摘要
提出一种新的概念——偶极子去极化程度和计算式来量化研究聚甲基丙烯酸甲酯(PMMA)在加速热氧老化过程中其相对电容率急剧下降这一现象。通过介质损耗测试仪和阿贝折射仪考察后固化工艺和添加剂(链转移剂、内增塑剂、交联剂)对试样的偶极子去极化程度的影响。研究发现:链转移剂和测试频率对偶极子去极化程度基本没有影响,后固化工艺能减小试样的偶极子去极化程度,内增塑剂和交联剂都能增大试样的偶极子去极化程度。在所研究的工艺与配方中,交联剂质量份数为6%的试样的偶极子去极化程度达到75%。
A novel concept called "degree of dipole posed to deal with the sharp reduction of relative depolarization" and its calculational formula were propermittivity of PMMA during accelerated thermally aging. A loss meter and a refractometer were employed to test the various effects on the depolarization. It was showed that post-curing may increase, plasticization and cross-linking may decrease the depolarization, while transfer agent and testing frequency had no effect. A sample with 6 % of cross-linking agent had a degree of dipole depolarization of 75 %.
出处
《中国塑料》
CAS
CSCD
北大核心
2006年第4期62-64,共3页
China Plastics
关键词
聚甲基丙烯酸甲酯
偶极子去极化程度
相对电容率
poly(methyl methacrylate)
degree of dipole depolarization
relative capacitance ratio