Manufacturing technology of high temperature cooking packagi

The main raw material of cooking grade CPP film is block copolymer impact polypropylene. Its performance requirements are as follows: Vicat softening point temperature should be higher than cooking temperature; haze should be as small as possible (because the haze of block copolymerization is relatively large); impact resistance; medium resistance; fish eye and crystal point should be as few as possible.

 

 

 

 

There are few domestic copolymers, so it is difficult to develop domestic block copolymers. Due to the high technical requirements and high cost of film grade block copolymerized impact polypropylene, some domestic manufacturers are trying to use high heat sealing temperature binary heat sealing polypropylene and injection molding block copolymer impact resistant polypropylene to replace the film grade block copolymer impact polypropylene.

 

 

 

When the binary heat sealing polypropylene with high heat sealing temperature is used, the heat sealing temperature and thermal strength are no problem, the haze is also very good, and the fish eye and crystal point are few, but the tensile strength, impact resistance, medium resistance, elongation at break and other performance indicators may be almost the same. When using injection grade block copolymer impact polypropylene, the impact resistance and medium resistance are OK, but fish eye and crystal are good The tensile strength, elongation at break, haze and other performance indicators may be poor.