Abstract: The applicability of universal calibration to star branched polystyrene was investigated by means of the apparatus of GPCcombined with a continuous viscorneter and a low angle laser light scattering photometer.The results show that the universal calibration is applicable to fractions of star branched polystyrene when their branched parameter g' (=[η]_b/[η]_l) is equal to or greater than 0.131z` but not to the higher branched fractions with g' <0.131.

Key words: GPC-continuous viscometer-low angle light scattering photometer, Long chain branching, Star-shaped polystyrene, Universal calibration