Showing papers by "Kenneth A. Mauritz published in 1987"
TL;DR: In this article, the volume swelling ratios of individual PVC particles, immersed in excess plasticizer, were recorded over a period of time using an optical microscope equipped with a high speed camera, Absorption of din-decylphthalate was studied in the range 70 < T < 100°C.
Abstract: The kinetics of plasticizer absorption by suspension polymerized polyvinylchloride (PVC) have been investigated. The volume swelling ratios of individual PVC particles, immersed in excess plasticizer, were recorded over a period of time using an optical microscope equipped with a high speed camera, Absorption of din-decylphthalate was studied in the range 70 < T < 100°C. The study shows that the uptake of plasticizer proceeds in three steps: (1) a slow initial absorption into glassy PVC, which is a thermally activated rate process, wherein the polymer is being progressively solvated and evolving toward the rubbery state, (2) the considerable faster diffusion of plasticizer into a rubbery, dynamic polymer matrix, and (3) the asymptotic approach to the equilibrium swelling capacity. Temperature dependency of rate of absorption in the slow initial step was fitted to an Arrhenius expression, and an activation energy for plasticizer uptake was calculated.
4 citations
01 Jan 1987
TL;DR: A critical review of these contributions with a view toward identifying areas that demand improvement or development as well as provide a general enumeration of concepts for the uninformed is provided in this paper.
Abstract: A number of theoretical molecular energetics-based models of polar/nonpolar aggregation in ionomers have developed in concert with the proliferation of an experimental structure/properties database in this area. This manuscript is a critical review of these contributions with a view toward identifying areas that demand improvement or development as well as provide a general enumeration of concepts for the uninformed. A distinction is made between dry vs. hydrated ionomers and hydrocarbon-based ionomers with low ionic mole fractions vs. perfluorinated ionomers. It is also concluded that, while the existing models have come a long way in explaining observed overall structural features and properties trends, the goal of fine-tuning novel ionomer materials for a broad range of applications, using a comprehensive model, remains unattained.
2 citations