高分子分散剂对分散聚合制备聚甲基丙烯酸甲酯微球分散效果的影响  

Influence of Polymer Dispersants on Dispersion Effect of Polymethyl Methacrylate Microspheres by Dispersion Polymerization

作　　者：孙春雨 苏海棠 韩雪莲 姜勇[1] 王志飞[1] Chunyu Sun;Haitang Su;Xuelian Han;Yong Jiang;Zhifei Wang(School of Chemistry and Chemical Engineering,Southeast University,Nanjing 210096,China)

机构地区：[1]东南大学化学化工学院,江苏南京210096

出　　处：《高分子材料科学与工程》2023年第7期1-7,共7页Polymer Materials Science & Engineering

基　　金：国家自然科学基金资助项目(81771976);国家重点研发计划(Grant 2018 YFC1901202);病原与生物安全国家重点实验室(军事医学科学院,SKLPBS2134)。

摘　　要：以甲基丙烯酸甲酯为聚合单体、偶氮二异丁腈为引发剂,通过分散聚合方法在甲醇/水介质中制备了1~2μm的聚甲基丙烯酸甲酯(PMMA)微球,研究了4种高分子分散剂对微球粒径和均匀性的影响并探讨了其影响机制。通过傅里叶变换红外光谱仪和扫描电子显微镜对微球的化学组成和形貌进行了表征,结果表明,不同分散剂对微球尺寸及其分布有着显著影响,以聚乙烯醇(PVA)作分散剂时体系容易失稳,产生颗粒沉降,有小颗粒产生,微球平均粒径(Dn)为1.2μm、多分散系数(PDI)为0.045;以聚乙烯吡咯烷酮(PVP)作分散剂微球均一性较差,体系也会产生颗粒聚并沉降,Dn为1.45μm、PDI为0.105;以聚丙烯酸(PAA)作分散剂,得到均一性更差的微球,Dn为1.85μm、PDI为0.3;以聚乙二醇(PEG)为分散剂则能得到均匀的微球,Dn为1.15μm、PDI为0.041,微球粒径和多分散系数随着PEG相对分子质量的增大呈先减小后增大的趋势;粒径随PEG浓度增加呈先增大后减小趋势,在添加量超过20%后,粒径随浓度增加而减小,PDI随PEG浓度的变化趋势与粒径基本一致。With methyl methacrylate as polymerization monomer and 2,2’-azobisisobutyronitrile as initiator,polymethyl methacrylate(PMMA)microspheres with the particle size of 1~2μm were prepared by dispersion polymerization in methanol/water medium.The effects of four macromolecular dispersants on the particle size and monodispersity of PMMA microspheres were examined and their influencing mechanisms were discussed.The chemical composition and morphology of the microspheres were characterized by Fourier-transform infrared(FT-IR)spectroscopy and scanning electron microscopy,the results show that different dispersants have significant effect on the size and distribution of microspheres.When polyvinyl alcohol(PVA)is used as dispersant,the system is easily destabilized,resulting in particle sedimentation and small particles,the average diameter of microsphere(Dn)is 1.2μm,polydispersity index(PDI)is 0.045.The monodispersity of the microspheres with polyvinylpyrrolidone as dispersant is poor,and the system will also produce particle aggregation and sedimentation,Dn is 1.45μm,PDI is 0.105;with polyacrylic acid(PAA)as dispersant,poorer monodispersity is obtained,Dn is 1.85μm,PDI is 0.3;while polyethylene glycol(PEG)is used as dispersant,uniform microspheres are obtained,Dn is 1.15μm,PDI is 0.041.The particle size and polydispersity index of microspheres decrease first and then increase with the increase of PEG molecular weight;the particle size also increases first and then decreases with the increase of PEG concentration,and decreases with the increase of PEG concentration after the addition of more than 20%.The changing trend of PDI with PEG concentration is basically consistent with the particle size.

关 键 词：聚甲基丙烯酸甲酯微球 分散聚合 分散剂 单分散 

分 类 号：O632.51[理学—高分子化学]