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Updated: Sep 30, 2026

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Published on: October 30, 2013
Kinetics of anhydride formation in xerogels of poly(acrylic acid)
H Blanco-Fuente1, S Anguiano-Igea, F J Otero-Espinar
1Departamento de Farmacología, Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Santiago de Compostela, Spain.
Abstract:
The aim of this work was to study the cross-linkage of xerogels made of Carbopol of different molecular weight (polymers deriving from polyacrylic acid), and the influence exerted by different percentages of beta-cyclodextrin upon the cross-linkage percentage. Xerogels were obtained by high-pressure compression and cross-linking was studied by measuring the weight loss of different formulations over a temperature range of 70 to 190 degrees C. Kinetics of anhydride formation were found to follow a second-order mechanism with an activation energy of approximately 25 kcal mol-1.
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