Siloxane Surface Activity

The structure, properties, and uses of poly(dimethylsiloxane) are surveyed in relation to its surface activity, with emphasis on the structural basis of this activity: the low intermolecular forces between methyl groups and the unique flexibility of the siloxane backbone. These basic attributes are used to explain the general interaction of poly(dimethylsiloxane) with high- and low-surface-energy substrates. The effects of variations of the pendant organic group and the backbone on surface activity are reviewed, and examples of current research and applications are given. The chief focus is on aliphatic fluorosilicones, because this class contains organosilicon polymers with the lowest surface energy. Information about organosilicon polymers with backbones other than siloxane is limited. The available data on polysilazanes, polysilalkylenes, and polysilanes are reviewed.