According to different application scopes, PVC can be divided into: general-purpose PVC resin, high-polymerization PVC resin, and cross-linked PVC resin. General-purpose PVC resin is formed by polymerizing 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 vinyl chloride monomer polymerization system; cross-linked PVC resin is A resin polymerized by adding a cross-linking agent containing diene and polyene to the vinyl chloride monomer polymerization system.
Based on the method of obtaining vinyl chloride monomer, it can be divided into calcium carbide method, ethylene method and imported (EDC, VCM) monomer method (it is customary to refer to the ethylene method and imported monomer method collectively as ethylene Law).
According to the polymerization method, polyvinyl chloride can be divided into four major categories: suspension polyvinyl chloride, emulsion polyvinyl chloride, bulk polyvinyl chloride, and solution polyvinyl chloride. Suspension polyvinyl chloride is the largest variety in production, accounting for about 80% of the total PVC production. Suspension polyvinyl chloride 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 plasticizer content, PVC plastics are often divided into: unplasticized PVC, the plasticizer content is 0; rigid PVC, the plasticizer content is less than 10; semi-rigid PVC, the plasticizer content is 10-30%; soft PVC, the plasticizer content is 30-70%; PVC paste plastic, the plasticizer content is more than 80%.