Shanghai Daoqin Plastics Co., Ltd.

        如题, “TPE overmolding PC is 何会破裂”, this 论题, 本身就 has different understanding. is TPE overmolding separation 发生破裂 also is PC部 separation 发生破裂? small is, use to issues is PC made parts 裂口居 more.

        1.PC parts 裂口(破裂)

         for engineering plastics comparison 熟悉 人士想必都知道, PC(polycarbonate (PC))出现 cracking issues is very Common. PC made parts easy 出现裂口 issues, main/primary is made parts in internal stress 致. PC材 material in molding 时发生 by separation orientation, molding cooling rear, due to in property 差 苯 ring structure, separation understanding orientation non difficult. therefore, PC made parts in molding 时, understanding orientation measures 处理不当, mold temperature degree 设置偏 low, cooling holding pressure time and other, can let separation 子进行充 separation and understanding orientation, molding rear products in internal stress, internal stress to 一定程 degree (large cracking force), PC made parts 就会发生裂口.

        当TPE, TPR二次 injection molding overmolding PC parts 时, due to PC parts internal in relatively large internal stress, this type of internal stress bad function rigid good in overmolding TPE时显现出. or in use TPE overmolding 时, TPE overmolding separation relatively large, in overmolding molding 时TPE包覆层会发生 shrinkage, meanwhile PC parts thick degree also relatively thin, TPE 包覆层 shrinkage will for internal stress function to 推波助澜 function, from 而导致PC made parts cracking.

         solution countermeasures: PC parts molding amount using/adopting high mold temperature, 适当延 long holding pressure and molding cooling time, amount decrease/reduce or remove internal stress.

        2.TPE/TPR包覆层 cracking

        TPE/TPR overmolding PC, TPE包覆层破裂(裂口), this type of 情况, usually is in overmolding molding time rear 出现. TPE,TPR裂口 causes, main/primary is TPR,TPE resistant aging property relatively 差, time 久, material aging cracking 致.

         solution countermeasures: using/adopting resistant aging property excellent TPE,TPR product grade, improves material resistant aging cracking property can.