What kind of PVC resin raw material should be used for the production of PVC heat shrinkable film?

The selection of PVC resin is the key to the production of PVC heat shrinkable film, and the resin that is easy to plasticize and has good comprehensive properties should be selected. As far as the molecular weight of the resin is concerned, the general molecular weight increases, the thermal stability of the product, the calendering, tensile strength, impact strength and other properties of the film will be improved to varying degrees, that is, the physical properties of plastic products will be improved.

However, the mass of the molecule is not as large as possible, if the mass of the molecule is too large, heat shrinkable film plasticization temperature will increase, the fluidity and ductility of the resin will deteriorate, and PVC heat shrinkable film will cause difficulties to the thermal stability system and secondary blowing. According to experience, the selection of PVC-SG5 and PVC-SG6 resins can meet the requirements of heat shrinkage of products. PVC resin is required to have high whiteness and uniform particle size distribution. Before feeding, the PVC resin and the high-mixed material should be sieved twice respectively to reduce the crystal point and impurities of the product.