Telechelic oligosiloxanes are obtained either via ring opening polymerizati
on of polycyclodialkylsiloxane or via hydrosilylation with a alpha,omega -b
is hydrosilane oligosiloxane or via condensation between a alpha,omega -bis
hydroxy oligosiloxane and an appropriated chlorosilane. This study investi
gates the synthesis of a alpha,omega -bis anhydride oligosiloxane via hydro
silylation of bicyclo[2.2.1]hept-5-ene-endo-2,3-dicarboxylic anhydride with
alpha,omega -bis hydrosilane oligosiloxane in the presence of a Platinum c
atalyst. Using a Pt catalyst induced a long reaction time and especially an
important increase of average molecular weight. Another method of synthesi
s in two steps was then set up: condensation of exo,5-(dimethylchlorosilyl)
bicyclo-[2.2.1]heptane-endo-2,3-dicarboxylic anhydride with alpha,omega -bi
s hydroxy oligosiloxane which leads to the expected oligosiloxane, rapidly
and quantitatively. Thermal properties have also been investigated alpha,om
ega -bis anhydridr oligosiloxane may take part in the synthesis of block co
polymers. (C) 2001 Elsevier Science Ltd. All rights reserved.