Water absorption by multifunctional protective epoxy composites

Moscow State University of Civil Engineering, Yaroslavskoe shosse, 26, Moscow, 129337, Russia

^* Corresponding author: smirnov@nocnt.ru

Abstract

Currently, thermoset-based polymer matrix composites are widely used in many areas of construction industry. Such composites demonstrate high compressive and flexural strength and are often characterized by high chemical stability under severe environmental conditions. One of the new promising areas of application of thermoset-based polymer matrix composites is the intumescent protective coating for metals; in normal conditions, such coatings can prevent the corrosion of metal constructions; during fire, expanded layer can prolong the time before critical failure. Water absorption is one of the primary characteristics of corrosion-protective materials; however, till now, there is only limited information about water absorption of multifunctional protective thermoset-based polymer matrix composites for intumescent coatings. In the present work, asymptotic values of water absorption of epoxy composites with polysiloxanes and fluorine-chlorine liquids are examined. The boundaries of control variables, within which the materials with required properties can be made, are determined. Silica, intercalated (expandable) graphite, and asbestos are used as fillers. Experiments were carried out in accordance with central composite experimental designs for full second-order regression models. It is shown that some admixtures can lead to notable decrease of water absorption.