Evaluation of jute fiber preforms absorbability using optical profilographometer

Abstract

The article presents an analysis of absorbability of polyester resin by jute fabric – untreated and treated in KOH water solutions (various exposure times), toluene diisocyanate, methanol, vinyl acetate and vinylsilane. A change with time in height of a resin droplet put on the fabric specimen was measured using optical profilographometer. The height of droplet was taken as a criterion of absorbability. Additional profilometric scanning observations, scanning electron microscopic observations and a saturation time in vacuum resin infusion tests were conducted in order to confirm and explain the results of the droplet height measurements. Although scanning electron microscopic analysis showed improvement in wetting between the treated fibers and the resin, the droplet height measurements showed that chemical treatment impairs translaminar absorbability of jute fabric. Deterioration of absorbability is caused by swelling of jute strands. However, technological tests showed that in most cases the treatment shortens the saturation time, which testifies an improvement in in-plane absorbability. Especially treatment with vinylsilane and KOH solution visibly shortened the preform impregnation time.