利用硅烷偶联剂KH570改性的蒙脱石固体颗粒乳化制备稳定的皮克林乳液型烯基琥珀酸酐(ASA)造纸施胶剂,研究了pH值、油水比和固体颗粒浓度对ASA皮克林乳液稳定性及施胶性能的影响.结果表明:改性蒙脱石明显改善了ASA乳液的稳定性;随着pH值的增大,所制备的ASA乳液的稳定性先升高后降低,pH值为7.0时乳液稳定性最高;油水比达3:1时会发生转相,ASA皮克林乳液由水包油(O/W)型乳液转变为油包水(W/0)型乳液;固体颗粒浓度与油水界面处的固体颗粒膜以及连续相中固体颗粒网络结构的形成密切相关;固体颗粒浓度越大,乳液粒径越小,乳液稳定性越好;所制备的ASA乳液的最佳固体颗粒浓度为1.5%~2.0%;改性蒙脱石有效提高了ASA乳液的水解稳定性,具有良好的施胶应用效果.
Stable ASA Pickering emulsions were prepared by using montmorillonite clay-partic|es modified by silane coupling agent KH570 as the particulate emulsifier of ASA and water, and the effects of pI-I value, oil-to-water ratio and particle concentration on the stability and sizing performance of the emulsions were investigated. The resuhs indicate that the presence of modified montmorillonite remarkably improves the stability of ASA emulsions, that the stability first increases and then decreases with the increase in pH value and reaches the maximum at pH 7.0, that a phase inversion from an oil-in-water (O/W) emulsion to a water-in-oil (W/O) emulsion may occur at a oil-to- water ratio of 3:1, that the particle concentration is tightly related to the formations of the particle film at oil-water interface and the clay particle network in water, that higher particle concentration results in smaller droplet size and higher stability of ASA emulsions, that the optimal particle concentration for ASA emulsions ranges from 1.5% to 2.0%, and that both the stability to hydrolysis and the sizing performance of ASA emulsions greatly improve due to the employment of modified montmorillonite.