PVAc-AN/PS乳胶膜可观测“网点”的构建及形状记忆效应研究  

Construction ofobservable“net-point”and research on the shape memory effect of PVAc-AN/PS latex film

作　　者：陈俞程 陈培健 孙嘉星 李志国[1] CHEN Yucheng;CHEN Peijian;SUN Jiaxing;LI Zhiguo(College of Material Science and Engineering, Northeast Forestry University, Harbin 150040, China)

机构地区：[1]东北林业大学材料科学与工程学院,哈尔滨150040

出　　处：《功能材料》2021年第3期3206-3213,共8页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(31570557);黑龙江省自然科学基金资助项目(C2018008);黑龙江省博士后科研启动基金资助项目(LBH-Q14004)。

摘　　要：研究通过在聚乙酸乙烯酯(PVAc)乳胶粒表面构建形貌可控的聚苯乙烯(PS)壳层“突起”结构,并以其作为PVAc形状记忆效应中的可观测“网点”,实现了大形变量、高恢复率PVAc基形状记忆聚合物的制备。通过采用丙烯腈(AN)为接枝单体,制备了以PVAc为核、PS为壳的PVAc基核/壳结构乳胶粒(PVAc-AN/PS),首次实现了规整形貌乳胶粒表面可观测“网点”的构建与调控。通过扫描电子显微镜与透射电子显微镜表征了PVAc-AN/PS乳胶粒的形貌,并考察了乳胶粒形貌随壳层St添加量的变化而发生的衍化过程。采用单轴拉伸形状记忆循环实验研究了PVAc-AN/PS乳胶膜的形状记忆效应,并通过调控壳层St的添加量有效改善了PVAc-AN/PS乳胶膜的形状恢复率。实验结果表明,PVAc-AN/PS核/壳乳胶膜形变尺寸高达1500%以上,同时形状恢复率可达85%以上,这为拓宽形状记忆聚合物中“网点”的设计范畴及调控形状记忆性能提供了新途径。PVAc latex-based shape memory polymers(SMP)with high strain and recovery ratio are fabricated by formation of poly(vinyl acetate)(PVAc)core and polystyrene(PS)shell through acrylonitrile grafting(PVAc-AN/PS)in emulsion polymerization.It is exhibited that the morphology-controllable“protuberances”on the latex core could be acted as observable“net-point”during the shape memory cycle.The morphology of PVAc-AN/PS particles with core-shell structure is characterized by scanning electron microscope and transmission electron microscope,and the morphological evolution of the PVAc-AN/PS latex particles varying with the quantity of PS is investigated.The shape memory performance of PVAC-AN/PS latex film is explored by uniaxial stretch shape memory cycle experiment,demonstrating that the shape recovery ratio of the PVAc-AN/PS latex film is effectively improved by adjusting the amount of St added during the polymerization.The experimental results show that PVAc-AN/PS core-shell latex film possesses high strain more than 1500%with shape recovery ratio of 85%or more.Therefore,this study provides a new approach for designing“net-point”in shape memory effect of polymers and regulating the shape memory performance of polymers.

关 键 词：形状记忆 核/壳乳胶粒 网点 相分离 大形变量 

分 类 号：TB34[一般工业技术—材料科学与工程] TB381