以醋酸乙烯酯(VAc)和叔碳酸乙烯酯(VeoVa10)为原料,酒石酸和双氧水为引发剂,在73℃下,通过乳液聚合法制备一系列VeoVa10/VAc乳液,研究了新型乳化剂乙氧基化烷基醇醚磺基琥珀酸酯二钠盐(DNS-330)的用量对乳液性能的影响,同时探讨了乳化剂DNS.330阴离子和非离子双重稳定基团对乳液的稳定机理.研究结果表明,用占单体总质量2.0wt%的DNS.330制备的VeoVa10/VAc乳液的表观粘度为4.724Pa.s、乳胶粒的D50为580nm、粒径分布较窄且稳定性良好.由于DNS.330的阴离子与非离子双重基团稳定的影响,乳胶粒子表面的界面强度增强,乳胶粒子间的斥力增加,故用其制备的VeoVa10/VAc乳液具有较好的流动性和较高的稳定性.
A series of emulsions were prepared at 73 ℃ by emulsion polymerization with versatic acid 10 esters( VeoVa10 )and vinyl acetate (VAc), using ascorhic acid and hydrogen peroxide as initiator, mixture of sodium dodecyl sulfate (SDS) and nonylphenol polyoxyethylene ( OP-10 ) or the ethoxylated alkyl alcohol ether disodium sulfosuccinate(DNS-330) as emulsifier, and PVA as protective colloid. The effects of anionic - nonionic emulsifier (DNS-330) on the emulsion stability, apparent viscosity, and particle size distribution was investigated. Meanwhile, the different effects of DNS-330 and traditional mixed emulsifier SDS/OP-10 on emulsion properties were compared . The results indicated that VeoVal0/VAc emulsion containing DNS-330 (2. Owt% of total monomer)as emulsifier had viscosity. The Ca^2+ ionic, mechanical and narrow particle size distribution and low apparent storage stability of the emulsion were improved. During the stabilization of the emulsion, because of the influence of double-stability group on DNS-330, the particle was stabilized by the non-ionic group with the steric stabilization mechanism and the outside of the particle was stabilized by the anionic group, which provided repulsive force to the latex particles between two similarly charged electric double layers. Moreover, the emulsion stability was improved greatly due to the synergetic effects caused by from the electrostatic and steric stabilization mechanisms.