ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
The radius of gyration Rg and the hydrodynamic radius Rh for branched (denoted by subscript b) and linear (1) polystyrenes of different molecular weights were measured both in theta- and good solvents. The ratios gg ≡ Rgb/Rgl, gh ≡ Rhb/Rhl, and Rh/Rg were calculated and compared with theoretical predictions based on the Kurata-Fukatsu theory and its extention to good solvent systems. The following observations were made: gg/ggΘ 〈 gh/ghΘ 〈 1 and (Rh/Rg)1 〈 (Rh/Rg)b 〈 1. The expansion coefficients αg and αh are reduced by the incorporation of branching. Theoretical predictions are qualitatively consistent with these results. The second virial coefficient of branched polymers has a larger molecular-weight dependence than that of linear polymers, which was explained by a smaller molecular-weight dependence of Rg. The penetration function of branched polymers is about three times as large as that of linear polymers.
Additional Material:
10 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1987.021880417
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