ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Dipole moments of poly(4-methoxystyrene) (PMeOSt) and poly(4-bromostyrene) (PBrSt) were determined from dielectric constant and density measurements on dilute solutions of the polymers in benzene, 1,4-dioxane and toluene, over the range of temperatures from 25 to 55°C. The average dipole moments per constitutional repeating unit (μ) obtained in benzene (Bz), 1,4-dioxane (Dox), and toluene (Tol) at 25°C are as follows: 1,219 D (Bz), 1,253 D (Dox) and 1,175 D (Tol) for PMeOSt, and 1,371 D (Bz) and 1,413 D (Dox) for PBrStIn SI units: 1 D ≈ 3,33564 · 10-30 C · m.. The dipole moment ratio, Dr = 〈μ2〉2/μ20, was found to be 0,942 for PMeOSt and 0,467 for PBrSt in Bz at 25°C, for which the observed values of the dipole moments of 4-methoxytoluene and 4-bromoethylbenzene were used as μ0 for the respective polymer. The variation of the dipole moment ratio with temperature was linear but very small, dDr/dT giving a negative value for PMeOSt but a positive value for PBrSt.
Additional Material:
3 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1991.021920306
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