• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>RSC Advances >Poly(ε-caprolactone)-based shape memory polymers crosslinked by polyhedral oligomeric silsesquioxane
【24h】

Poly(ε-caprolactone)-based shape memory polymers crosslinked by polyhedral oligomeric silsesquioxane

机译：聚（ε-己内酯）的形状记忆聚合物，由多面体低聚SilseseSquioxane交联

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

A series of biodegradable SMP networks with various PCL arm lengths and well-defined star-branched molecular structures were fabricated using polyhedral oligomeric silsesquioxane (POSS) as the core reacting with different molecular weight PCL. Fourier transform infrared spectroscopy (FTIR) was used to follow the reaction, and the cross-link density of the samples was evaluated by the gel content. Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) results showed a similar trend: transition temperature can be tailored by varying the PCL molecular weight; melting temperature of the networks gradually increased with increasing of the PCL molecular weight. The crystallization behavior was studied by DSC and the crystallization temperatures of these networks were influenced by PCL arm lengths. Mechanical properties of the POSS–PCL networks at two different temperatures were compared: tensile strength reaching 12 MPa at room temperature while this figure reduced to around 0.1 MPa above its transition temperature. Outstanding shape memory behaviors of the samples were observed in the strain-controlled cyclic thermomechanical tensile test. The results revealed that sample POSS-N2000 (higher POSS moiety) displayed the most remarkable shape fixity (97%) and recovery ratio (99%), which was induced by lowering the cross-linking density and increasing chain mobility. Finally, the possible molecular mechanism of shape memory was illustrated schematically.
机译：使用多面体低聚Silsesquioxane（POSS）制造具有各种PCL臂长度和明确定义的星分子结构的可生物降解的SMP网络，作为与不同分子量PCL的核心反应。使用傅里叶变换红外光谱（FTIR）遵循反应，并通过凝胶含量评价样品的交联密度。差分扫描量热法（DSC）和动态机械分析（DMA）结果显示出类似的趋势：通过改变PCL分子量可以根据过渡温度来定制;随着PCL分子量的增加，网络的熔化温度逐渐增加。通过DSC研究了结晶行为，并且这些网络的结晶温度受到PCL臂长度的影响。比较两个不同温度的POSS-PCL网络的机械性能：在室温下达到12MPa的拉伸强度，而该数字降低至其转变温度的约0.1MPa。在应变控制的循环热机械拉伸试验中观察到样品的出色形状记忆行为。结果表明，通过降低交联密度和增加的链迁移率，样品POSS-N2000（较高的POSS部分）显示最显着的形状固定度（97％）和回收率（99％），其诱导。最后，示意性地示出了形状记忆的可能分子机制。

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