高光泽PPS 6465A62日本宝理---PPS molding conditions:
1 pre drying
In order to improve the appearance of the products and preventsalivation, pre drying at 140 ℃ for 3 hours or 120 ℃ for 5 hours isstill needed, although durafide has weak hygroscopicity.
In order to prevent bridging during drying, it is suggested topre dry at 105 ℃ for 5 hours according to the specific conditionsof the grade.
Due to the strong hygroscopicity of carbon fiber, the carbonfiber reinforced grades (2130a1, 7140a4, etc.) especially need tobe pre dried.
As far as natural color is concerned, in order to obtain morestable hue, the drying conditions should be kept uniform.
2 injection molding machine
In order to prevent tarnishing, the injection molding machinewith balanced injection weight and molding machine capacity shouldbe selected.
Common open nozzle can be selected, but in order to preventsalivation, stop valve can also be used sometimes. In addition, thebarrel and screw should be made of anti friction and anti-corrosionmaterials. The common standard barrel and screw sometimes haveobvious corrosion and friction, so the use should be fullynegotiated with the molding machine manufacturer.
3 molding conditions
The range of molding conditions of durafide is shown in Figure2-1. In order to reduce flash, the barrel temperature should beraised and the injection pressure should be reduced.
高光泽PPS 6465A62日本宝理--设定成型条件时的的注意事项：
(1) 机筒温度
过度降低料斗下的机筒温度时，机筒和螺杆摩擦将趋于增大。
如果流动性方面没有问题，则小幅降温将有助于减少滞留变色。特别是进行非黑色成型品的成型时zui好设为300-320℃。
(2) 模具温度
模具温度对特性的影响很大。
从成型品外观、高温使用时的尺寸稳定性、耐热性以及耐蠕变性来看，模具温度zui好高于130℃而不要低于120℃。
(3) 注射压力
通常zui好采用30～100MPa的注射压力。为了减少飞边，建议进行低压成型。
(4) 注射速度
为了获得良好外观，应进行高速注射。不过，高速注射容易导致成型品翘曲和烧焦，因此只要能够达到外观良好，则无需过度使用高速注射。
(5) 背压
为使计量保持稳定，建议将背压设为2～5MPa。计量不稳定时可将背压小幅提高至8～10MPa。
(6) 螺杆转速
通常以40～100rpm为宜。转速zui好不要超过200rpm，否则会导致玻纤切断和树脂发热。
(7) 机筒内滞留
即使DURAFIDE长时间滞留在机筒内，其粘度也不会大幅增加。由此可见使用热流道是有效的。
