聚丙烯保险杠专用料收缩率控制

通过调节原辅材料及成核剂等组分及加入量,可以控制聚丙烯(PP)保险杠专用料收缩率,使保险杠成型脱模容易,装车尺寸匹配。粗细填料配合使用可使PP收缩率控制在0.614%～0.940%,加入成核剂使PP收缩率由1.301%下降到1.138%,功能PP与成核剂协同使用,可使专用料收缩率由单独使用成核剂时的1.007%下降到0.931%。前后保险杠专用料和侧护板专用料的收缩率与进口专用料基本一致。

Control of contraction ratio of PP for automobile bumper

The contraction ratio of the speciality polypropylene (PP) resin for automobile bumper was controlled via adjusting components of the auxiliary materials and their proportion for the sake of making the demoulding easier and making the bumper match with the vehicle in dimension.The contraction ratio of the speciality PP resin could be adjusted in the range of 0.940%-0.614% through a rational combination of the coarse and fine fillers.The contraction ratio of the resin lowered from 1.301% to 1.138% due to the introduction of nucleating agent.When the nucleating agent was applied in combination with functionalized PP,the synergistic effect made the contraction ratio of the resin reduce from 1.007% in the case of using only nucleating agent to 0.931%.The contraction ratio of the speciality resin for front bumper,rear bumper and side protection plate is equivalent to that of the imported resin of same kind.