ISSN:
0022-3832
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Measurements of intrinsic viscosity and light scattering were made on fractions of polymers prepared by the redox polymerization of styrene in the presence of oxidized polystyrene or copolymers of skyrene and 4-vinylcyclohexene-1. For comparison, similar measurements were made on fractions of linear polystyrene. The conclusion that branching had taken place by graft polymerization was confirmed. Values found for the intrinsic viscosity, the molecular size, and the second virial coefficient were generally lower for fractions of the graft polymers than for fractions of linear polystyrene of the same molecular weight. It was also observed that fractionation of the graft polymers took place with respect to molecular size, not molecular weight, and that the most highly branched fractions were the most soluble. A comparison of experimental values of the branching ratio g with values calculated for a model having linear branches equally spaced along a backbone chain indicates that the graft polymers contain up to at least 6 branches per molecule. Values of Huggins' k′ for these branched molecules did not differ significantly from those for linear polystyrene (0.30 〈 k′ 〈 0.40). It is concluded that though k′ is sensitive to bushy branching, it is not measurably affected by the presence in the polymers of a few linear branches per molecule.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1958.1203312619
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