Shanghai Daoqin Plastics Co., Ltd.

1） temperature degree melt temperature degree θR and injection molding parts mold temperature degree θM rise high make orientation degree decline. this is is: temperature degree rise high rear, although has melt deformation and flow, orientation degree has can can increase large, and meanwhile, polymer understanding orientation can force growth more fast, function 之结果, is understanding orientation effect/influence advantages, therefore orientation degree reduce. 2） injection pressure and holding pressure force improve/increase injection pressure and holding pressure force can increase large melt in force and speed rate, has accelerated orientation process, make orientation degree and products density improve/increase. 3） gate time melt mold cavity flow rear, in long time inner separation hot still comparison 剧烈, already flow orientation structure mono very can can by understanding orientation. is, using/adopting large gate 时, melt in gate in cooling relatively slow, gate relatively 晚, flow process will 会延时, from can in 一定程 degree upper 补偿因 separation hot 运动而引起 understanding orientation, especially is in gate 附近, orientation non significantly. 4） injection molding parts mold temperature degree injection molding parts mold temperature degree relatively low 时, polymer large separation 子 运动容 easy by 冻结, understanding orientation can force decrease small, toward degree increase large. 5）充模 speed degree about/regarding speed degree for process effect/influence, can separation is fast speed and slow speed 充模两 types 情况讨论. ① fast speed 充模时 情况: fast speed 充模时, speed function, products table/sheet 层附近 can to high degree orientation, internal is temperature degree decline ratio positive 常充模时 slow more, therefore understanding orientation can force reinforcement, toward degree ratio table/sheet 层附近 light micro. ② slow speed 充模时 情况: slow speed 充模时, melt and interface （ runner and mold cavity table/sheet and other ） 接触 time long, relatively more hot amount by injection molding parts mold belt/tape 走, in injection temperature degree lower and fast speed versus ratio, large separation 子松弛 time shrink short, understanding orientation can force decline, orientation degree improve/increase. another, slow speed 充模时往往 also need relatively large injection pressure, orientation degree also will therefore 而进一步 improve/increase. comprehensive upper types 情况, can to and generally versus 反 结论, in same injection temperature degree lower, injection molding product internal orientation 而言, slow speed 充模会 ratio fast speed to comparison strong/high orientation structure. however, products table/sheet 层附近 orientation 而言, still is speed degree fast orientation degree high. remove above types effect/influence orientation external factors outer, polymer physical properties for orientation has effect/influence. 例如, polymer specific heat capacity and crystallization hot large 时, make cooling speed degree decrease slow, understanding orientation can force reinforcement, orientation degree decrease small.