydraulic hose, cooler hose, fuel hose, etc. The imitation leather sole made with CPE as the main body has excellent performance. 6. Application of CPE in drive belt: It can manufacture heat-resistant drive belt, and has good resistance to non-polar solvent swelling. The adhesion and flex times of the drive belt made of CPE/NR/SBR and rubber are higher than those of the drive belt made of pure rubber, thus extending the service life, and improving the shrinkage of the pure rubber after rolling, and the poor permeability of the rubber in the textile during rolling The forming belt embryo is easy to bond and other process properties, which improves the weather resistance and flame resistance of the drive belt. 7. CPE mixed with other rubbers: CPE has good compatibility with a variety of rubbers. CPE blended with NR has better wear resistance, fatigue resistance, acid resistance and alkalinity resistance. Compared with NBR and CR, CPE has a lower price. CPR and NBR can be used together to improve oil resistance and excellent heat and oxygen aging resistance, which can be used to manufacture oil resistant rubber tubes and oil resistant sealing products.

1. Stabilizer The most widely used stabilizers in PVC foaming products are lead salt stabilizer and calcium zinc stabilizer. With the increasingly stringent requirements of environmental protection and the higher performance-price ratio of calcium zinc stabilizer, the application of calcium zinc stabilizer has become more and more extensive. Insufficient stabilizer, yellowing of board surface, large brittleness of paste and products, reduced strength and low foaming rate; If there is too much stabilizer and the foaming agent decomposes in advance, the gas will overflow from the feeding hole and vacuum hole, and the cavity structure will crack or shrink; 2. External lubricant The most widely used external lubricants on foaming products generally include paraffin wax and PE wax, which are easy to precipitate, so PE wax is generally used. The external slip is insufficient, and the temperature in zone 4 and zone 5 of the extruder is not easy to control, and it is easy to overheat. The plate surface has blisters, blisters, yellowing, and rough surface; The friction shear heat increases, causing material decomposition, yellowing and paste on the plate surface; Excessive external sliding and poor plasticization lead to scaling in the inner cavity of the mold and precipitation on the surface of the product, which is prone to leucorrhea, uneven wall thickness and irregular movement of some symptoms on the surface; 3. Internal lubricant Common internal lubricants include stearic acid, 60, monoglyceride, 316, etc. Insufficient internal lubrication, poor dispersion of materials, uneven plasticization, difficult to control the thickness of the product, thin middle and both sides of the foam board, white band, adhesion to the mold cavity and local overheating may also occur; Too much internal lubrication, brittle foaming products, reduced heat resistance, and changed to external lubrication under a certain temperature and melt pressure, resulting in unbalanced lubrication;

As we all know, plastics will be driven by mechanical force and stirred by shear force during heating, melting and molding. Plastics and plastics, plastics and machinery will generate various frictions, which will generate heat. Excessive friction will generate friction heat, which will lead to scorching and bubble phenomena when the temperature of the plastic core cannot be derived. Therefore, it is generally necessary to add lubricant in the plastic processing process to reduce the attraction between polymer molecules, so as to improve its fluidity, and reduce the adhesion of product surfaces and the mutual adhesion of plastics. In addition to improving the fluidity, the lubricant can also play the role of melting accelerator, anti adhesion agent, anti-static agent, smoothing agent, etc. After understanding the significance of its existence, let's take a look at its classification and functions? Lubricants mainly include internal lubricant and external lubricant 1. Main functions of internal lubricant and external lubricant The main function of the internal lubricant is to weaken the interaction between the internal chain segments of the polymer, make the polymer molecules slide easily, and improve the fluidity of the polymer melt. This lubricant is compatible with the polymer molecules and can be evenly distributed around the polymer molecules, such as the common processing aid: stearic acid The main function of the external lubricant is to make the surface of the product shiny, easy to demould, and prevent adhesion on the surface of the product. They have poor compatibility with the resin, and cannot be evenly dispersed around the resin molecules, and cannot be dispersed inside. Generally, the amount of external lubricant should not be too much, which may cause frost or stickiness on the surface. E.g. polyethylene wax 2. Main functions of internal lubricant and external lubricant The function of internal lubricant is mainly to weaken the attraction between macromolecular chains, make them slide easily, and reduce the interface friction; The powder resin is stably gel; Reduce the melt viscosity of the resin and improve the fluidity of the resin; Improve production capacity and reduce mechanical load. The main function of the external lubricant is to reduce the aging and decomposition of the resin due to local overheating; Improve the surface gloss of plastic products; Make the products easy to demould and prevent the products from adhering to the mold surface. We have done chemical products for over 30years. Our main products include pvc resin, CPE, TIO2, PARAFFIN WAX, PE WAX, STABILIZER ETC.

