The branched polymers with different branching structures were synthesized through atom transfer radical polymerization (ATRP) via controlling the adding method of divinylbenzene (DVB). The four-arm star polymers with different arm length were also prepared by ATRP as the reference for branching structure characterization. Triple detection size exclusion chromatography (TD-SEC) analysis showed that the exponential factor ε had a strong molecular weight dependence

here

ε (g’=g

ε

) is the branching structure parameter expressed by Zimm branching factors g’=[Intrinsic Viscosity]

branched

/[Intrinsic Viscosity]

linear

and g= [Mean Square Radii of gyration]

branched

/[Mean Square Radii of gyration]

linear

at the same molecular weight. The average ε value of star-like branched polymers was less than unity

and remained relatively constant with the change of molecular weight; while the average ε value of randomly branched polymers was larger than unity

and decreased gradually with increased molecular weight. Therefore

the polymer branching structure can be characterized using TD-SEC.