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Título: The study of poly(Divinylbenzene-co-ethylvinylbenzene) and modifications to the pendant vinylbenzene groups /
Autores: Hubbard, K. Lise (Kirsten Lise-Lotte)
Fecha: 1997
Publicador: McGill University
Fuente: Ver documento
Tipo: Electronic Thesis or Dissertation
Tema: Chemistry, Polymer.
Descripción: Cross-linked resins of poly(divinylbenzene-co-ethylvinylbenzene) were characterized and modified by a variety of reactions with the pendant vinylbenzene groups. Laboratory-prepared resins of a known composition were compared and contrasted to a commercial version with regard to surface area, porosity, and vinylbenzene content. The commercial resin, Amberlite XAD-4 (Rohm and Haas Company), had a higher surface area (831 m2 /g), porosity (1.18 mL/g), and accessible vinylbenzene groups (2.5 mmol/g, degree of functionalization 33%). Modifications of both resins by radical addition of a variety of thiols led to higher conversions (of vinylbenzene groups to modified groups) with use of the commercial resin (as high as 76%). Further modifications were done strictly with XAD-4. Some thiol additions to XAD-4 were done with water as the solvent, with conversions as high as 43%. Disulfides were added across the vinylbenzene groups of XAD-4 with iodine catalysis, with conversions as high as 55%. This simple one-step reaction has never been done with a polymer system before. XAD-4 was completely epoxidized using a solution of dimethyldioxirane in acetone, and completely brominated to form a resin with (1,2-dibromoethyl)benzene groups (3.76 mmol Br/g). Resins with (1-hydroxy-2-bromoethyl)benzene groups (1.5 mmol/g) were prepared by reaction of XAD-4 with N-bromosuccinimide and water, with 73% conversion. Resins with thiol groups (2.5 mmol S/g) were prepared by a one-pot reaction of brominated XAD-4 with N,N-dimethylthioformamide followed by methanolysis. From one commercially-available resin, several polymers with a variety of functional groups have thus been prepared by simple one- to three-step modifications.
Idioma: en