What material is the packing belt made of?
Polypropylene is a thermoplastic resin made by the polymerization of propylene. According to the location of the methyl group into isotactic polypropylene (isotactic, polyprolene), random polypropylene (atactic polypropylene) and syndiotactic polypropylene (syndiotactic, polypropylene) three kinds.The arrangement of methyl groups on the same side of the molecular backbone is called isotactic polypropylene. If the methyl group is arranged in random order on both sides of the backbone, it is called atactic polypropylene, and when the methyl group is arranged alternately on both sides of the backbone, syndiotactic polypropylene is called. In general industrial polypropylene resins, the isotactic structure is about 95% and the remainder is atactic or syndiotactic polypropylene. Industrial products are based on isotactic substances. Polypropylene also includes copolymers of propylene with a small amount of ethylene. Usually translucent, colorless solid, odorless, non-toxic. The melting point can be as high as 167 DEG C because of the highly crystalline structure. Heat resistance and corrosion resistance, products can be steam disinfection is its outstanding advantages. Small density, is the lightest general plastic. The disadvantages are low temperature resistance, low impact and easy aging, but can be overcome by modification.
The straps are made of PP and PET, two plastic mixes. ?The difference between machine and hand is that the thickness is different, and the requirement of machine is higher.Production process is: plastic melt - - tape - forming - cooling - winding - Packaging - storage is probably the case.
The copolymer type PP material has lower thermal deformation temperature (100 DEG C), low transparency, low gloss and low rigidity, but has stronger impact strength, and the impact strength of PP increases with the increase of ethylene content. The softening temperature of VEKA at PP is 150 DEG C. Because of its high crystallinity, the surface stiffness and scratch resistance of this material are very good. There is no environmental stress cracking in PP.The melt mass flow rate (MFR) of PP is usually at 1~100. The low MFR PP material has better impact resistance, but its strength is lower. For the same MFR material, the impact strength of copolymer is higher than that of homopolymer. As a result of crystallization, the shrinkage of PP is quite high, generally 1.6~2.0%.
