检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
出 处:《中国科技论文在线》2010年第9期688-691,共4页
基 金:国家自然科学基金资助项目(20874055);国家高技术研究发展计划(863计划)资助项目(2009AA062903)
摘 要:利用羟基和异氰酸酯基的反应,以聚乙二醇(PEG)为柔性链段,合成了一系列三官能度,具有四重氢键基元(Upy)的聚氨酯(PU)。由于Upy基元自识别形成的四重氢键作用,PU分子间可形成交联网络结构,其热性能和力学性能都随着Upy含量增加而提高,并且其熔融流变行为明显表现出温度和频率依赖性。基于高温下四重氢键基元的破坏,对这种流变学行为进行了解释。A series of polyurethanes with quadruple hydrogen bonding recognizing units (Upy units) at both the ends and the middle of the chain was synthesized based on the reaction between hydroxyl group and isocyanate group using polyethyleneg glycol as the soft chain.The polymers formed interlinked network structures due to the formation of quadruple hydrogen bonding and displayed higher glass transition temperature and better mechanical properties with higher content of Upy units.The rheological performance of the polymers indicated that the complex viscosity was depended on both temperature and frequency.Such rheological performance was explained based on the disruption of quadruple hydrogen bonds at high temperature.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.28