SYNTHESIS AND THERMAL-BEHAVIOR OF ALPHA,OMEGA-DI(METHACRYLOYLOXY)-POLY(ETHYLENE OXIDE-BLOCK-STYRENE-BLOCK-ETHYLENE OXIDE)

alpha,omega-Di(methacryloyloxy)-poly(ethylene oxide-block-styrene-bloc k-ethylene oxide) macromonomer has been synthesized by ''living'' anio nic polymerization initiated by potassium naphthalene, High vacuum tec hnique has been used in order to obtain a macromonomer with an end fun ctionality close to two. Two macromonomer fractions of different molec ular weights and compositions were isolated from the reaction mixture, according to their solubility in methanol. They displayed the expecte d chemical structure, as confirmed by H-1-NMR. The number average mole cular weights (M-n) of the fractions were 3400 and 660, respectively, and the average functionality was around two in both cases. DSC invest igation of the thermal behavior of both fractions showed no phase sepa ration inside the macromonomer. Thermostability of the low molecular w eight fraction was lower than that of the high molecular weight fracti on due to the larger proportion of ethylene oxide units.