语音播报
应固体润滑国家重点实验室邀请,美国田纳西大学教授Bin Zhao来中国科学院兰州化学物理研究所交流访问,学术报告如下:
报告题目:Functional and Responsive Macromolecular Brush Materials
报 告 人:Bin Zhao, Professor, Department of Chemistry, University of Tennessee Knoxville
报告时间:6月9日(星期五) 下午15:00
报告地点:兰州化物所理化楼三楼多功能厅
报告摘要:
Linear polymer chains densely tethered by one end to a solid substrate or a polymer backbone are intriguing polymer systems, with the former being commonly called polymer brushes and the latter being descriptively termed molecular bottlebrushes. In all these systems, the grafted polymer chains are highly stretched, exhibiting unique structures and properties. In this talk, I will present two types of macromolecular brush materials: oil-soluble polymer brush-grafted nanoparticles (hairy NPs) as engine lubricant additives and stimuli-responsive shape-changing binary molecular bottlebrushes. While NPs have been viewed as potentially effective additives for lubricants for friction and wear reduction, further development is hindered by their dispersability and long-term stability in oils. By growing oil-soluble polymer brushes from NPs viasurface-initiated polymerization, we have shown that such hairy NPs exhibit excellent dispersability and superior stability in polyalphaolefin (PAO), the base oil for engine lubricants. With addition of 1 wt% hairy NPs into PAO, significant reductions in friction coefficient (up to ~ 40%) and wear volume (up to ~ 90%) are achieved. In the second part of the talk, I will present our recent work on stimuli-responsive molecular bottlebrushes. A “grafting to” method via “click” reaction has been developed to synthesize molecular brushes; the modular nature and the high grafting efficiency of this method allow for synthesis of heterografted molecular brushes with two or more distinct side chain polymers and facile tuning of the molar ratio of different side chain polymers. We show that thermosensitive binary heterografted molecular brushes undergo shape changing between worm-like and collapsed yet stable globular conformations upon temperature changes, which is utilized to control interactions between brushes and environment.
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© 1996 - 中国科学院 版权所有 京ICP备05002857号-1 京公网安备110402500047号 网站标识码bm48000002
地址:北京市西城区三里河路52号 邮编:100864
电话: 86 10 68597114(总机) 86 10 68597289(总值班室)
编辑部邮箱:casweb@cashq.ac.cn
© 1996 - 中国科学院 版权所有
京ICP备05002857号-1
京公网安备110402500047号
网站标识码bm48000002
地址:北京市西城区三里河路52号 邮编:100864
电话:86 10 68597114(总机)
86 10 68597289(总值班室)
编辑部邮箱:casweb@cashq.ac.cn