PP板是一种半结晶性材料。它比PE要更坚硬并且有更高的熔点。由于均聚物型的PP温度高于0C以上时非常脆，因此许多商业的PP材料是加入1^4%乙烯的无规则共聚物或更高比率乙烯含量的钳段式共聚物。

共聚物型的PP材料有较低的热扭曲温度(100C) 、低透明度、低光泽度、低刚性，但是有有更强的抗冲击强度。PP的强度随着乙烯含量的增加而增大。PP的维卡软化温度为150°C。由于结晶度较高，这种材料的表面刚度和抗划痕特性很好。PP 不存在环境应力开裂问题。通常，采用加入玻璃纤维、金属添加剂或热塑橡胶的方法对PP进行改性。PP 的流动率MFR范围在1 ~40。低MFR的PP材料抗冲击特性较好但延展强度较低。

对于相同MFR的材料，共聚物型的强度比均聚物型的要高。由于结晶，PP 的收缩率相当高，-般为1。8 2。5%。并且收缩率的方向均匀性比PE-HD等材料要好得多。加入30%的玻璃添加剂可以使收缩率降到0。7%。均聚物型和共聚物型的PP材料都具有优良的抗吸湿性、抗酸碱腐蚀性、抗溶解性。然而，它对芳香烃(如苯)溶剂、氯化烃(四氯化碳)溶剂等没有抵抗力。PP也不象PE那样在高温下仍具有抗氧化性。PP board is a semi crystalline material. It is harder than PE and has a higher melting point. Because homopolymer PP is very brittle when the temperature is higher than 0C, many commercial PP materials are irregular copolymers with 1 ^ 4% ethylene or clamp copolymers with higher ethylene content.


Copolymer PP material has lower heat distortion temperature (100C), low transparency, low gloss and low rigidity, but has stronger impact strength. The strength of PP increases with the increase of ethylene content. The Vicat softening temperature of PP is 150 ° C. Due to its high crystallinity, this material has good surface stiffness and scratch resistance. PP has no environmental stress cracking problem. Usually, PP is modified by adding glass fiber, metal additive or thermoplastic rubber. The flow rate MFR of PP ranges from 1 to 40. PP material with low MFR has better impact resistance, but lower tensile strength.


For materials with the same MFR, the strength of copolymer type is higher than that of homopolymer type. Due to crystallization, the shrinkage of PP is quite high, - generally 1. 8 2。 5%。 And the directional uniformity of shrinkage is much better than that of PE-HD and other materials. Adding 30% glass additive can reduce the shrinkage to 0. 7%。 Homopolymer and copolymer PP materials have excellent moisture absorption resistance, acid-base corrosion resistance and solubility resistance. However, it has no resistance to aromatic hydrocarbon (such as benzene) solvents and chlorinated hydrocarbon (carbon tetrachloride) solvents. PP is not as antioxidant as PE at high temperature.