The key points of the process formula of PVC heat shrinkable film

Key points of the process formula of PVC heat shrinkable film Release time: 2017-02-22 　　 1) PVC heat shrinkable film products are different in soft and hard. Under normal circumstances, the amount of plasticizer in the formula is less than 10PHR (PerHundredResin, which means the number of parts by mass of the formula required per 100 parts by mass of resin) is called hard product; the amount of plasticizer is 10～40PHR PVC products are called semi-rigid products; PVC products with plasticizers exceeding 40PHR are called soft products.　　2) Since PVC is a heat-sensitive plastic, heat stabilizers cannot be used in the formulation. In general PVC formulations, the amount of heat stabilizer is 5-8PHR. If there is less heat stabilizer, it is not enough to prevent PVC from decomposing at the temperature of hot melt molding; if there are more heat stabilizers, it will increase the temperature of hot melt flow.　　3) In order to improve the melt processability of PVC and the melt processability of PVC formulations, processing aids should be added to PVC formulations. Practice has proved that for rigid PVC products, it cannot be melt-molded without processing aids, and for soft PVC products without or lacking processing aids, it is also difficult to mold. The processing aids for PVC are mainly acrylic resin (ACR) which has good compatibility with PVC film, as well as chlorinated polyethylene (CPE), chlorosulfonated polyethylene, methyl styrene polymer, MBS, ABS, etc. Note: The processing aid should not be added too much. If it exceeds 12PHR, it may not be extruded due to low melt viscosity and low friction. Generally, the amount of processing aid is 5-8PHR.　　4) Although PVC itself is not vegetarian, its monomer is very strong. According to the US FDA regulations (also internationally recognized), the content of VCM in PVC resin is less than one part per million before it can be used for food and medicine packaging and directly contact with food and medicine. http://, PVC heat shrinkable film Previous: The protective effect of heat shrinkable film on vegetable transportation