Study of thermal effects in polymer coatings with increasing temperature

The change of linear deformations of the developed epoxy composites under the influence of a thermal field is investigated. It is established that nanocomposites are characterized by different rates of relaxation processes, which makes it possible to choose nanocomposites or coatings based on them with the required thermal coefficient of linear expansion for protection of parts of transport equipment, in particular, ship equipment against external influences. It was found that the optimal content of nanodispersed fullerene-carbon black mixture in the reaction plastic matrix is q = 0.050 pph per 100 pph of epoxy oligomer ED-20 and 10 pph of polyethylenepolyamine (PEPA) hardener. The obtained epoxy composites have the following characteristics: thermal coefficient of linear expansion is –α = (5.61...5.79) × 10-5 K-1 in the temperature range ΔT = 303...323 K; the glass-transition temperature is Tc = 338...343 K; shrinkage up to 1%. Using thermogravimetric analysis (TGA) and differential thermal analysis (DTA) methods, the operating temperature range of the developed composite materials without changing their properties was determined to be 273-555 K.