Loss of mechanical properties by water absorption of vinyl-ester reinforced with glass fiber

ORLANDO DE LA OSA; VERA ALVAREZ; ALICIA FRAGA; EZEQUIEL MARTINEZ MAMMONE; ANALÍA VÁZQUEZ

Journal of Reinforced Plastics and Composites

SAGE Publications

Año: 2006 vol. 25 p. 215 - 221

1530-7964

The effect of water absorption on the mechanical properties of the composites has been studied. The matrix used was vinyl-ester. Different arrangements of glass fibers were used to  reinforce vinyl-ester matrix: mat, unidirectional, and bidirectional cloth. The samples were immersed in distillated water at 80
C. The flexural modulus was measured as a function of immersion time. The decrease in the glass transition emperature, Tg, was correlated with the water absorption and flexural modulus. The composite flexural modulus was fitted by means of a modified rule of mixture, which included an interfacial coefficient. The relationship between the directionality of the fiber in the composite material and the water absorption was also analyzed.
C. The flexural modulus was measured as a function of immersion time. The decrease in the glass transition emperature, Tg, was correlated with the water absorption and flexural modulus. The composite flexural modulus was fitted by means of a modified rule of mixture, which included an interfacial coefficient. The relationship between the directionality of the fiber in the composite material and the water absorption was also analyzed.