Polypropylene can be classified into homopolypropylene (PP-H), block copolymer polypropylene (PP-B) and random copolymer polypropylene (PP-R) according to the molecular structure. The differences in the structure of these three materials give them different application characteristics and therefore have different uses. PP-R is obtained by copolymerization of propylene monomer and a small amount of ethylene monomer under heat, pressure and catalyst. The ethylene monomer is randomly and randomly distributed into the long chain of propylene. The random addition of ethylene reduces the crystallinity and melting point of the polymer, improves the impact of the material, long-term hydrostatic pressure resistance, long-term heat-resistant oxygen aging, and tube processing. PP-R molecular chain structure, ethylene monomer content and other indicators have a direct impact on the long-term thermal stability, mechanical properties and processing properties of the material. The more random the distribution of ethylene monomer in the propylene molecular chain, the more obvious the change in polypropylene properties. PP-H is polymerized from a single propylene monomer, and does not contain ethylene monomer in the molecular chain. Therefore, the molecular chain has a high degree of regularity, so the material has high crystallinity and poor impact performance. In order to improve the brittleness of PP-H, some raw material suppliers also use polyethylene and ethylene-propylene rubber blending to improve the toughness of materials, but they cannot solve the long-term heat stability of PP-H. performance. Compared with PP-R, the ethylene content in PP-B is relatively high, generally 7-15%, but the probability of connecting two ethylene monomers and three monomers in PP-B is very high, so the explanation Since the ethylene monomer is only present in the block phase, the degree of regularity of the PPH is not obtained. Pvc Self-adhesive Floor Stickers pvc self adhesive flooring,peel and stick vinyl floor stickers,removable vinyl floor stickers,PVC floor glue floor sticker,pvc adhesive floor wallpaper JIANGSU ARTSTYLE DECORATION MATERIALS CO..LTD , https://www.jsadpvcwallpaper.com