热塑性聚氨酯弹性体与乙华平橡胶共混物的性能

Properties of thermoplastic polyurethane and ethylene-vinyl acetate copolymer blends

将聚酯型和聚醚型聚氨酯弹性体(TPU385E,TPU8685)分别与不同乙酸乙烯酯含量的乙华平橡胶(EVM400,EVM700)进行共混,考察了原料种类、共混比对共混物力学性能和耐磨性的影响。结果表明,随着TPU用量的增加,EVM/TPU共混物的拉伸强度、邵尔A硬度、100%定伸应力和300%定伸应力均提高,扯断伸长率下降;随着EVM用量的增加,EVM/TPU共混物的拉伸强度、邵尔A硬度、100%定伸应力和300%定伸应力均降低,扯断伸长率增大;随着TPU用量的增加,EVM/TPU共混物的耐磨性提高;TPU8685/EVM400共混物具有最大的拉伸强度,TPU385E/EVM700共混物具有最大的扯断伸长率,TPU8685/EVM700共混物具有最好的耐磨性;当2种TPU与EVM400质量比都为50/50时,TPU385E/EVM400的耐磨性最差。

Two kinds of ethylene-vinyl acetate copolymer （ EVM ） with different vinyl acetate （VA） content （EVM 400,EVM 700）and two kinds of thermoplastic polyurethane （ TPU ） （ polyester type TPU 8685 and polyether type TPU 385 E） were mixed respectively. The effects of type and blending ratio of materials on the properties of blends were examined. The results showed that the mechanical properties of blends, such as tensile strength, Shore A hardness and modulus at 100% , modulus at 300% increased with increasing TPU content,except the elongation at break decreased. The mechanical properties went the other way round as the increasing EVM content. The abrasion resistance of blends improved with increasing TPU content. TPU 8685/EVM 400 had the best tensile strength. TPU 385 E/EVM 700 had the best elongation at break. TPU 8685/EVM 700 had the best abrasion resistance. TPU 385 E/EVM 400 （50/50） had the worst abrasion resistance.