Stress Relaxation in Concentrated Solutions of Polymethyl Methacrylate: Molecular Weight Dependence
- 1 July 1956
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 27 (7), 685-690
- https://doi.org/10.1063/1.1722466
Abstract
The measurement of stress relaxation in concentrated solutions of polymethyl methacrylate has revealed a relation between the spectrum of relaxation times, the weight average molecular weight, and the molecular weight distribution. The spectrum of relaxation times and the essentially identical theories developed by Rouse, Bueche, and Zimm are used to calculate an average relaxation time which is directly proportional to the weight average molecular weight. It is then shown that a first approximation to the distribution of molecular weights may be calculated if one assumes that the friction factor increases with the 1.5 power of the molecular weight. This distribution for selected samples of polymethyl methacrylate is compared with the Schulz distribution in which the parameters were obtained from light scattering and osmotic pressure experiments. The ratios Mz/Mw calculated from the theory and stress relaxation data on a rough fraction, a whole polymer, and a blend of two whole polymers are found to be 1.3, 1.7, and 1.9, respectively.Keywords
This publication has 14 references indexed in Scilit:
- Viscoelasticity of Poly MethacrylatesJournal of Applied Physics, 1955
- Slow Relaxation Mechanisms in Concentrated Polymer SolutionsThe Journal of Physical Chemistry, 1954
- The Viscoelastic Properties of PlasticsThe Journal of Chemical Physics, 1954
- Study of the viscoelastic behavior and molecular weight distribution of polyisobutyleneJournal of Polymer Science, 1953
- Higher approximations of relaxation spectraPhysica, 1952
- Mechanical Properties of Substances of High Molecular Weight. IX. Non-Newtonian Flow and Stress Relaxation in Concentrated Polyisobutylene and Polystyrene SolutionsJournal of Applied Physics, 1951
- Further Studies on the Melt Viscosity of Polyisobutylene.The Journal of Physical Chemistry, 1951
- Elastoviscous properties of polyisobutylene. I. Relaxation of stress in whole polymer of different molecular weights at elevated temperaturesJournal of Polymer Science, 1948
- The influence of reaction mechanism on size distribution in polymersTransactions of the Faraday Society, 1942
- The Conicylindrical ViscometerPhysics, 1934