Preparation of BA/ST/AM nano particles by ultrasonic emulsifier-free emulsion polymerization

A kind of nano particle of butyl acrylate (BA)/styrene (ST)/acrylamide (AM) was prepared through a new method that was ultrasonic emulsifier-free emulsion polymerization, which was a kind of environmental protection and economical method. And no any volatile organic solvent (VOC), emulsifier and initiator were used in this method. Only water was used as solvent. The effects of sonic intensity, sonic time, inorganic salt content, N2 flow velocity, etc. on monomer conversion were studied. TEM photographs showed that its particles size was about 80 nm, which was less than particles size (about 140 nm) through conventional emulsifier-free emulsion polymerization method. The FTIR spectrum showed that after extracted by water for 48 h, CHCl3 for 48 h and THF for 48 hr, respectively, the sample obtained by this way was a ternary copolymer of BA, ST and AM, but not a blend of poly(butyl acrylate), polystyrene and polyacrylamide.