Reactive poly(glycidyl methacrylate) microspheres prepared by dispersion polymerization

Poly(glycidyl methacrylate) [poly(GMA)] microspheres of narrow size distrib ution were prepared in a simple one-step procedure by dispersion radical po lymerization. Depending on the solvent used, poly(GMA) particle size could be controlled in the range of 0.5-4 mu m by changing the solubility paramet er of the reaction mixture. In N,N'-dimethylformamide (DMF)/methanol mixtur e, the particle size increased and the size distribution broadened with dec reasing initial solubility parameter. While in the DMF/methanol solvent sys tem, hydroxypropyl cellulose (HPC) or cellulose acetate butyrate (CAB) were taken as steric stabilizers of the dispersion polymerization, poly(vinylpy rrolidone) (PVP) was used in alcoholic media. Contrary to the DMF/methanol system, narrow particle size distributions were obtained with PVP-stabilize d polymerizations in ethanolic, methanolic, propan-1-olic or butan-1-olic m edium. Both the particle size and polydispersity were reduced with increasi ng stabilizer concentration. If lower molecular-weight PVP was used, larger microspheres were obtained. Poly(GMA) samples prepared in a neat alcoholic medium virtually quantitatively retained oxirane group content after the p olymerization. Reactivity of the poly(GMA) microspheres was confirmed by th eir hydrolysis and aminolysis. (C) 2000 John Wiley & Sons, Inc.