Kinetics of growth and level of residual stresses during curing of epoxy oligomers with active thinners

Abstract

The paper presents the results of a study of the kinetics and level of residual stresses during the curing of systems based on ED-20 epoxy oligomer with amine curing agent (TETA) and active diluents (AD) having different nature, structure and characteristics (laproxides and laprolate).The effect of the structure, AD content, and curing temperature on the kinetics and level of residual stresses in the ED-20 + TETA + AD systems is shown.It has been established that the most effective AD for reducing residual stresses in the ED-20 + TETA systems are laproxides of grades E-181, 703 and laprolat 301 at a content of 0.15-0.20 vol.Optimal compositions of binders based on epoxy oligomers with active diluents with low level of residual stresses (no more than ~2 MPa), shrinkage of ~3%, initial viscosity of ~0.2 Pa·s at curing temperature of up to 60°C are proposed, which guarantees high-quality impregnation of fibrous fillers and high level having physical and mechanical characteristics of reinforced plastics.