• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Applied Polymer Science >Glass-transition temperatures and rheological behavior of methyl methacrylate-styrene random copolymers
【24h】

Glass-transition temperatures and rheological behavior of methyl methacrylate-styrene random copolymers

机译：甲基丙烯酸甲酯-苯乙烯无规共聚物的玻璃化转变温度和流变行为

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Poly(methyl methacrylate-ran-styrene) copolymers were synthesized under monomer-starved conditions by emulsion copolymerization. The glass-transition temperatures (Tg's) of the copolymers were measured by differential scanning calorimetry (DSC) and torsional braid analysis (TBA). The results showed that the methyl methacrylate-styrene random copolymers produced an asymmetric T-g versus composition curve, which could not even be interpreted by the Johnston equation with different contributions of dyads to the T-g of the copolymer considered. A new sequence distribution equation concerning different contributions of triads was introduced to predict the copolymer's T-g. The new equation fit the experimental data exactly. Also, the T-g determined by TBA (T-gTBA) was higher than the one determined by DSC (T-gDSC) and the difference was not constant. The rheological behavior of the copolymers was also studied. T-gTBA - T-gDSC increased with increasing flow index of the melt of t e copolymer, and the reason was interpreted. (C) 2003 Wiley Periodicals, Inc. [References: 17]
机译：在单体缺乏的条件下，通过乳液共聚合成了聚甲基丙烯酸甲酯-苯乙烯-苯乙烯共聚物。通过差示扫描量热法（DSC）和扭转编织分析（TBA）测量共聚物的玻璃化转变温度（Tg）。结果表明，甲基丙烯酸甲酯-苯乙烯无规共聚物产生不对称的T-g相对于组成曲线，这甚至不能用约翰斯顿方程解释，因为二元组对所考虑的共聚物的T-g贡献不同。引入了有关三单元组不同贡献的新序列分布方程，以预测共聚物的T-g。新方程式完全符合实验数据。另外，由TBA确定的T-g（T-gTBA）高于由DSC确定的T-g（T-gDSC），并且该差不是恒定的。还研究了共聚物的流变行为。 T-gTBA-T-gDSC随着共聚物熔体流动指数的增加而增加，并解释了原因。 （C）2003 Wiley Periodicals，Inc. [参考：17]

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号