二氧五环加料方式对共聚甲醛结构及性能的影响

EFFECT OF CHARGING ORDER OF DIOXOLANE ON THE MICROSTRUCTURE AND PROPERTIES OF POLYACETAL

用ＤＳＣ、裂解气相色谱及偏光显微镜研究了聚合时的加料方式，对以二氧五环为共单体的共聚甲醛的结构的影响，并研究了它与热碱稳定性、缺口冲击强度等性能的关系。结果表明，通过特殊加料方式（Ｂ）所得共聚甲醛的热碱稳定性及缺口冲击强度分别比普通加料方式（Ａ）的高出３．６％及０．７１ｋｇｃｍ／ｃｍ２，且前一种共聚甲醛所形成的球晶明显小于后者，说明Ｂ为一种较好的聚合加料方式。

The effect of charging order of dioxolane comonomer in copolymerization with trioxane on microstructure of polyacetal (POM) was investigated by DSC, pyrolysis gas chromatography and polarized microscope. The relationship between the charging order and heat stability or charpy impact strength was stuided, too. The results show that the heat stability and charpy impact strength of POM obtained using a special charging order (B) are 3.6% and 0.71 kg·cm/cm 2 higher than those of general charging order (A), the size of spherulities in POM using the former order is obviously smaller than that of the latter, these indicate that the former order is a better charging order of comonomer during the copolymerization.