Preparation and characterization of microemulsion with high solid content of copolymerized acrylate/styrene

Microemulsion with high solid content of quadribasic co-polymer of polystyrene(St),methyl acrylate,butyl acrylate and acrylic acid was prepared by seeded emulsion polymerization method using ammonium per-sulfate as initiator,a reactive emulsifier alkylamide ethylene sulfonate(DNS-86)and ethoxylated octylphenol(OP-10)as complex emulsifier and n-pentanol(n-PTL)as co-emulsifier.The effects of the ratio between the monomers,the dosages of the emulsifiers and the initiator on the property of the emulsions and particle size were discussed.The microemulsion was analyzed with FT-IR,DSC and the results showed that free radical polymerization happens among styrene and the acrylates.Through TEM observation,the average particle size of the polymer is determined as 35 nm.When m(BA)∶m(St+MA)=4∶6 and m(DNS-86)∶m(OP-10)∶m(n-PTL)=11∶3∶2,with initiator dosage of 0.7% of the total monomers,the emulsion shows good property and the particle size is within nanometer range.