Effect of surfactants on the crack resistance of epoxy-rubber materials

Brittle glassy epoxy polymers can be transformed into materials with a high impact strength by dispersion of particles of low-molecular-weight rubbers in them. The effect of surfactants on the crack resistance of an ED-20 epoxy polymer and epoxy-rubber materials based on it were studied. Reverse gas chromatography determined the thermodynamic stability of the components. The surfactant consisted of hydroxylated alkylphenol ether. The experimental method consisted of static loading a two-arm sample with a normal break with a crack before its unstable movement began and finding the values of the critical load causing movement of the crack. Polarity effects of the rubber on crack resistance were also examined. It was found that a surfactant which affects volume properties of an epoxy polymer improves the adhesive interaction between the components of the unstable epoxy-polymer-rubber mixture which increases its crack resistance.