由大分子PMMA-DPE引发制备Poly(St-alt-MAn)微球

Preparation of poly (styrene-alt-maleic anhydride) microspheres initiated by the poly(methyl methacrylate) oligomer containing 1,1-diphenylethene units

在1,1-二苯基乙烯(DPE)存在下,以甲基丙烯酸甲酯(MMA)为初始单体,偶氮二异丁腈(AIBN)为引发剂,采用本体聚合法制备出含有DPE片段的大分子引发剂PMMA-DPE;然后以PMMA-DPE为引发剂,以苯乙烯(St)和马来酸酐(MAn)为共聚单体,乙酸异戊酯为溶剂,采用自稳定沉淀聚合法制备了单分散的聚(苯乙烯-马来酸酐)(Poly(St-alt-MAn))的微球。研究了PMMA-DPE的用量对聚合物微球的形态、粒径大小及分布的影响。采用FT-IR,UV-V is,1H-NMR和GPC对产物的结构进行了表征,并用SEM观察了聚合物微球的形貌。结果表明,PMMA-DPE能够引发St和MAn的共聚合,随着PMMA-DPE用量的增加,聚合反应的转化率呈增大趋势,聚合物微球的粒径呈下降趋势,而粒径分布系数略有增大。

Poly（ methyl methacrylate） （PMMA） oligomers containing 1,1-diphenylethene （DPE） structural units （PMMA-DPE） have been prepared by the bulk polymerization of methyl methaerylate （MMA） in the presence of DPE with azodiisobutyronitrile （AIBN） as initiator. Narrow-disperse poly （ styrene-alt-maleie anhydride） [ poly （St-air-MAn） ] microspheres were subsequently obtained by metastable precipitation polymerization of styrene （St） and maleic anhydride （MAn） initiated by the PMMA-DPE, with isoamyl acetate as solvent. The structure of the copolymer was confirmed by FT-IR,UV-Vis and 1H-NMR spectroscopy and GPC. The morphology and size of the mierospheres were observed by SEM. The effects of varying the amount of PMMA-DPE on the morphology, particle size and size distribution of the microspheres were investigated. When the mass percentage of PMMA-DPE （based on total monomer amount） increased, the conversion increased and the diameter of the mierospheres decreased, but the distribution of diameter increased slightly.