Polypropylene, abbreviated as PP, is a polymer formed by addition polymerization of propylene. It is a white waxy substance with a transparent and light appearance. The chemical formula is (C3H6)n, its density is 0.89 ~ 0.9 1g/cm3, it is flammable, its melting point is 164~ 170℃, it softens at about 155℃, and its service temperature range is-30 ~/kloc. It can resist the corrosion of acid, alkali, salt solution and various organic solvents below 80℃, and can be decomposed under high temperature and oxidation.
Polypropylene is a thermoplastic synthetic resin with excellent properties. It is a colorless and translucent thermoplastic lightweight general plastic. It has chemical resistance, heat resistance, electrical insulation, high strength mechanical properties and good wear resistance. Widely used in the production of clothing and blankets, medical equipment, automobiles, bicycles, parts, transportation pipelines, chemical containers and other fiber products. , also used in food and drug packaging. ?
The use of polypropylene materials
1, machinery and automobile manufacturing parts
Polypropylene has good mechanical properties, and can be directly manufactured or modified to manufacture various mechanical equipment parts, such as industrial pipes, agricultural water pipes, motor fans, capital construction templates, etc. The modified polypropylene can be molded into bumpers, scuff strips, steering wheels, dashboards and interiors. , greatly reducing the weight of the car body and achieving the purpose of energy saving.
2, electronic and electrical industrial devices
Modified polypropylene can be used to make insulating shells of household appliances and liners of washing machines, and is widely used as insulating materials for wires, cables and other electrical appliances. 60-80 parts by weight of polypropylene homopolymer, 20-40 parts by weight of ethylene-vinyl alcohol polymer, and 0/-10 part by weight of compatilizer (reactant of polypropylene maleic anhydride graft and ethylene-vinyl alcohol).
Polypropylene composites blended and refined at 170℃~ 190℃ have high toughness, impact strength as high as 2 10J/m, high gas barrier performance and moisture permeability close to 2000 g micron/(m2 24h). When preparing the barrier film, the traditional film-making process can be used for production, with relatively simple process and low production cost.
3. Construction industry
Polypropylene fiber is the lightest of all chemical fibers, and its density is (0.90~0.92)g/cm3. It has the advantages of high strength, good toughness, good chemical resistance and antibacterial property, and low price. Glass fiber modified polypropylene or rubber and SBS modified polypropylene are widely used to make building engineering templates, and foamed polypropylene can be used to make decorative materials.