Sodium sulfonate terminated polystyrene(PS-SO3Na) was synthesized by atom transfer radical polymerization of styrene with 2′-(p-sulfophenyl)ethyl 2-bromoisobutyrate ao initiator

and the resulting polymer reacted with NaOH. The initiator was lyntheaized from 2-phenylethanol and 2-bromoisobutyryl bromide. Polymer brushes constructed on the surface of cationically functionalized SiO2(SiO2-CBAFS) were prepared via electrostatic-assembly between PS-SO3Na and SiO2-CBAFS.IR

1H-NMR

TG

TEM

AFM

GPC and water contact angle were used to characterize the structure

the assembly amount and the regularity of the assembly system.The results show that PS-SO3Na can be synthesized with 2′-(p-sulfophenyl)ethyl 2-bromoisobutyrate successfully

the assembly efficiency is increased in some extent with the polymer terminated 100% sodium sulfonate

and the amount of polymer brushes assembled on the surface of SiO2 is as high as 34.4%;white layers can be observed at the surface of SiO2 colloid particles with TEM

and the dispersion of SiO2 is modified obviously; the descent of water contact angles of the samples below 4° when the rinsed solvents altered from THF to H2O; the decorate effect of SiO2 is preferable when the molecular weight of PS-SO3Na range from 1.5×104 to 3.6×104 and the molar concentration of polymer solutions range from 2.5×10-5 mol/L to 5×10-5 mol/L with the analysis of the results of TG

AFM and water contact angles.