自组装核壳纳米微域交联的聚丙烯酸酯基聚合物的制备、性能及形状记忆机理  

Preparation,Properties and Shape Memory Mechanism of Polyacrylate-based Polymer Crosslinked by Self-assembled Core-shell Nano-microdomain

作　　者：李明菲 吕佳宁 李兴建 丁小斌[2] LI Mingfei;LYU Jianing;LI Xingjian;DING Xiaobin(College of Materials Science and Engineering,Linyi University,Linyi 276000,China;Chengdu Institute of Organic Chemistry,Chinese Academy of Sciences,Chengdu 610041,China)

机构地区：[1]临沂大学材料科学与工程学院,临沂276000 [2]中国科学院成都有机化学研究所,成都610041

出　　处：《高等学校化学学报》2023年第11期189-198,共10页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:22275076);山东省自然科学基金(批准号:ZR2020QE092);2023国家级大学生创新创业训练计划项目资助。

摘　　要：以双键封端的活性Pluronic F127三嵌段共聚物自组装形成的活性核壳纳米胶束作为多功能纳米交联剂,丙烯酸羟乙酯和丙烯酸为共单体,通过紫外光引发交联剂和单体的自由基聚合,制备了自组装核壳纳米微域交联的聚丙烯酸酯基形状记忆聚合物.利用差示扫描量热仪、动态热机械分析仪和万能拉力试验机对聚丙烯酸酯基形状记忆聚合物的热性能、动态热机械性能和力学性能进行了表征.结果表明,随着丙烯酸酯单体浓度的降低,其玻璃化转变温度、室温模量、玻璃态模量与橡胶态模量的比值、拉伸强度和断裂伸长率都逐渐降低,表现出兼具高强度和高韧性的特点.对聚丙烯酸酯基形状记忆聚合物的形状固定率、回复率和回复速率进行了定量表征.结果表明,当单体浓度超过1.97 mol/L时,聚丙烯酸酯基形状记忆聚合物展现出优异的形状记忆性能,形状固定率超过97%,回复率超过98%,回复速率超过8.8%/min.最后,通过应力松弛对该形状记忆聚合物体系的形状记忆机理进行了分析.The polyacrylate-based shape memory polymer(SMP)with self-assembled core-shell nano-microdomains was prepared by UV-initiated free-radical polymerization of the active core-shell nanomicelles formed by self-assem-bly of active Pluronic F127 triblock copolymer end-capping acrylate groups as multifunctional nano-crosslinker and hydroxyethyl acrylate and acrylic acid as co-monomers.The thermal properties,dynamic thermo-mechanical proper-ties and mechanical properties of the polyacrylate-based SMPs were characterized by differential scanning calorime-ter,dynamic thermo-mechanical analyzer and universal tensile testing machine.The results showed that the glass transition temperature,room temperature modulus,modulus ratio of upper and lower glass transition,tensile strength and elongation at break of the SMPs decreased gradually with the decreasing concentration of acrylate mono-mer.The SMP system exhibited both high strength and high toughness.The shape fixity ratio(Rf),shape recovery ratio(Rr),and shape recovery rate(Vr)of the SMPs were quantitatively characterized.The results showed that when the monomer concentration exceeded 1.97 mol/L,the SMP exhibited excellent shape memory performance,with Rf of more than 97%,Rr of above 98%and Vr of over 8.8%/min.Finally,the shape memory mechanism of the SMP system was analyzed by stress relaxation.

关 键 词：形状记忆聚合物 聚丙烯酸酯 核壳纳米微域 形状记忆效应 

分 类 号：O631[理学—高分子化学]