Abstract:

Antioxidant 1010 and copolyamides（COPA）were used as large molecules free radical scavenger and formaldehyde absorbents for polyoxymethylene（POM）respectively，to investigate the ultraviolet（UV）aging properties of the blend. The effect of different compositions on mechanical properties and microstructure of POM was studied. Analysis with polarized light microscopy（PLM）and differential scanning calorimetry（DSC）showed crystallizing nucleation effects of antioxidant and COPA on POM. The contents of both antioxidant and COPA of 0.5% gave the best performance of UV aging. Mechanical properties were also excellent. TGA results showed that decomposition temperature of the blend was higher. The blend presented typical non-Newtonian fluid behavior，and when antioxidant contents was less than 0.5%，its complex viscosity was higher than POM. After UV ageing，the complex viscosity of the blend was also higher than POM.

摘要：

选用抗氧剂1010作为大分子自由基的捕捉剂，共聚酰胺（COPA）作为甲醛的吸收剂对聚甲醛（POM）共混体系进行紫外老化性能研究，考察不同组成的复合体系对POM力学性能和微观结构的影响。偏光显微镜（PLM）和差示扫描量热仪（DSC）分析结果表明：少量抗氧剂1010和COPA对POM起到了结晶成核作用，当抗氧剂和COPA含量均为0.5%时，POM耐紫外老化性能较佳。此时，力学性能优异。热重分析结果表明：加入抗氧剂后，POM分解温度有所提高。流变行为研究表明：POM共混体系呈现典型的非牛顿流体行为，当抗氧剂含量小于0.5%时，共混体系复数黏度均高于纯POM；紫外老化后性能亦如此。