少妇精品视频一区,国产成人理论在线观看视频,1区2区日韩欧美国产,人妻系列视频无码专区,香蕉本道久久精品,国产亚洲天堂视频无码播放

Commonly used plastic materials suitable for injection molding include PE, PP, PS and other thermoplastics suitable for thermoinjection molding.

PE material: PE, also known as polyethylene, is one of the commonly used polymer materials in daily life. It is widely used in the manufacture of plastic bags, plastic films and milk cans.

PP material: polypropylene. Polypropylene has high crystallinity and regular structure, so it has excellent mechanical properties. The mechanical property value of polypropylene is higher than that of polyethylene, but it is still a low variety in plastic materials, and its tensile strength can only reach 30 MPa or slightly higher level. Polypropylene with larger isotactic index has higher tensile strength, but with the increase of isotactic index, the impact strength of the material decreases, but it does not change when it decreases to a certain value.

PS material: PS is polystyrene.

The above materials are commonly used in injection molding.