6533b7ddfe1ef96bd127551f
RESEARCH PRODUCT
Continuous spin fractionation and characterization by size-exclusion chromatography for styrene-butadiene block copolymers.
John EckeltLina ZhangXiaopeng XiongZhengjun ZhangBernhard A. Wolfsubject
Styrene-butadieneChromatographyOrganic ChemistryDispersitySize-exclusion chromatographyGeneral MedicineFractionationBiochemistryAnalytical ChemistryStyreneGel permeation chromatographyMolecular Weightchemistry.chemical_compoundchemistryCopolymerButadienesChromatography GelMolar mass distributionPolystyrenesStyrenedescription
Abstract Linear and star-shaped styrene–butadiene block copolymers synthesized by anionic polymerization of butadiene and styrene were fractionated by applying a newly developed large-scale fractionation technique, named continuous spin fractionation (CSF). Their molecular weight and polydispersity index ( d = M w / M n ) were measured with size-exclusion chromatography and static light scattering. For the linear triblock copolymer a fractionation via temperature variation turned out to be better suited than the usual isothermal procedure. The star-shaped polymer with the d value of 1.33 was fractionated in two CSF steps to get the targeted sample, which has a considerably more uniform structure and a narrower molecular weight distribution ( d = 1.11). The corresponding starting linear diblock copolymer was fractionated in one step reducing d from 1.68 to 1.17. With one set of simple laboratory equipment, 1 kg polymer can be fractionated per day. Utilizing CSF, for the first time, we fractionated successfully the block copolymers.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-10-18 | Journal of chromatography. A |