PREPARATION AND ASSEMBLY OF NANOSIZED POLYMER LATEX

Monodispersed copolymer latexes of (styrene/butyl acrylate/acrylic aci d) with diameter of less than 100 nm were prepared by semicontinuous e mulsion polymerization using KPS (potassium persulphate) as initiator and SDS and OP (sodium dodecylsulfate and P-octylpolyethylene glycol p henylether) as cosurfactant. It was found that the particle size and s ize distribution were affected by the total emulsifier amount, the pre -added emulsifier concentration, the agitation speed and so on. The la tex particles were assembled into two-dimensional arrays on substrates . Owing to the surface groups such as -COOH and -SO4- derived from the comonomers and emulsifiers, the film formation to some degree, was af fected by the electrostatic interaction between two particles as well as by capillary force. Different electrolytes were added into the coll oid to adjust the particle interaction so that the attractive and repu lsive forces were properly balanced and the ordered arrays were obtain ed. (C) 1997 Elsevier Science S.A.