PVC cable compound is a kind of particle prepared by mixing, kneading and extruding PVC based resin, adding stabilizer, dioctyl phthalate, diisodecyl phthalate, dioctyl terephthalate, trioctyl trimellitate and other plasticizers, calcium carbonate and other inorganic fillers, additives and lubricants. PVC cable material has high withstand voltage and insulation resistance, but its dielectric constant and dielectric loss are large. Therefore, it is generally used as the insulation layer of low voltage and medium high voltage cables. PVC plastic is also widely used as the protective material of wires and cables due to its flame retardant, oil resistant, corona resistant, chemical resistant and good water resistance. Heat resistant, cold resistant, oil resistant, flame-retardant, super soft, non-toxic and environment-friendly flame retardant PVC cable compounds can be manufactured by adding special performance additives or modifiers to meet the needs of special wire and cable products. The quality of PVC cable material is determined by the brightness of the cable material, and the main influencing factors are as follows: Plasticizer: The straighter and longer the molecular chain, the brighter. For example, 1030 is brighter than TOTM, and DOA is brighter than DOP. Stabilizer: It also has an effect. Generally, those with fast gel formation are brighter. Process: of course, the high extrusion temperature is brighter than the low temperature, and the good mixing effect is brighter than the poor mixing effect of black powder (such as 50L, etc.): do not exceed 0.8PHR, otherwise, be careful to granulate, and it will not be bright. PVC polymerization degree: the lower, the brighter, S-60 is brighter than S-70. Calcium carbonate: the finer the particle size, the brighter the surface is. Light calcium is brighter than heavy calcium, ultra-fine light calcium is brighter than ordinary light calcium, such as CCR501 is brighter than white cherry blossom. Needless to say, the truth of other inorganic functional fillers such as antimony trioxide or aluminum hydroxide is the same. The less the fillers are, of course, brighter than the more fillers. So these things have less energy, and can use liquid instead of powder. The brightness of PVC cable material determines the quality of products. Therefore, many cable material manufacturers start from improving the brightness of cable material to make their best efforts to produce high-quality products.

This week (2022.10.31-2022.11.04), the mainstream ex factory price and receiving price of calcium carbide were mainly adjusted below, and the production enterprises had poor delivery. The price of calcium carbide generally fell at the weekend, and this week continued the trend of decline at the weekend to maintain a weak operation, with the price dropping frequently.First of all, some upstream manufacturers resumed operation of their devices, and the manufacturer's inventory pressure increased. Some manufacturers lowered their ex factory quotations to promote shipment and reduce inventory; Secondly, the downstream PVC in some areas has entered the maintenance stage. Some devices of BDO enterprise have been stopped for maintenance or agent replacement. The downstream demand has shown a decreasing trend as a whole, which has a certain price depressing behavior for calcium carbide enterprises. The main downstream PVC has different purchase prices for calcium carbide. The traders reduced the market price to facilitate the transaction. At present, from the perspective of calcium carbide market fundamentals, the market price may still have a downward trend. From the perspective of supply, the starting of calcium carbide manufacturers in some regions has increased to a certain extent, and the manufacturer's inventory has increased; From the perspective of demand, both downstream PVC and BDO enterprises' devices have been overhauled. At present, the downstream market is entering the slack season of demand, and the purchasing enthusiasm is not high. Although the downstream PVC market has reversed in the week, it has not played a significant role in supporting the calcium carbide market as far as the current situation is concerned. The PVC market trend may have a certain impact on the calcium carbide market in the later stage, so it is necessary to pay attention to the PVC market trend. The semicoke market on the raw material side stabilized after a short fall, which generally supported the cost side of calcium carbide. In the current situation, the blocked raw material transportation is the biggest obstacle to the market. On the whole, the supply and demand of calcium carbide market are weak at present, the upstream shipment and transportation continue to be under pressure, the regional arrival of goods in the downstream is uneven, and the demand is expected to decrease. Under the contradiction between supply and demand in the market, it is expected that the short-term calcium carbide price will continue to decline, and it is necessary to pay attention to whether the PVC market will continue to maintain the upward trend. We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2,PE WAX, PARAFFIN WAX, STABILIZER ETC.

