Degradation of sisal fibre/Mater Bi-Y biocomposites buried in soil

VERA ALVAREZ; ROXANA RUSCEKAITE; ANALÍA VÁZQUEZ

POLYMER DEGRADATION AND STABILITY

Elsevier

Año: 2006 vol. 91 p. 3156 - 3162

0141-3910

Degradation of short sisal fibres/Mater Bi-Y
biocomposites during indoor burial experiments was analysed. Within the first month, watersorption was the main event followed by weight loss. Water sorption results demonstrated that composites absorbed less water than the matrix. The lower sorption capacity of composites was related to the presence of fibreefibre and fibreematrix (both of carbohydrate nature) interactions which prevents the water intake and enhances the material stability. In soil burial, all materials followed the same degradation pattern. The amorphous nature of the matrix favoured the preferential removal of starch, which was the most bio-susceptible material, as observed by thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). Fibres seemed to play a secondary role in this process, as confirmed by the slight difference in weight loss between the matrix and composites (40 and 33 wt.%, respectively). The drop in mechanical properties as a function of the exposure time was associated with the preferential loss of matrix and fibre components and the detriment of the fibre/matrix interface.