According to the different application scope, PVC can b […]
According to the different application scope, PVC can be divided into: general-purpose PVC resin, high polymerization degree PVC resin, and cross-linked PVC resin. General-purpose PVC resin is formed by the polymerization of vinyl chloride monomer under the action of initiator; high degree of polymerization PVC resin refers to the resin polymerized by adding chain extender to the polymerization system of vinyl chloride monomer; cross-linked PVC resin is A resin polymerized by adding a crosslinking agent containing diene and polyene to the vinyl chloride monomer polymerization system.
According to the method of obtaining vinyl chloride monomer, it can be divided into calcium carbide method, ethylene method and imported (EDC, VCM) monomer method (the ethylene method and imported monomer method are commonly referred to as ethylene method).
According to the polymerization method, polyvinyl chloride can be divided into four categories: suspension polyvinyl chloride, emulsion polyvinyl chloride, bulk polyvinyl chloride, and solution polyvinyl chloride. Suspension process polyvinyl chloride is the largest variety, accounting for about 80% of the total PVC output. Suspension process PVC is divided into six models according to absolute viscosity: XS-1, XS-2……XS-6; XJ-1, XJ-2……, XJ-6. The meaning of each letter in the model: X-suspension method; S-loose type; J-compact type.
According to the content of plasticizer, PVC plastics are often divided into: non-plasticized PVC, plasticizer content is 0; rigid PVC, plasticizer content is less than 10%; semi-rigid PVC, plasticizer content 10-30%; soft PVC, plasticizer content is 30-70%; polyvinyl chloride paste plastic, plasticizer content is more than 80%.