on t´ ermica de fibras de coco con tratamiento qu´ provenientes de mezclas de concreto (estudio cin´ etico).

The aim of this work was to study the kinetics of thermal degradation of coconut fibers untreated and treated, extracted from the cement matrix at di erent concentrations and ages of curing, by thermogravimetric analysis. In calculating the temperature of onset (onset) and end (endset) decomposition of the fiber is used the method of integrating the first derivative. The integral method proposed by Coast-Redfern was used to determine the kinetic parameters in the degradation of the fibers from the temperature and mass data generated by the TGA, for a constant heating rate and an inert atmosphere of nitrogen. It was found that the fibers undergo further degradation in the cement matrix to the extent that increase the days of curing. Untreated fibers with short size distribution have an increased decomposition in the cement matrix containing fibers , as corroborated by the activation energy for 128 days of curing. Chemical treatment with PMMA fibers protects alkaline etching of concrete at di erent ages of curing. Likewise thermogravimetric analysis allows to conclude that factors such as the days of curing, the percentage by volume and the size distribution of the fibers to be significant on the resistance of concrete mixtures.