SYNTHESIS AND PROPERTIES OF FLUOROSILICON-CONTAINING POLYBUTADIENES BY HYDROSILYLATION OF FLUORINATED HYDROGENOSILANES .1. PREPARATION OF THE SILYLATION AGENTS

The synthesis of new fluorinated hydrogenosilanes CnF2n+1(CH2)(x)C2H4Si(CH3)(2)H with n=6 or 8 and x=0 or 1 is presented. Such compounds were prepared in 85%-90% yield by the selective reduction of the corresponding fluorine-containing (dimethyl)chlorosilanes. These chlorinated derivatives were produced by the hydrosilylation of (dimethyl) chlorosilane with perfluoroalkylvinyl, CnF2n+1CH=CH2 (x=0), or allyl, CnF2n+1CH2CH=CH2 (x=1), olefins, both obtained from perfluoroalkyl iodides in two steps, the latter olefins being more reactive than the former. For all these steps, the influence of the spacer (C2H4 or C3H6) located between the fluorinated chain and the silicon atom with respect to the reactivity is discussed.