Shanghai Daoqin Plastics Co., Ltd.

         foaming injection molding for/regarding reduce injection molding raw materials cost and improves products machine strong/high degree has versus large 意义, through use foaming technology injection molding plastics products machine strong/high degree can improves foaming 状态 2-4倍, is types 廉价且 high methods. chemical method foaming process in generate gas main/primary is nitrogen gas, its is oxidation carbon and water separation, and a small amount of other gas 体, 几乎无毒无味, for/regarding product and gas formed 二次污染, is types environmental protection injection molding process.

         due to foaming injection molding process tool has this non more advantages, for/regarding foaming technology utilizing and again development tool has non heavy large 意义, new material for chemical method foaming injection molding principle 进行一 simple 阐述:

         nylon PA12 injection molding foaming

        普通 chemical method foaming injection molding process 包含四 stage/phase:

         foaming agent and raw materials 进行充 separation mixed combined;

         a large amount of bubbles mono speed formed;

         bubbles expand dispersion versus melt combined 贯通;

         foaming agent separation understanding full, product stability 期.

        第一 stage/phase: foaming agent and polymer 进行充 separation mixed combined, in this process in must selection active temperature degree ratio raw materials melt temperature degree more high foaming agent, ensure foaming agent and melt separation uniform mixed combined front 不发生 foaming reaction, improve/increase dispersion 效果;

        第二 stage/phase: temperature degree improve/increase, active foaming agent separation understanding gas 体, through in raw materials in add nucleating agent, promote bubbles formed 效果, nucleating agent generally is using/adopting fine small inert property pellets, carbon acid 钙, high carbon and other and other, high quality nucleating agent has generate high quality bubbles;

        第三 stage/phase: bubbles production, 并开始 melt combined 贯通, expand large gas foam in material inner 联汇贯通. in this process in due to foaming agent ratio/proportion different, generate types 情况, types is in material inner generate versus 连 泡孔, 叫闭孔 foaming;另一 types is formed bubbles 孔, 叫开孔 foaming; if foam made lower, make foam 塌陷;

        第四 stage/phase: foaming separation understanding full rear, foaming reaction 停止, polymer viscosity upper rise, gas again growth, molding solid 化开始. through cooling, crosslinked or other solid methods make polymer viscosity upper rise solid molding.

        整 foaming to molding process its non short, from separation 之一秒 to 几秒, product and foaming different different, through control foaming quality and amount control product quality is foaming injection molding process focus/key point. control process and foaming process for/regarding product quality has non large effect/influence, if rear foaming, formed 泡孔壁 viscosity low, product soft, heavy can can generate 塌陷;凝胶提 front foaming, 则孔壁太 hard, make inner pressure high, easy make 孔壁撕裂, most make product large cracking.