Today, the mainstream factory price and acceptance price of the domestic calcium carbide market continue to decline, and the supply and demand sides of the calcium carbide market perform generally. The upstream production enterprises are relatively active in shipping, the inventory is at a higher level compared with the downstream demand, the downstream demand is relatively weak, and the market is in a situation where supply exceeds demand. The manufacturers are blocked in shipping, so the factory price is lowered, and the traders reduce the shipping price to promote the transaction. At present, the supply and demand side is weak, basically in a situation of weak supply and demand. The supply side of enterprises in some regions has improved, and some early maintenance devices are expected to recover. The supply side has an increasing trend, while the demand side is not performing well. The downstream PVC has turned from a decline to an increase after a long period of decline in the early stage. Although the market has reversed, from the current feedback of the calcium carbide market, there is no significant support for the calcium carbide market, In addition, the demand for some devices in BDO industry to be shut down for maintenance or agent change is expected to decrease. On the whole, the calcium carbide market is expected to continue to fluctuate and decline in the short term. We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2,PE WAX, PARAFFIN WAX, STABILIZER ETC.

The problems encountered during the extrusion of PVC foam sheets can be basically classified into four categories, First, stability Second, the melt strength Third, lubrication Fourth, decentralization These four types of problems, especially the first three types of problems, will restrict each other and cross affect each other. Sometimes it is difficult to distinguish them immediately from the superficial phenomenon. It is necessary to observe and analyze the problem and find the root cause to fundamentally solve it. Inadequate stability will affect the whole board surface. The board surface will turn yellow and the foam sheet will be brittle. Insufficient melt strength will lead to large foam cell and long longitudinal foam. To judge whether the melt strength is insufficient, the direct method is to press the sheet wrapped on the middle roll with your finger behind the three rolls. When the melt strength is good, you can feel the elasticity. If it is difficult to spring up after pressing, the melt strength is poor. It is difficult to judge whether the temperature is reasonable because the screw structure and cooling mode are quite different. Generally speaking, the temperature in Zone 3-5 should be lower within the allowable load of the extruder. In order to obtain uniform foamed products in foamed pipes, it is also necessary to ensure that PVC materials have good melt strength. The foaming agent developed by the company is developed to solve this problem of foaming products, which can effectively improve the quality of foaming pipes. Lubricants are divided into external lubricant and internal lubricant. The external sliding is beneficial to demoulding and the smoothness of the plate surface. The external sliding is too little, and the temperature in zone 5 of the extruder is difficult to control and easy to rise, which will lead to high temperature of the confluence core, blisters, yellowing and other problems in the middle of the plate, and the plate surface is not smooth; The precipitation will become serious due to more external sliding, which is shown in the structure in the mold and the precipitation on the plate surface due to external sliding, and also in the irregular back and forth movement of some individual phenomena on the plate surface. The inner slip is beneficial to plasticization and melt fluidity. The thickness of the plate is difficult to control if the inner slip is insufficient, which shows that the plate is thick in the middle and thin on both sides; The phenomenon of high temperature of the confluence core is easy to occur due to more internal slip. Poor dispersion will lead to unsmooth plate surface. Process temperature control problems: The four issues mentioned above are fundamental, fundamental and deep-seated. Compared with the above four problems, the process temperature control is much more intuitive. It is a surface problem, but poor temperature control will lead to fundamental problems. When the processing temperature is increased, the material stability time will be reduced, resulting in stability problems; The original lubrication balance will be broken. Generally, the external lubrication is insufficient, especially in the later period, the amount of external lubrication should be increased; The increase of temperature will also lead to the decrease of melt strength, the increase of foam cell, the decrease of foam cell number, and the brittleness and fracture of the sheet; The increase of temperature reduces the melt strength and also reduces the melt viscosity. The reduction of viscosity reduces the shear dispersion ability. For screws with weak dispersion ability, uneven dispersion sometimes occurs. We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2,PE WAX, PARAFFIN WAX, STABILIZER ETC.

