Polypropylene is a thermoplastic resin made by the polymerization of propylene. According to the location of the methyl group into isotactic polypropylene (isotactic, polypropylene), random polypropylene (atactic polypropylene) and syndiotactic polypropylene (syndiotactic, polypropylene) three kinds.
Non-toxic, tasteless, small density, strength, stiffness, hardness, heat resistance are better than low pressure polyethylene, can be used at about 100 degrees celsius. The utility model has good dielectric property and high frequency insulation, and is not affected by humidity, but is brittle at low temperature, has no wear resistance and is easy to be aged. Suitable for making general mechanical parts, corrosion resistant parts and insulating parts. Common acid and alkali and other organic solvents, it almost does not work, can be used for utensils.
Polypropylene has many excellent properties:
1, the relative density is small, only 0.89-0.91, is one of the lightest varieties of plastic.
2, good mechanical properties, in addition to impact resistance, other mechanical properties are better than polyethylene, molding processing performance is good.
3, with high heat resistance, continuous use temperature of up to 110-120 degrees.
4, good chemical properties, almost no water absorption, and most chemicals do not respond.
5, pure texture, non-toxic.
6 、 good electrical insulation.
7. The transparency of PP products is better than that of HDPE products.
It has many advantages, but it also has its disadvantages:
1, products cold resistance, low temperature impact strength.
2, products in use are subject to light, heat and oxygen and aging.
3, coloring is not good.
4. Easy to burn.
5, toughness is not good, high static, dyeing, printing and adhesion is poor.