Starch Michael S, Fiori Jean E, Lin Zuchen
Dow Corning Corporation, P.O. Box 994, Midland, MI 48686-0994, USA.
J Cosmet Sci. 2003 Mar-Apr;54(2):193-205.
The development of silicone elastomers with hydrophilic functionality in the form of PEG substituents provides benefits beyond the rheology modification (thickening) that can be achieved with silicone elastomers that lack functional substituents. We have shown that PEG-modified dimethicone crosspolymer (PEG-DCP) is an effective emulsifier for water-in-silicone (w/s) emulsions where the continuous phase is cyclopentasiloxane. The utility of PEG-DCP for producing simple antiperspirant gels and also multiple emulsions (w/s/w) was demonstrated. Additional benefits for PEG-DCP such as improved compatibility with polar organic oils and reduced syneresis in anhydrous antiperspirants were also shown to be associated with the addition of hydrophilic groups to the silicone elastomer. The performance and physical properties of a series of PEG-DCP samples from a two-level factorial design were evaluated. The variables studied were the level of PEG substitution, the length of the PEG chains, and crosslink density. All of the PEG-DCP samples were synthesized and tested in the form of dispersions in cyclopentasiloxane. Variations in the composition of PEG-DCP such as the level of PEG substitution and the length of the PEG chain were shown to have a significant effect on the viscosity of the PEG-DCP and its emulsification performance in a simple w/s emulsion. Variation of a process parameter that affects the crosslink density of the elastomer also changed the emulsification properties of the PEG-DCP.
具有聚乙二醇（PEG）取代基形式的亲水性官能团的有机硅弹性体的开发，其带来的好处超出了缺乏官能取代基的有机硅弹性体所能实现的流变学改性（增稠）效果。我们已经表明，聚乙二醇改性二甲基硅氧烷交联聚合物（PEG-DCP）是一种有效的乳化剂，可用于连续相为环戊硅氧烷的硅包水（w/s）乳液。PEG-DCP在生产简单止汗凝胶以及多重乳液（w/s/w）方面的效用得到了证明。PEG-DCP的其他优点，如与极性有机油的相容性提高以及无水止汗剂中脱水收缩的减少，也被证明与向有机硅弹性体中添加亲水性基团有关。对来自两水平析因设计的一系列PEG-DCP样品的性能和物理性质进行了评估。所研究的变量为PEG取代水平、PEG链的长度和交联密度。所有PEG-DCP样品均以在环戊硅氧烷中的分散体形式合成并进行测试。PEG-DCP组成的变化，如PEG取代水平和PEG链的长度，对PEG-DCP的粘度及其在简单w/s乳液中的乳化性能有显著影响。影响弹性体交联密度的工艺参数的变化也改变了PEG-DCP的乳化性能。
