abstract |
The invention concerns preparation of porous copolymer beads by a seeded polymerization process employing gel copolymer seed particles. The process comprises initially providing a plurality of gel-type copolymer seed particles prepared by polymerization of at least one first monovinylidene monomer and a first cross-linking monomer. A second monomer mixture comprising at least one second monovinylidene monomer, a second cross-linking monomer, and a phase-separating diluent is thereafter imbibed by the seed particles and polymerized therein. The process is characterized by selecting the first monovinylidene monomers such that the phase-separating diluent and second monovinylidene monomers are capable of being imbibed by the seed particles in an amount sufficient to form a porous copolymer. The porous copolymer beads produced have stable polymeric structures and good physical properties that render them useful in preparing ion-exchange resins and polymeric adsorbents. |