摘要
通过双螺杆挤出机将硬脂酸钙、硬脂酸镁、硬脂酸锌、氧化镁、氧化锌和甲酸吸收剂H分别加入到聚甲醛(POM)中,研究了这6种甲酸吸收剂对POM黄色指数、热失重5%的时间、表面甲醛与不稳定端基含量和力学性能的影响。结果表明,选用的6种甲酸吸收剂中只有甲酸吸收剂H和氧化锌对POM的白度没有影响;甲酸吸收剂H、氧化锌和硬脂酸镁均可有效提高POM的热稳定性能,其中甲酸吸收剂H的吸收甲醛效果最好,其可通过吸收大量甲醛避免其转化为甲酸来中断POM的酸解反应,从而使添加质量分数为0.1%的甲酸吸收剂H的POM热稳定性能最好,其热失重5%的时间由未添加甲酸吸收剂的39.1 min提高到45.2 min,表面甲醛质量分数和不稳定端基含量分别从1.446%和1870μg/g降低到1.021%和1280μg/g,且力学性能保持不变。
Calcium stearate, magnesium stearate, zinc stearate, MgO, ZnO and formic acid absorber H were respectively added into POM in twin-screw extruder. Influences of these six kinds of formic acid absorbers on yellow index, required-time of thermal losing 5% weight, surface formaldehyde content, unstable end group content and mechanical properties of POM were investigated. The results show that within the six kinds of formic acid absorbers, only formic acid absorber H and ZnO have no effect on the whiteness of POM. Formic acid absorber H, ZnO and magnesium stearate can remarkably improve thermal stability of POM, especially formic acid absorber H, it can absorb mass formaldehyde to avoid generating formic acid for interrupting acidolysis of POM. Comparing with POM which has no formic acid absorber, the required time of thermal losing 5% weight of POM with 0. 1% formic acid absorber H increases from 39.1 min to 45.2 min, the surface formaldehyde and unstable end group content respectively decreases from 1 A46% and 1870 μg/g to 1.021% and 1280 μg/g, and the mechanical properties remain unchanged.
出处
《工程塑料应用》
CAS
CSCD
北大核心
2014年第7期100-103,共4页
Engineering Plastics Application
