Model Filled Polymers. 6. Determination of the Crosslink Density of PolymericBeads by Swelling

摘要

A new method has been developed to characterize the crosslink density ofmonodisperse polymeric microbeads by equilibrium swelling on an ultrafiltration membrane, followed by the removal of excess solvent by centrifugation. For polystyrene copolymerized with divinylbenzene and polymethyl methacrylate copolymerized with ethylene glycol dimethacrylate, the mole percent of crosslinked units, approximated, but always exceeded, the mole percent of divinyl monomer. Crosslink densities were varied from 1-11%. Keywords: Crosslink density; Equilibrium swelling, Filled polymers; Crosslinked monodisperse beads; Polymer beads. (jes)