## Abstract In this paper we examine a series of hydrocarbons with structural features which cause a weakening of the CH bond. We use theoretical calculations to explore whether the carbon‐centered radicals R^•^ which are created after breaking the bond can be stabilized enough so that they resist
Effect of Additional Hydroxyl Functionalities on the Hydrolytic Stability of Oligoesters
✍ Scribed by Mark D. Soucek; Aaron H. Johnson; Leon E. Meemken
- Publisher
- John Wiley and Sons
- Year
- 2004
- Tongue
- English
- Weight
- 114 KB
- Volume
- 205
- Category
- Article
- ISSN
- 1022-1352
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✦ Synopsis
Abstract
Summary: The addition of a trifunctional polyol (trimethylolpropane) to oligoesters comprised of hexahydrophthalic anhydride, cyclohexane‐1,4‐dicarboxylic acid, cyclohexane‐1,3‐dicarboxylic acid, neopentyl glycol, and cyclohexane‐1,4‐dimethanol was investigated via an accelerated hydrolysis environment. The oligoesters were dissolved in an acetone/water solution, and the hydrolysis was evaluated by monitoring carboxylic acid formation and by measurement of the molecular weight shift by size exclusion chromatography. Aliquots of the oligoester solution were evaluated intermittently over a 36‐week period. Both the initial rate and the overall rates of hydrolysis were reported as hydrolysis velocities. The influence of hydroxyl concentration is apparent in the initial velocity of hydrolysis. After the induction period, steric effects appear to be the controlling factor for the retardation of main chain scission.
A comparison of the initial and final rates of hydrolysis as a function of oligoester composition.
imageA comparison of the initial and final rates of hydrolysis as a function of oligoester composition.
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