SPECTRAL CHARACTERIZATION AND THERMAL-BEHAVIOR OF CROSS-LINKED POLY(HYDROXYETHYLMETHACRYLATE) BEADS PREPARED BY SUSPENSION POLYMERIZATION


KIREMITCI M., CUKUROVA H., OZKAR S.

POLYMER INTERNATIONAL, vol.30, no.3, pp.357-361, 1993 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 30 Issue: 3
  • Publication Date: 1993
  • Doi Number: 10.1002/pi.4990300313
  • Journal Name: POLYMER INTERNATIONAL
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.357-361
  • Middle East Technical University Affiliated: Yes

Abstract

Crosslinked poly(hydroxyethylmethacrylate) [poly(HEMA)] beads were prepared by the suspension copolymerization of 2-hydroxyethylmethacrylate monomer with ethyleneglycol dimethacrylate (EGDMA) in aqueous media which contained only magnesium oxide (MgO) as a suspension stabilizer and also salting-out agent. The procedure gives spherical particles with narrow size distribution. The reaction mechanism, composition and structure of poly(HEMA) beads were studied by solid-state C-13 CP/MAS NMR, FTIR, ESCA, and elemental analysis. C-13 NMR implies the existence of unreacted pendant groups in the HEMA-EGDMA copolymer. The surface composition obtained by ESCA is almost the same as the bulk composition determined by elemental analysis. FTIR spectra provide compelling evidence for the presence of carboxyl and hydroxyl groups. The glass-transition temperature and the thermal stability of beads were determined by DSC.