变模温与型腔气体反压辅助微孔发泡注塑技术及其产品内外泡孔结构演变

Dynamic Mold Temperature Control and Cavity Gas Counter Pressure Assisted Microcellular Injection Molding and Evolution of Inner and Outer Cell Structure of the Molded Parts

建立了一种变模温和型腔气体反压协同控制的微孔发泡注塑技术,研制了相应的变模温控制系统与型腔气体反压控制系统,构建了变模温与型腔气体反压辅助微孔发泡注塑试验线,并对变模温与型腔气体反压作用下的产品内外泡孔结构演变进行了研究。结果表明,变模温与型腔气体反压辅助工艺单独施加于微孔发泡注塑技术时,对其产品内外泡孔结构均具有双重影响:变模温可以改善产品大部分的表面形貌,但其对填充过程中的熔体发泡影响不大;型腔气体反压可以基本抑制填充过程中的熔体发泡,但却对产品内部泡孔密度有比较明显的降低影响。通过变模温与型腔气体反压的协同控制,可以实现微孔发泡注塑产品表面气泡形貌和内部泡孔结构的良好调控。

A kind of dynamic mold temperature control and cavity gas counter pressure assisted microcellular injection molding technique was established.The corresponding dynamic mold temperature control system and cavity gas counter pressure control system were developed,the dynamic mold temperature control and cavity gas counter pressure assisted microcellular injection molding test line were constructed,and the evolution of inner and outer cell structure of the molded parts were studied.The results show that when the dynamic mold temperature control or cavity gas counter pressure is applied to microcellular injection molding separately,it has double effects on the inner and outer cell structure of the molded parts:the dynamic mold temperature control can improve the most surface appearance of the molded parts,but has little effect on the melt foaming during filling stage;the cavity gas counter pressure can basically inhibit the melt foaming during filling stage,but has a significant effect on reducing the cell density of molded parts.Through coordinated controlling of dynamic mold temperature and cavity gas counter pressure,the inner and outer cell structure of the microcellular injection molded parts can be well regulated.