脱模溶剂对制备聚苯乙烯表面大孔材料的影响

采用马来酸酐-醋酸乙烯共聚物乳液为模板,分别以水、乙醇和丙酮为脱模溶剂,合成了表面层(厚度为10μm)为大孔结构(孔径为250～400nm)的聚苯乙烯(PS)孔材料.用扫描电子显微镜(SEM)测定了材料表面的微观形貌,SEM照片显示出3种脱模溶剂均能制备PS大孔材料,其中水为脱模溶剂时对PS基材的不利影响最小.用傅立叶红外光谱仪(FTIR)表征了脱模后孔内被固定的特征基团,结果表明,不同的脱模溶剂分别对应不同的孔内基团,即水-羧基、乙醇-酯基及丙酮-酐基.测定了3种脱模溶剂的脱模速率,其顺序为丙酮>>乙醇>水.

EFFECT OF SOLVENTS ON PREPARING SURFACE-MACROPOROUS POLYSTYRENE

Surface-macroporous polystyrene with sub-micrometer(250～400 nm)pores and a surface thickness of 10 μm has been synthesized using a maleic anhydride-alt-vinyl acetate copolymer microspheres as template,followed by removal of the template with water,ethanol or acetone.The surface features of the samples were investigated by scanning electron microscopy(SEM).The SEM micrographs indicate that macroporous PS can be prepared in each case,with use of water as the template's solvent having the smallest adverse effect on the polymer.The functional groups present on the surface of pores after the template was dissolved are different in each case and have been identified by FTIR,dissolution of template in water gives rise to carboxyl groups,dissolution of template in ethanol gives rise to ester groups whilst dissolution of template in acetone gives acid anhydride groups.The rate of template dissolving is fastest in acetone and slowest in water.