Regulation of Properties of Adhesive Compositions Based on Thiirane by Changing the Hardener Content and Introducing Powder Fillers

Abstract

The possibility of regulating adhesive, deformation–strength, and dynamic mechanical properties of adhesive compositions based on diphenylolpropane thioglycidyl ether (thiirane) by changing the content of the hardener and introducing powder fillers has been studied. It is shown that the dependences of adhesive shear strength, tensile and compressive strength, and glass transition temperature on hardener content are extreme. The maximum values of the properties lie in the region of hardener concentrations below the stoichiometric ratio and shift significantly toward lower concentrations as a result of heat treatment of the composites. The reason for this shift is associated with the peculiarities of the chemical interaction of thiiranes with amine hardeners. It is supposed that, in thiirane-based systems with low hardener contents, the polymerization reaction of dithioglycidyl ether makes a significant contribution to the formation of the complex of properties. It is shown that the introduction of powdered fillers makes it possible to increase the strength of thiirane-based composites without reducing the curing rate. This makes it possible to obtain cheaper and more technologically advanced compositions on their basis for the repair and restoration of damaged machine parts and mechanisms without the use of explosion- and fire-hazardous welding and soldering processes.