МОДИФІКОВАНА ЕПОКСИДНА МАТРИЦЯ ДЛЯ ЗАХИСТУ ЗАСОБІВ ТРАНСПОРТУ: АДГЕЗІЙНІ ТА ФІЗИКО-МЕХАНІЧНІ ВЛАСТИВОСТІ

Abstract

The significance of application of the polymer composite materials in current technologies has been proven, since they have been demonstrating high performance parameters, offering improved adhesion failure resistance, enhanced mechanical and thermophysical properties which as a consequence enables their application under both ambient and elevated temperatures. The purpose of the current work is to investigate the influence of the phthalimide modifier on the adhesive and physico-mechanical properties of epoxy composite materials and protective coatings based on them. The ED-20 epoxy diane oligomer has been taken as the main component for the binder in the formation of epoxy materials. Polyethylene polyamine hardener has been used for the crosslinking of epoxy compositions. Phthalimide has been taken as a modifier. The molecular formula of the modifier is: C8H5NO2. The molar mass of phthalimide is 147.13 g/mol. It has been proven that with the introduction of the phthalimide modifier in the amount of 2.0 pts.wt. into 100 pts.wt. of ED-20 epoxy oligomer, the material which offers the following properties is being built up: adhesive failure resistance at breaking off - 47.7 MPa, residual stresses - 1.1 MPa. Compared to the parent epoxy matrix, these properties demonstrate an improvement of the adhesive failure resistance at breaking off by 1.9 times, and in addition to the above, the residual stresses are being reduced by 1.3 times. The composite obtained may be reasonably taken in the form of a matrix when building up an adhesive layer for protective coatings. It has been experimentally proven that in order to build up the materials which would offer improved cohesive properties, it is necessary to use a composition of the following makeup: ED-20 epoxy oligomer (100 pts.wt.), polyethylene polyamine hardener (10 pts.wt.), phthalimide modifier (0.25 pts.wt.). Compared to the parent epoxy matrix, the formation of that kind of a material provides an improvement of the following indicators of physical and mechanical properties of composites: bending critical stresses - from 48.0 MPa to 62.1 MPa; impact value - from 7.4 kJ/m2 to 14.7 kJ/m2. Note that the elasticity coefficient of this material is being reduced compared to the parent epoxy matrix from 2.8 GPa to 2.2 GPa. The composite obtained may be reasonably taken in the form of a matrix when building up the surface layer for protective coatings.