弹性体和刚性粒子对聚甲醛的增韧改性研究

采用热塑性聚氨酯弹性体（TPU）和刚性粒子纳米二氧化硅(SiO2)对聚甲醛(POM)进行了协同增韧，并通过差示扫描量热仪和扫描电子显微镜等分析了增韧体系的结构和性能。结果表明，TPU/SiO2协同增韧提高了POM缺口冲击强度，且能有效降低传统增韧方法对材料拉伸强度和弯曲模量造成的损失；当POM中单独加入20 %（质量分数，下同）TPU时，POM的缺口冲击强度提高了89 %，拉伸强度和弯曲模量却分别降低了18 %和40 %；单独加入2 % SiO2时，POM的缺口冲击强度仅提高22 %，增韧效果不明显；同时加入20 %的TPU和2 %的SiO2时，POM的缺口冲击强度提高了230 %，拉伸强度和弯曲模量仅分别下降了8 %和13 %。

Study on Toughening Modification of POM with Elastomers and Rigid Particles

The synergetic toughening effect of TPU and nano SiO2 on POM was investigated in this paper. The structure of the toughened system was characterized using DSC and SEM. When 20 % TPU was incorporated into POM alone, the notched impact strength was 89 % higher than that of neat POM, but the tensile strength and flexural modulus were lowered by 18 % and 40 %, respectively; When 2 % SiO2 was added to POM, the increase in notched impact strength was only 22 %. When 20 % TPU and 2 % SiO2 were incorporated into POM, the notched impact strength was 230 % higher than that of POM, and the tensile strength and flexural modulus were 8 % and 13 % lower, respectively.