SILICON-MODIFIED CARBOHYDRATE SURFACTANTS .5. THE WETTING BEHAVIOR OFLOW-MOLECULAR-WEIGHT SILOXANE, CARBOSILANE, SILANE AND POLYSILANE PRECURSORS ON LOW-ENERGY SURFACES

The surface tensions, wetting tensions, contact angles and solid/liqui d interfacial tensions of defined siloxanes as well as those of analog ous carbosilanes, polysilanes and neopentyl substituted silanes were d etermined, The wetting experiments were carried out on a glass plate c oated with perfluoroalkyl methacrylate (FC 722 (R)), The siloxanes pos sess the lowest surface tensions, Due to the presence of oxygen atoms in the siloxane backbone, a donor-acceptor portion (gamma(lv)(+/-)) of the surface tension of about 1-2 mN/m was determined, The solid/liqui d interfacial tension also contains a donor-acceptor portion (gamma(sl )(+/-)). Its value is almost identical to that of gamma(lv)(+/-) The /- differences between individual molecules gamma(sl)(+/-)differences between individual molecules of the same surface tension are responsib le for contact angle differences of up to 4 degrees. (C) 1997 by John Whey & Sons, Ltd.