【摘要】 采用无皂乳液聚合法,将低取代度阳离子淀粉(CS-8)和苯乙烯(St)、丙烯酸正丁酯(BA)、甲基丙烯酸二甲基氨基乙酯(DMAEMA)单体进行接枝共聚反应,制备淀粉基苯乙烯丙烯酸丁酯乳液,研究了聚合反应条件对乳液性能的影响,并对合成的乳液进行表征和应用效果研究.以乳液凝胶率、粒径、Zeta电位、Cobb值及胶乳性状为指标优化得到最佳聚合条件为:软硬单体比m(St)∶m(BA)为1.5∶1.0,阳离子淀粉与单体比m(CS-8)∶m(单体)为1∶2,功能单体DMAEMA用量为单体总量的1%,乳液理论固含量为30%.此条件下合成的乳液稳定性及施胶性能指标较好.红外光谱分析表明苯乙烯和丙烯酸丁酯均参与了阳离子淀粉的接枝聚合反应.热重分析表明聚合反应生成的为无规共聚物.将淀粉基苯乙烯丙烯酸丁酯乳液应用于瓦楞原纸表面施胶,Cobb值可达到36.6 g/m2,比玉米淀粉施胶降低了68.7%;初始接触角为113.8°,抗水性能好;横向环压指数增加了44.0%,纵向裂断长增加71.9%,纵向耐折次数增加171.4%,增强效果显著.SEM分析表明淀粉基苯乙烯丙烯酸丁酯乳液可在纤维表面形成致密施胶层.更多还原

【Abstract】 Soap-free emulsion polymerization method was used to graft low substitution cationic starch(CS-8)onto styrene(St),n-butyl acrylate(BA),and dimethylaminoethyl methacrylate(DMAEMA)monomers to prepare starch-based styrene butyl acrylate emulsion. The influence of polymerization conditions on the performance of the emulsion was analyzed.The synthesized emulsion was characterized and its application was studied. Optimized polymerization conditions using emulsion gel fraction,particle size,Zeta potential,Cobb value,and latex properties as indicators are as follows:the ratio of soft and hard monomers m(St)∶m(BA)is 1.5∶1.0,the ratio of starch to monomers m(CS-8)∶m(monomer)is 1∶2,the amount of functional monomer DMAEMA is 1% of the total monomer,and the theoretical solid content of the emulsion is 30%. Under these conditions,the stability and sizing performance of the synthesized emulsion are good. FT-IR analysis showed that both styrene and butyl acrylate participated in the grafting copolymerization of starch. Thermogravimetric analysis showed that the polymerization produced random copolymers. Applying starch-based styrene butyl acrylate emulsion to the surface sizing of corrugated base paper,the Cobb value can reach 36.6 g/m2,which is 68.7% lower than that of corn starch sizing;the initial contact angle is 113.8°,which means it has better water resistance;the pressure index increased by 44.0%,the longitudinal crack length increased by 71.9%,and the number of longitudinal folding resistances increased by 171.4%. SEM analysis showed that starch-based styrene butyl acrylate emulsion could form a dense sizing layer on the fiber surface.更多还原