## Abstract Ultrasonic degradation of high molecular weight poly(vinylpyrrolidone) is monitored on‐line, by light scattering. Degradations are performed in water/methanol mixtures of various compositions at room temperature. The evolutions of the weight average molecular weight and the radius of gy
Conformational characteristics of poly(vinylpyrrolidone). solvent-dependence of the chain dimensions
✍ Scribed by Tarazona, María Pilar ;Saiz, Enrique ;Gargallo, Ligia ;Radic, Deodato
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1993
- Weight
- 652 KB
- Volume
- 2
- Category
- Article
- ISSN
- 1018-5054
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✦ Synopsis
Abstract
Conformational energies as function of rotational angles over two consecutive skeletal bonds for both meso and racemic diads of poly(__N__vinyl‐2‐pyrrolidone) have been computed. The results of these calculations were used to formulate a statistical model that was then employed to calculate the unperturbed dimensions of this polymer. The conformational energies are sensitive to the Coulombic interactions, which are governed by the dielectric constant, of the solvent, and to the size of the solvent molecules. Consequently, the calculated values of the polymeric chain dimensions are strongly dependent on the nature of the solvent, as it was experimentally found before.
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