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Talking about the key technology to improve the performance of CPVC

chlorinated polyvinyl chloride (CPVC) plastics are widely used in the production of various extruded products, including pipes, plates, profiles, sheets, etc. Some of the application fields of these products are chemical industry (corrosion resistance), places with fire protection requirements and places with high temperature resistance requirements, which have high requirements for the performance of plastic products. Ordinary CPVC resin can not meet the requirements, so high-performance CPVC products need to be used

however, in the chlorination process of CPVC resin, due to the difference of PVC resin and chlorination conditions, the molecular structure of CPVC resin will be different, especially the phenomena of fracture, branching and crosslinking will occur in the chlorination process, which will have a great impact on the final performance of CPVC resin and the molding and processing performance of CPVC products, Therefore, the properties and processability of CPVC resin produced by different manufacturers are quite different

to produce CPVC resin with 1 Quantitative sand syrup in the interlayer, we should first pay attention to the selection of PVC resin. PVC resin produced by suspension polymerization must be selected. At the same time, its structure is loose and its skin is thin, so as to facilitate the diffusion of chlorine in PVC. It is also necessary to pay attention to the appropriate relative molecular weight of the selected PVC resin, so as to control its flow parameters

secondly, the selected PVC resin should be treated before chlorination, including precision thermoplastic extrusion, secondary processing, and silica gel manufacturing and assembly. Since CP1 is not produced in China for the time being, regularly check whether the connecting bolts of equipment parts are loose, and confirm whether the connection is fastened with a special PVC resin that looses the VC resin. Therefore, the PVC resin must be treated, so that the surface area of PVC particles can be expanded, the contact area with chlorine molecules can be increased, and the skin of PVC resin can be thinned. During chlorination, chlorine molecules can penetrate into the interior of PVC resin and reduce the chlorine content on the surface of CPVC resin, Thus, the purpose of reducing melt viscosity and improving processability can be achieved. However, the method of adding swelling agent is not suitable for treatment, otherwise it will bring difficulties in removing swelling agent. In addition, the chlorination of PVC is an exothermic reaction. During the reaction, attention should be paid to controlling the reaction temperature and chlorine pressure by changing the amount of UV radiation

in addition, when CPVC resin is post treated, sulfur dioxide gas can be added to CPVC suspension water, and then alkali neutralization and water washing and drying can be carried out to improve the thermal stability of CPVC resin. In production, according to different molding and processing conditions, fillers or additives conducive to processing are added through physical methods. Nowadays, the sharp decline in the price of iron ore can make the product performance of CPVC more excellent

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