ISSN:
0025-116X
Keywords:
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
,
Physics
Notes:
Intrinsic viscosities [η], second and third virial coefficients A2 and A3, respectively, and mean square radius of gyration 〈RG2〉 of a polymer homologous series of narrow-molecular-weight-distribution polystyrene samples in a molecular weight range of 2000 up to 24 · 106 were determined in toluene at 25°C by light scattering and viscometry measurements. The results are (3 · 104 〈 Mw 〈 24 · 106, Mw/Mn ≤ 1,3): \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} \left[ \eta \right]{\rm /}\left( {{\rm cm}^3 .{\rm g}^{{\rm - 1}} } \right){\rm = 8,62 } \cdot {\rm 10}^{{\rm - 3}} \cdot M_{\rm w}^{0,736} \\ A_2 /\left( {{\rm mol} \cdot {\rm cm}^3 .{\rm g}^{{\rm - 2}} } \right){\rm = 5,24} \cdot {\rm 10}^{{\rm - 3}} \cdot {\rm }M_{\rm w}^{ - 0,21} \\ A_3 /\left( {{\rm mol} \cdot {\rm cm}^6 .{\rm g}^{{\rm - 3}} } \right){\rm = 9,12} \cdot {\rm 10}^{{\rm - 6}} \cdot {\rm }M_{\rm w}^{0.58} \\ \left\langle {R_{\rm G}^2 } \right\rangle _{\rm W}^{{1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} /{\rm cm = 1,10} \cdot {\rm 10}^{{\rm - 9}} \cdot M_{\rm W}^{0.603} \\ \end{array} $$\end{document}These results were obtained by consideration of the limit of the dilute solution regime, the determination of zero-shear rate intrinsic viscosities, and the molecular weight dependence of the refractive index increment dn/dc. It was found that dn/dc increases slightly up to Mw = 1,8 · 106. A comparison of the [η]-Mw-relationship with literature data is given. In addition the unperturbed (theta) dimension parameters K0, 〈h2〉0/M, the characteristic ratio C∞, the steric factor σ, and the thermodynamic interaction parameter B were calculated from the modified Burchard-Stockmayer-Fixman procedure using polymolecularity correction and the results compared with experimental data from the literature.
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/macp.1983.021841021
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