NEW FLUORINATED POLYSILOXANES CONTAINING AN ESTER FUNCTION IN THE SPACER .1. SYNTHESIS AND CHARACTERIZATION

Unsaturated perfluoroalkyl esters derived from undecylenic acid: CH2=C H-(CH2)8-COO-CH2-CH2-R(F) (with R(F) = C6F13, 2a and R(F) = C8F17, 2b) and C8F17-(CH2)10-COO-CH2-CH=CH2, 2c were prepared with excellent yie lds. Their hydrosilylation by methylhydrodimethylsiloxane copolymers o f various Si - H contents gives new fluorinated polysiloxanes which we re examined by H-1- and C-13-NMR, GPC, differential scanning calorimet ry, and optical polarizing microscopy. Polymers derived from compounds 2a and 2b exhibit mesomorphic structures. (C) 1994 John Wiley & Sons, Inc.