利用DMTA和自制热导测试仪测试了4种自制芳香族聚酰亚胺泡沫的玻璃化转变温度(Tg )、静态温度下的热导率(λ)和动态温度作用下的隔热性能;分析了一定厚度的聚酰亚胺泡沫的密度和温度影响热导率的规律;考察了聚酰亚胺泡沫在动态温度下的隔热性能.结果表明:单体(尤其是二胺)刚性越大,聚酰亚胺泡沫的玻璃化转变温度越高;在密度为50～140kg/m3范围内,聚酰亚胺泡沫的密度对热导率的影响较小;在温度为50～350℃范围内,温度的升高使聚酰亚胺泡沫的热导率增加;在动态温度下,聚酰亚胺泡沫表现出明显的热滞后性.%Experimental studies were undertaken to investigate glass transition temperature,thermal conductivity at static temperature and performance of thermal insulation at dynamic temperature of 4 kinds for aromatic polyimide foams by DMTA and self-made apparatus. The relationship of density,temperature between thermal conductivity of polyimide foams and performance of thermal insulation of polyimide foams at dynamic temperature were examined. The results show that stiffness of monomer (especially diamine) has influence on glass transition temperature of polyimide foams; the density of polyimide foams ranging from 50-140kg/m3 has little influence on thermal conductivity; with static temperature ranging from 50-350℃ rising, thermal conductivity of polyimide foams are also rising; at dynamic temperature, polyimide foams show hysteretic nature obviously.
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