组装-聚合法制备聚苯乙烯-聚丙烯酸胶束和凝胶

发布时间：2018-07-23 09:53

【摘要】：通过苯乙烯和丙烯酸单体的预组装再聚合的制备方法,在不改变共聚物浓度的前提下制备了共聚物胶束溶液和凝胶,探讨了引发剂(偶氮二异丁腈)浓度对生成的共聚物的聚集体结构以及分子结构的影响.利用核磁共振氢谱、扫描电子显微镜和透射电子显微镜等表征了共聚物的分子结构和聚集行为,此外,借助耗散粒子动力学方法模拟了该体系,辅助实验阐明了不同引发剂浓度下生成的共聚物聚集体结构及相对应的共聚物分子结构,在此基础上,利用动态机械热分析和流变学的表征技术,研究了共聚物胶束溶液和凝胶的流变特性.结果表明,在单体浓度不变的情况下,高引发剂浓度时该体系趋于形成平均嵌段长度较长的两嵌段共聚物,生成稳定的胶束溶液,而低引发剂浓度时趋于形成交替共聚物,得到物理凝胶,耗散粒子动力学模拟得到了与实验一致的结果.流变学表征发现胶束体系和凝胶体系均呈现剪切变稀行为,并确定了凝胶体系的凝胶点及恢复性.
[Abstract]:The copolymers micelle solution and gel were prepared by pre-assembly and repolymerization of styrene and acrylic monomers without changing the concentration of the copolymers. The influence of the concentration of initiator (azodiisobutyronitrile) on the aggregate structure and molecular structure of the copolymers was studied. The molecular structure and aggregation behavior of the copolymers were characterized by NMR, SEM and TEM. In addition, the system was simulated by dissipative particle dynamics. The copolymers' aggregates and corresponding copolymers with different initiator concentrations were elucidated by auxiliary experiments. On this basis, dynamic mechanical thermal analysis and rheological characterization techniques were used to characterize the copolymers. The rheological properties of copolymer micelle solution and gel were studied. The results show that under the condition of constant monomer concentration, the system tends to form diblock copolymers with long average block length at high initiator concentration, resulting in stable micelle solution, while alternating copolymers tend to form at low initiator concentration. The physical gel was obtained, and the simulation results of dissipative particle dynamics were in agreement with the experimental results. It was found that both micellar and gel systems showed shear-thinning behavior, and the gel point and recovery of the gel system were determined.
【作者单位】：华东理工大学材料科学与工程学院上海市先进聚合物材料重点实验室;
【基金】：国家自然科学基金(基金号21304035,21234002,21474029) 教育部科学技术研究重大项目(项目号313020)资助
【分类号】：TQ316.3

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