Macroporous styrene-divinylbenzene copolymers : Formation of stable porous structures during the copolymerization

Content Provider	Semantic Scholar
Author	Erbay, Erol
Copyright Year	1998
Abstract	The variation of the pore structure of styrene-divinylbenzene (S-DVB) copolymer beads depending on the polymerization time was investigated. Macr oporous S-DVB copolymer beads with 10 mol % DVB content were prepared in the presence of cyclohexanol as a diluent. It was found that the stable pores in S-DVB copolymers mainly form at an early stage of the copolymerization, i.e., at the gel point. Thus, the early phase separated portions of the network, where the crosslink density is locally high, do not collapse on drying and illustrate the stable part of the porosity of S-DVB c opolymers. The number of stable pores does not change much during the whole course of the copolymerization. The maximum porosity first decreases on rising the post-gelation time due to the decreasing degree of dilution of the gel phase. Then, it increases continuously due to the increasing crosslink density of the gel. The pores formed at a later stage of the copolymerization are unstable and they collapse during the drying process. This is due to the lower crosslink density of the network regions forming later.
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://web.itu.edu.tr/okayo/pdf/98bullerol.pdf
Language	English
Access Restriction	Open
Subject Keyword	Bead Dosage Form CVB protocol Control theory Copolymer Copolymerization Cross link Cyclohexanol DILUENT DVB-S Digital Video Broadcasting Limited stage (cancer stage) Mole, unit of measurement Styrene Unstable Medical Device Problem divinylbenzene poly(glycidyl methacrylate-triallyl isocyanurate-divinylbenzene)
Content Type	Text
Resource Type	Article