摘要
采用微波研究了苯酚封端的聚氨酯预聚物 (PU )与3,3' -二氯 -4,4' -二氨基 -二苯基甲烷(MOCA)的固化过程中的热行为 ,测定了固化过程中的温度变化及温度变化速率 ,初步探讨了固化过程中温度变化以及温度变化速率与体系固化过程之间的关系 ,并与热固化过程进行了比较。研究结果发现 :微波固化能显著提高PU/MOCA体系固化速率 ,在微波场中 ,体系的温度变化和温度变化速率不仅依赖于微波功率 ,而且与体系的结构密切相关 ,而热固化的温度变化和温度变化速率均较小 。
In this paper,thermal behavior of the crosslinking of phenol-blocked polyurethane(PU)with3,3-dichloro-4,4-diaminodiphenylmethane(MOCA)by pulsed microwave field and convenˉtional heating were investigated in detail.A complete analysis of the various stages of the curing mechanism was made through the variation of the temperature of the sample under the microwave irradiation.The dependence of variations of the temperature and the cure rate on the microwave power was also examined.Results revealed microwave could accelerate the curing rate obviously and curing rate for the system relies on microwave power and the structure of the sample,which associated dielectric loss.Compared to microwave curing,variation of temperature and curing rate for the thermal curing system at120℃are lower,and have little relationship with the structure.
出处
《绝缘材料》
CAS
北大核心
2004年第6期32-35,共4页
Insulating Materials
关键词
聚氨酯
微波固化
热行为
phenol blocked polyurethane
microwave curing
thermal behavior