CPE, namely chlorinated polyethylene, is prepared by chlorination of special high-density polyethylene (HDPE). It is the product of partially replacing hydrogen atoms on HDPE molecular chain with chlorine atoms. After drying, it is white powder, non-toxic. CPE molecular formula: CH2-CHCl-CH2-CH2] n English abbreviation: CPE or CM chlorinated polyethylene (CPE) is a saturated polymer material. characteristic Because CPE molecule does not contain double chains, it has good weather resistance, flame resistance and thermal stability, superior to PVC, low cost and excellent performance. It is soluble in aromatic hydrocarbons and halogenated hydrocarbons, insoluble in aliphatic hydrocarbons, decomposes above 170 ℃ and emits hydrogen chloride gas. It has stable chemical structure, excellent aging resistance, flame resistance, cold resistance, weather resistance, free coloring, chemical resistance, ozone resistance, electrical insulation, and good compatibility and processability. It can be mixed with PVC, PE, PS, and rubber to improve their physical properties. Three factors affecting CPE performance First, the type of PE used ---- CPE obtained from high molecular weight polyethylene has high viscosity and tensile strength, but the adhesion between CPE and PVC resin is low. CPE obtained from low molecular weight polyethylene has low viscosity and tensile strength. CPE obtained from high density polyethylene has good heat resistance. Second: size of raw material particles ---- gel or agglomerated CPE is easy to form when the particle size is too small, chlorine distribution is uneven when the particle size is too large, and it is difficult to dissolve in organic solvents, and the particle size range is 0.1-200 μ M is the best. Third: The chlorination degree of CPE ---- When the chlorine content is below 25%, the compatibility with PVC is poor, and it cannot be used as a modifier; When the chlorine content is more than 40%, it has good compatibility with PVC, and can be used as a solid plasticizer, not suitable for impact modifier; CPE with chlorine content of 36-38% has good elasticity and compatibility with PVC, so it is widely used as impact modifier of PVC. At present, the most widely used CPE is the one containing 35% chlorine. The CPE containing about 35% chlorine has low crystallinity and glass transition temperature, good rubber elasticity, and suitable compatibility with PVC. It is widely used as an impact modifier for PVC hard products. CPE production technology CPE is mainly produced by suspension method, which is divided into aqueous phase method and hydrochloric acid phase method. The water phase method has high chlorine utilization rate and stable chlorine content in the product, but the equipment is severely corroded and the amount of three wastes is large. Hydrochloric acid phase method is the most advanced production method with short process, stable product quality and low waste. Selection of CPE impact modifier 1) Domestic CPE models are generally identified by 135A, 135B, 140B, 239C, etc. The first digit 1 and 2 indicate the residual crystallinity (TAC value), 1 indicates that the TAC value is 0-10%, 2 indicates that the TAC value is>10%, and the second and third digits indicate the chlorine content. For example, 35 indicates that the chlorine content is 35%, and the last digit is the letter ABC, which is used to indicate the size of PE molecular weight of raw materials. A is the maximum, and C is the minimum. 2) Influence of molecular weight: CPE type A material has the largest molecular weight and large melt viscosity. Its viscosity matches PVC best. It has the best dispersion effect in PVC and can form an ideal network dispersion form. Therefore, CPE type A material is generally selected as the modifier of PVC. 3) TAC value: TAC value indicates the content of PE crystal and amorphous form in CPE molecule, which reflects the uniform distribution of chlorine atoms on CPE molecule to some extent. A large TAC value indicates that the PE chain segment has more crystals, while the compatibility between PE chain segment and PVC is poor. A small TAC value indicates that the compatibility between PE and PVC is good. Generally, CPE with a TAC value less than 5 is selected as the impact agent. Effect of CPE addition on PVC The impact strength of PVC increases rapidly with the addition of CPE when the amount of CPE is less than 10 points, but the impact strength of PVC increases little when the amount of CPE is further increased. Therefore, as an impact resistant agent, it is appropriate to add 8-10 phr of CPE. At the same time, with the increase of CPE, the tensile strength of PVC blends continues to decline and the elongation at break increases. If the toughness is expressed by the product of tensile strength and elongation at break, the PVC toughness will obviously increase with the increase of CPE addition. Some literatures think that when more than 8 portions of CPE exceed the saturated solubility in PVC and precipitate from PVC, forming a micro phase separation structure of PVC as sea and CPE as island, which greatly improves the impact strength of PVC. Others think that when more than 6 portions of CPE are added, a network can be formed in the formula, which plays an impact modification role. However, when the amount of CPE is low (such as 1 portion), a network cannot be formed in the formula system, It will not precipitate beyond its