タイトルまたは説明

PP is a semi-crystalline materials. To be more rigid than PE and has a higher melting point. As the PP products
Are homo-PP temperature higher than 0 ℃ above is very brittle, and therefore many commercial PP material is added 1 to 4% ethylene random copolymer, or a higher ratio of ethylene content of the block copolymer. PP copolymer-based materials have a lower heat distortion temperature (**0 ° C), low transparency, low gloss, low rigidity, but there is a stronger impact strength. Strength of PP increased with increasing ethylene content. The Vicat softening temperature of **0 ° C and the PP. Surface stiffness and resistance to scratches due to the higher degree of crystallinity of this material is very good. PP does not exist the problem of environmental stress cracking. Typically, the use of glass fiber, metal additives or thermoplastic rubber modified PP. PP turnover MFR range from 1 to *0. Low MFR PP material better impact properties, but the extension of lower intensity. MFR for the same material, the intensity ratio of the copolymer-type were dimer type must be high. , PP contraction due to crystallization rate is very high, typically 1.8 to 2.5%. And the direction of the shrinkage uniformity much better than materials such as PE-HD. Adding *0% glass additives can shrink rate to 0.7%. Homopolymer and copolymer PP materials have excellent resistance to moisture absorption, resistance to acid corrosion, anti-solubility. However, it aromatic hydrocarbons (such as benzene) solvents, chlorinated hydrocarbons (carbon tetrachloride) solvents such no resistance. As PE, PP did not still in the high temperature oxidation resistance.