高压下无规聚甲基丙烯酸甲酯的玻璃化转变  

Glass Transition of Atactic Poly(methylmethacrylate) under High Pressure

作　　者：唐兵[1] 吴大诚[1] 李晓毅[2] 赵得禄[2] 赵军[2] 范庆荣[2] 孙昭燕 安立佳 

机构地区：[1]四川大学纺研所,四川成都610065 [2]中科院化学所,北京100080 [3]长春应用化学研究所,吉林长春130022

出　　处：《塑料工业》2003年第7期34-36,共3页China Plastics Industry

基　　金：国家自然科学基金 (基金号 2 99740 19);高等学校博士点专项科研基金(基金号 2 0 0 10 610 0 2 4)资助项目

摘　　要：采用PVT -10 0分析仪测试了无规聚甲基丙烯酸甲酯 (a -PMMA)在 3 0～ 180℃ ,2 0～ 180MPa下的压力 -体积 -温度 (PVT)曲线。与常压下玻璃化转变是某一点不同 ,高压下a -PMMA的玻璃化出现一个反常的转变区 ,并且随着压力增加 ,该转变区逐渐加宽。PVT实验后 ,a -PMMA的数均和重均摩尔质量均明显下降 ;由DSC测试的Tg和TGA测定的Td 也明显降低 。The pressure volume temperature (PVT) data of high molecular weight atactic poly(methylmethacrylate) (a PMMA) were measured by means of PVT 100 analyzer in the pressure range of 20～180 MPa and temperature range of 30～180℃ In the range of high pressure there was an abnormal region of glass transition for a PMMA between the glassy state and rubbery state instead of a single transition point under the normal pressure This glass transition region of the high molecular weight a PMMA became wider with the increase of the pressures It was shown that the molecular weight of the specimen of a PMMA decreased obviously after the PVT measurement The lower values of the glass temperature T g obtained by DSC and the decomposition temperature T d obtained by TGA were found for the specimen after the PVT measurement, which showed the complex thermal history and the pressure ageing of the specimen during the period of the PVT measurement had important effects on the structuresof the sample

关 键 词：高压 无规聚甲基丙烯酸甲酯 玻璃化 a-PMMA PVT测定 GPC DSC TGA 

分 类 号：TQ325.7[化学工程—合成树脂塑料工业]