Composition dependence of the glass transition of polymer-diluent mixtures: 2. Two concomitant glass transition processes as a general feature of plasticized polymers
Composition dependence of the glass transition of polymer-diluent mixtures: 2. Two concomitant glass transition processes as a general feature of plasticized polymers
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聚合物-稀释剂混合物的玻璃化转变的成分依赖性：2. 两种伴随的玻璃化转变过程作为增塑聚合物的一般特征
DOI：
10.1016/0032-3861(87)90045-0
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发表时间：
1987
期刊：
影响因子：
4.6
通讯作者：
M. Pizzoli
中科院分区：
文献类型：
--
作者：
M. Scandola;G. Ceccorulli;M. Pizzoli
关于聚合物-稀释剂混合物的玻璃化转变温度T g的现有理论和经验处理并不能解释T g组成依赖性中“尖点”的出现或这些作者最近报道的两个相伴的玻璃化转变。由于Braun和Kovacs，预测T g与浓度的曲率变化的唯一治疗方法不能令人满意地描述所研究的七种聚合物-稀释剂系统的行为。为了与现有的文献数据的结果进行比较，开发了一个归一化程序，其主要效果是证据表明，所有的聚合物-稀释剂系统的Tg浓度依赖性是由两个分支。它的结论是，在聚合物-稀释剂的混合物仍然被认为是均匀的在宏观水平上发生两种不同的动员现象，有关动员的“受阻稀释剂”和“塑化聚合物”，分别。单独揭示这两种现象的可能性在很大程度上取决于所使用的技术以及所研究的二元系统的特殊物理性质。
The available theoretical and empirical treatments concerning the glass transition temperature, T g, of polymer-diluent mixtures do not account for the occurrence of the ‘cusp’in the T g composition dependence or of the two concomitant glass transitions recently reported by these authors. The only treatment predicting a change of curvature in T g vs. concentration, due to Braun and Kovacs, does not describe satisfactorily the behaviour of the seven polymer-diluent systems examined. In order to compare the results with the available literature data, a normalization procedure is developed, whose main effect is to evidence that the T g concentration dependence of all polymer-diluent systems is composed of two branches. It is concluded that in polymer-diluent mixtures still considered homogeneous at a macroscopic level two different mobilization phenomena occur, related to mobilization of ‘hindered diluent’and ‘plasticized polymer’, respectively. The possibility of revealing the two phenomena individually depends strongly on the technique being used as well as on the peculiar physical properties of the binary system being examined.