saturated solubility in PVC, and it has little impact modification effect in the formula. Effect of CPE on processing properties of PVC When the number of CPE added is less than 5, the plasticization is delayed, and at 5, it has no effect on the plasticization of the formula system. It plays a role in promoting plasticization when CPE exceeds 5 phr. With the increase of CPE, the plasticizing time of the formula becomes shorter and shorter, the maximum plasticizing torque and balance torque increase, and the plasticizing temperature decreases gradually. The chlorine content of CPE is 35%, and there are two chain segments in its structure: one is the chlorination chain segment whose hydrogen atom is replaced by chlorine atom, which has a strong structure and is similar to PVC with good compatibility; the other is the PE chain segment whose hydrogen atom is not replaced by chlorine atom, which has a weak structural polarity and poor compatibility with PVC, which plays an external lubrication role between PVC and can delay the plasticization of PVC. The glass transition temperature of CPE is about 10 ℃, while that of PVC is 80 ℃. Under test conditions, CPE shows a trend of softening and plasticizing earlier than PVC and a slightly higher viscosity. When the amount of CPE added is small, the total amount of polar segments with good compatibility between CPE and PVC is small, the external lubrication of PE segments is dominant, and the plasticization of the delayed system. With the increase of CPE, a large number of CPE molecules become soft and plasticized in advance and the higher viscosity promote the viscosity of the entire formula system to increase, At this time, the influence of CPE on the viscosity of the whole material overcomes the external lubrication of the PE chain segment in its structure, so that the entire formula system begins to plasticize at a lower temperature, which promotes the plasticization of the material. Application of CPE 1. The application of CPE enhanced PVC waterproof coiled materials in waterproof coiled materials, due to the excellent characteristics of CPE, the tensile strength of the new product has been increased by 80%, the tear strength has been increased by 50%, and its mechanical weather resistance, low temperature resistance, aging resistance and other properties have been improved. It is well received by the construction department (including 10% - 15% CPE). Neoprene CPE waterproof coiled materials and neoprene CPE styrene butadiene rubber waterproof coiled materials have the advantages of high strength, high elasticity, high elongation, corrosion resistance, high temperature resistance, cold resistance, aging resistance, flame retardancy, etc. They are ideal waterproof materials of a new generation and have a broad market. 2. The production of plastic doors and windows by blending CPE and PVC has greatly improved its elasticity, toughness and low-temperature performance, and has good weather resistance, heat resistance and chemical stability. This kind of plastic doors and windows is cheap, corrosion-resistant, colorful and bright. It has more advantages than aluminum alloy doors and windows. It has replaced aluminum doors and windows to a large extent, and the market will become wider and wider. 3. Application in wire and cable sheath: The addition of CPE can improve its cathodic combustion performance, anti-aging performance and physical and mechanical properties. It can also be used as the main body to make wire and cable coating materials with excellent performance. 4. Adding CPE elastomer into PE can improve its printability, flame resistance and flexibility. When 5% CPE was added to HDPE, the adhesion between the obtained mixture and the ink was increased by three times. The PE hose for mining has good flame retardancy after adding CPE. 5. Application of CPE as main material: It can be used to manufacture rubber hoses with good performance of oil resistance, acid resistance, folding resistance, ozone resistance and Freon resistance. It is suitable for manufacturing hydraulic rubber hoses, cooler rubber hoses, fuel rubber hoses, etc. The cow like leather sole made with CPE as the main body has excellent performance. 6. Application of CPE in transmission belt: heat resistant transmission belt can be manufactured, and it also has good resistance to nonpolar solvent swelling. The adhesion and bending times between each adhesive layer of the transmission belt produced with CPE/NR/SBR adhesive are higher than those of the transmission belt made with pure adhesive, thus extending the service life. At the same time, it also improves the large shrinkage of the pure adhesive after calendering, and the poor permeability of the adhesive in textiles during calendering The molding belt embryo is easy to stick, which improves the weather resistance and flame retardancy of the transmission belt. 7. Blending of CPE with other rubbers: CPE has good compatibility with a variety of rubbers. When CPE and NR are blended, their wear resistance, fatigue resistance, acid resistance and alkaline resistance become better. Compared with NBR and CR, the price of CPE is lower. CPR and NBR can be used to make oil resistant rubber hose and oil resistant sealing products because of their oil resistance and excellent heat and oxygen aging resistance. We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2,PE WAX, PARAFFIN WAX, STABILIZER ETC.

