搜索:  
Homopolymer and Random Copolymer of Polyhedral Oligomeric Silsesquioxane (POSS)-Based Side-Chain Polynorbornenes: Flexible Spacer Effect and Composition Dependence  
Homopolymer and Random Copolymer of Polyhedral Oligomeric Silsesquioxane (POSS)-Based Side-Chain Polynorbornenes: Flexible Spacer Effect and Composition Dependence
资料类型: PDF文件
关键词: POSS  
资料大小: 544k
所属学科: 高分子物理
来源: 来源网络
简介:
A series of homopolymers and random copolymers of polyhedral oligomeric silsesquioxane (POSS)-based side-chain polynorbornenes were prepared using ring-opening metathesis polymerization. For the homopolymer P-z-POSS (z represents the spacer length, z = 5, 12, 17), the POSS groups tethered to the side-chain are linked to the polynorbornene backbone through the flexible spacer with different lengths. For the random copolymer P-6-co-17(X/Y) (X/Y = 1/1, 3/1, 6/1, 9/1), the composition was regulated by adjusting the molar feed ratio X/Y of the norbornene monomer with butyl ester side group (M-6) to the POSS containing monomer with the longest spacer (M-17-POSS). Using various techniques, we studied the spacer length effect on POSS crystallization of the homopolymers and the composition dependence of physical properties of the copolymers. It is found that P-5-POSS is amorphous. On the contrary, POSS crystallization is observed in P-12-POSS and P-17-POSS, and the longer the spacer is, the higher the POSS crystallization ability is. With the co-monomer of M-17-POSS, all the P-6-co-17(X/Y) samples can have the POSS group to crystallize, resulting in a nano-segregation similar to the lamellar morphology. The lamellar period is inversely proportional to the POSS volume fraction. The POSS crystallites are raft-like, containing two layers of POSS groups stacked together. Uniaxial stretching can well align the POSS crystallites in the copolymers to be parallel to the stretching direction, and the lamellar period is decreased with increasing the strain. Varying X/Y from 1/1 to 9/1 changes the copolymer from plastic to thermoplastic elastomer, wherein the later takes the POSS crystallites as the physical cross-links.
上传人: renxiangkui
上传时间: 2018-08-19 8:20:27
下载次数: 0
消耗积分: 0  
立即下载:
1人
1人
1人
友情提示:下载后对该资源进行评论,即可奖励2分。
报告错误:  1.下载无效  2. 资料明显无价值  3. 资料重复存在

相关评论 共有0人发表评论 更多评论
你还没有登录,无法发表评论,请首先 登录 注册
免责声明:本站部分资源由网友推荐,来自互联网,版权属于原版权人,如果不慎侵犯到您的权利,敬请告知,我们会在第一时间撤除。本站中各网友的评论只代表其个人观点,不代表本站同意其观点。