PRODUCTION OF SUBMICRON SIZED MULTIHOLLOW POLYMER PARTICLES BY ALKALICOOLING METHOD/

Submicron-sized styrene-methacrylic acid copolymer particles, which we re produced by emulsion copolymerization, were changed to those having multihollow structure by treating stepwise the emulsion as follows. F irst alkali treatment was carried out at higher temperature than the g lass transition temperature and subsequently the emulsion was cooled b y keeping it at room temperature. This was named ''alkali/cooling meth od''. The effects of methacrylic acid content, pH, time and temperatur e in the alkali treatment on the formation of multihollow structure we re clarified.