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【创源大讲堂】Vitrimers: Mechanics and Applications报告通知
作者:杨卓然   日期:2016-12-19     点击数:186  

讲座时间:2016年12月21日(周三)下午 3:0   

讲座地点:九里校区行政楼2楼学术报告厅

主  讲:齐航 教授(佐治亚理工学院,美国)

题  目:Vitrimers: Mechanics and Applications

简  历: 清华大学学士、硕士,麻省理工博士。2004-2014年科罗拉多大学波尔得分校任教,现为佐治亚理工学院教授。研究领域涉及:软物质的非线性力学与多场性能、形状记忆高分子、4D打印等。2007年获美国NSF CAREER award,2015年当选AMSE Fellow(会士)。

内容简介:Vitrimers are a novel group of thermosetting polymers that can be processed like plastics by bond exchange reactions (BER). During the operation, polymer topology could be rearranged in complying the external deformation and release the internal stress, but the network integrity is maintained and the average functionality of polymer chains is unchanged. This kind of reactions enables some interesting properties, such as surface welding, reprocessing and recycling. In this talk, we first experimentally study surface welding in detail. Based on experimental observations, we develop a theoretical model to for the welding of polymers with thermally induced BERs. The developed model is featuring with a concise modeling frame, where the material interfacial behavior is extrapolated from that of bulk material and all the parameters could be easily prescribed by using standard polymer tests. The model predicts experimental observations on the elastic modulus and interfacial fracture energy of welded vitrimers with adequate accuracy, and helps to identify the dependency of surface welding efficiency on the applied thermal and mechanical fields: while the interfacial kinetics characterized by the chain density increment on the real contact area of interface is only dependent on the welding time and temperature, the pressure will affect the real contact area under the consideration of surface roughness of thermoset polymers, and consequently influence their mechanical properties. Finally, we present a few our recent progress, such as pressure-free reprocessing, near 100% recycling of carbon-fiber reinforced vitrimer composites, and 3D printing of vitrimers.

主办:研究生院

承办:力学与工程学院   应用力学与结构安全四川省重点实验室