文献类型：期刊文献

英文题名：Stabilization of CO2-in-water emulsions with high internal phase volume using PVAc-b-PVP and PVP-b-PVAc-b-PVP as emulsifying agents

作者：Wen, Li[1];Wang, Liwen[1];Fang, Shuyi[1];Bao, Lei[1];Hu, Dongdong[1];Zong, Yuan[1];Zhao, Ling[1];Liu, Tao[1]

机构：[1]East China Univ Sci & Technol, Shanghai Key Lab Multiphase Mat Chem Engn, Shanghai 200237, Peoples R China

年份：2018

卷号：135

期号：23

外文期刊名：JOURNAL OF APPLIED POLYMER SCIENCE

收录：;EI(收录号：20181104912002);WOS:【SCI-EXPANDED(收录号:WOS:000427252800021)】；

基金：The authors are grateful to the National Science Foundation of China (21376087 and 21676081). The authors also thank the anonymous reviewers and editor for their helpful suggestions and enlightening comments.

语种：英文

外文关键词：copolymers; foams; phase behavior

摘要：Two newly-designed hydrocarbon surfactants, that is, poly(vinyl acetate)-block-poly(1-vinyl-2-pyrrolidone) (PVAc-b-PVP) and PVP-b-PVAc-b-PVP, were synthesized using reversible addition-fragmentation chain transfer polymerization and used to form CO2/water (C/W) emulsions with high internal phase volume and good stability against flocculation and coalescence up to 60 h. Their structures were precisely determined by nuclear magnetic resonance, gel permeation chromatography, thermal gravimetric analysis, and differential scanning calorimetry. Besides low temperature and high CO2 pressure, the surfactant structures were the key factors affecting the formation and stability of high internal phase C/W emulsions, including the polymerization degrees of CO2-philic block (PVAc) and hydrophilic block (PVP), as well as the number of hydrophilic tail. The surface tension of the surfactant aqueous solution and the apparent viscosity of the C/W emulsions were also measured to characterize the surfactants efficiency and effectiveness. The surfactants with double hydrophilic tails showed stronger emulsifying ability than those with single hydrophilic tail. The great enhancement of the emulsions stability was due to decrease of the interface tension as well as increase of the steric hindrance in the water lamellae, preventing a frequent collision of CO2 droplets and their fast coalescence. (c) 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46351.