PVC resin powder is a non-crystalline linear polymer compound. The greater its relative molecular mass, the higher the viscosity. The higher the molecular weight, the higher the tensile strength, impact strength and elastic modulus of the product. However, the resin melt Reduced mobility and plasticity. Therefore, the viscosity number is usually used to express the molecular weight of the polymer and classify the polymer model.

The common PVC resin powder is SG-5, followed by SG-3, SG-7, SG-8, etc. For type 5, the production of type 3 PVC requires a long reaction time, high polymerization temperature, and high requirements for the addition of auxiliary materials. The production cost is 50-100 yuan/ton higher than that of type 5. Type 3 PVC has high purity, few fish eyes, easy blister, high temperature resistance, insulation, and soft product texture. It is mainly used for the production of soft products such as wires and cables, agricultural films, conveyor belts, daily plastic products, etc.