A series of novel polymers have been prepared by free radical solution polymerization of a variety of hydrocarbon monomers with the (perfluoroalkyl)ethyl methacrylate monomer H2CC(CH3)CO2(CH2)2(CF2) n F, 1 (n̄ ≈ 7.7). Polymers prepared using two different methods of feeding 1 into the reaction mass are discussed. Through a judicious choice of reaction conditions, some control of polymer architecture was exhibited. The resultant (perfluoroalkyl)ethyl methacrylate-containing acrylic polymers were shown to be quite surface active in the solid state. The magnitude of surface activity depends on the monomer 1 feed method. The polymers were formulated into thin films and applied to a variety of surfaces. With levels at 1.5 wt % of 1, water and oil repellent surfaces were created. Water contact angles (advancing) of ∼80−115° and hexadecane contact angles (advancing) of ∼60−70° were observed routinely. In addition, it was observed that the concentration profile of fluorine in the films exhibited a steep gradient normal to the surface when studied by angle-dependent ESCA and secondary ion mass spectroscopic depth profiling.

Lightly cross-linked films were made by solvent casting hydrocarbon polyester solutions containing trace fluorocarbon in the bulk and then curing or cross-linking the film to anchor the fluorine groups. The surface nano-morphology was studied by AFM techniques based on tapping mode AFM which allows very low contact forces and gives indirect surface chemical mapping of different domain morphologies with high lateral resolution. The contrast is usually from different local stiffness variations of domains at or near the surface. More conventional friction force microscopy techniques were also applied to verify the results. The percent coverage of fluorine-rich domains was quantitatively related to that determined from hexadecane contact angles. A low-coverage self-assembled octadecyltrichlorosilane (OTS) monolayer system, exhibiting nano-patches on Si substrate, was used as a control for a newly applied ultra-light-tapping technique which derives its chemical resolution from hydrophilicity differences of the phases at the surface. The hydrophilicity differences possibly modify the water meniscus forces on the scanning tip and allow indirect assignment of domains based on different hydrophilicities in cases where there are no a priori stiffness assignments of the different domains.

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