The hardness of the PVC pipe can not reach the standard, how to improve it? Mainly from the aspects of raw materials and formula. See the following for details: 1. The sedimentation volume of filler (calcium powder) should preferably be within 2.6-3.0. Both hardness and tear strength shall be considered, and calcium powder shall not exceed 25 phr as far as possible. In addition, appropriate nano calcium can be added to improve the strength; 2. The selection of stabilizer is very important. Stabilizers (lead salt stabilizers, calcium zinc stabilizers, etc.) should have good thermal stability and stable internal and external lubrication balance. Do not use cheap stabilizer, poor 3. If the stability is not enough, a small amount of metal soap can be compensated; 4. The amount of CPE shall not be too large, and excessive amount of CPE will affect the hardness of the pipe; CPE shall be selected with high molecular weight, standard chlorine content, no more than 35%, and no residue; 5. Lubricants shall not be used too badly, but must be good. PE wax is the worst for external sliding. The total dosage is about 1.5 phr, not too much, so when the product is deformed when encountering external forces, the PVC molecular chain connection is not easy to be damaged; 6. In terms of modification, CPE+ACR system, ACR+MABS system or CPE+MABS system can be selected. 7. Titanium dioxide will affect the tear strength, so it should be fine.

The main reason is that the dosage of stabilizer is not enough or grade is not good, should still have the phenomenon of redness. It's possible that a particularly bad stabilizer was used. But most of the cases are lubrication imbalance caused by the problem, lubrication is too little, especially the outer slip is too little, too plasticizing caused by pipe discoloration, brittle... Can add titanium dioxide, see if it can cover, if there is no try to add stabilizer or change, if it is calcium zinc stabilizer should pay more attention to the adjustment of sliding agent. In addition, lubricants affect plasticization, calcium carbonate is added whitening agent, and so on, there is PVC resin, other conditions are the same, with bad PVC will become more yellow, need more stabilizer. In general, will think of the problem of stabilizer, in fact, in the case of sufficient stability, lubrication is also a very important factor. In addition, if the calcium powder is damp, it will also affect the plasticization. The stabilizer is usually the first consideration, but the problem can generally be solved by adjusting the lubrication system properly. Eliminate the problem of stabilizer, then focus on sliding agent, dynamic balance. Stabilizers referred to in the industry generally do not contain antioxidants. But calcium zinc stabilizers generally contain antioxidants. The rutile type has a reddish background, while the anatase type has a bluish background. Rutile is better, but more expensive. Whether rutile type or anatase type titanium dioxide, in the visible wavelength range (400-700nm), their reflectance of light is very high, so they have a good whiteness. But in less than the visible light range such as 300-400 nm UV wavelength range, the performance of the two different crystal types of titanium dioxide is very different. For rutile titanium dioxide (red line) in the UV - A band with strong lethality (350-400nm) it is far lower than the blue titanium dioxide anatase, in other words, its UV absorption rate is significantly higher than the blue titanium dioxide anatase. In this case, it is around the film of organic resin to share the UV light is much less, so the service life of these organic matter is also long. This is why the rutile type of titanium self-powder, as we commonly call it, has much better weather resistance than the anatase type. These properties are innate. In extrusion is the type of titanium dioxide base color affects the color of the product, in the later use, titanium dioxide on ultraviolet absorption of different effects on the weatherability of the product to affect its color. Actually, rutile type titanium white just than sharp titanium type slightly yellow not turn yellow, the problem is stabilizer was more likely, it is possible that the use of the composite stabilizer, the current domestic some manufacturer of composite stabilizer added a large amount of lubricant to reduce cost, reduce the dosage of effective components, stability is slightly less than under the same weight. The temperature is too high, the compression ratio of the mold is too large, the amount of stabilizer added is not enough, the lubrication system has problems, the stability of the resin itself is not enough, the calcium powder tide, the gap between the screw and the barrel has problems, the shear is too large, there are many reasons, but also according to the actual situation!! We have done chemical products for over 30years. Our main products include PVC RESIN, CPE, TIO2,PE WAX, PARAFFIN WAX, STABILIZER ETC.