Preparation and properties of functionalized polyorganosiloxanes

A series of linear functionalized polyorganosiloxanes of the type Me3SiO[MeSiO(CH2)nR]x(Me2S iO)ySiMe3, where n = 2, R = -(CH2)NMe2; n = 1, R = -(CH2)OEt; n = 4, R = -(CH2)COOEt; n = 3, R = -(CH2)Me, were prepd. and characterized. Functional group loadings of .apprx.4 mol% (x = 1, yr = 25), .apprx.11 mol% (x = 3, yr = 23), and .apprx.30 mol% (x = 8, yr = 18) were obtained by reacting com. available copolymers Me3SiO(MeSi{H} O)x(Me2SiO)ySiMe3 with the appropriate ratios of x:y, with the required quantities of HO(CH2)nR, using dichloro(1,5-cyclooctadiene)-platinum(II) as catalyst. Amine, ether, ester, and alkyl functionalized siloxanes were obtained in good yields after purifn., and each fluid polymer was characterized by 1H and 13C-NMR, and FTIR spectral measurements, elemental anal., viscosity, surface tension, and d. measurements. The functionalized polysiloxanes exhibit Newtonian behavior at shear rate 0.4 - 79.4 s-1, and significant viscosity enhancements were obsd. for all functionalized polymers compared with poly(dimethylsiloxane) fluids of similar chain length. The functionalized siloxanes exhibited in almost all cases an increase in both viscosity and d. as the functional group loading increased. The surface tension of the polymers was measured to be 18.8 - 22.3 mN m-1. [on SciFinder (R)]