3′-trifluoropropyl)cyclotrisiloxane (II), and hexamethylcyclotrisiloxane (D 3 ) (III), respectively, in 1,1,3,3-tetramethyldisiloxane (TMDS). Solutions of a UV-sensitive diaryliodonium salt (0.5 wt %) and oligomers VII-IX were cast as uniform layers onto clean glass microscope slides and steel coupons. UV irradiation of these liquid layers rapidly converted them to cross-linked films (X-XII). Thermal stability of these films was determined by thermogravimetric analysis (TGA). Glass transition temperatures (T g s) were measured by dynamic mechanical thermal analysis (DMTA). Static contact angles of distilled water on the air-film interfaces of X-XII have been determined with a goniometer. Dynamic contact angle (DCA) measurements have also been carried out on free-standing films. Corrosion protection of steel coupons by X-XII was evaluated by electrochemical impedance spectroscopy (EIS) during exposure to 0.5 N NaCl. Antifoul and foul-release properties of X-XII were studied by settlement and removal tests with the barnacle Balanus amphitrite and with spores and sporelings of the green alga Enteromorpha.

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Polydiphenylsiloxane–polydimethylsiloxane–polydiphenylsiloxane triblock copolymers were prepared by two methods. The first approach was the sequential addition of the monomers. The anionic polymerization of hexamethylcyclotrisiloxane initiated by dilithio diphenylsilanolate gave α,ω‐bis(lithio dimethylsilanolate)polydimethylsiloxane, which was added to hexaphenylcyclotrisiloxane at ∼120 °C to yield the desired triblock material. In the other, a convergent approach was used. Excess α‐vinyldimethylsiloxypolydiphenylsiloxane was coupled to α,ω‐bis(hydrido)polydimethylsiloxane by a Pt‐catalyzed hydrosilylation reaction to give the triblock material. The formation of distinct blocks with regular microstructures in these materials was confirmed by 1H, 13C, and 29Si NMR spectroscopy as well as differential scanning calorimetry. The molecular weights were determined by gel permeation chromatography, and the thermal stabilities were evaluated by thermogravimetric analysis. Dynamic mechanical analysis was used to confirm thermal transitions obtained by differential scanning calorimetry and to evaluate the mechanical properties of the materials. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3629–3639, 2006