Technological methods for modifying the DER-331 epoxy oligomer have been developed to improve the thermophysical properties of composite materials and protective coatings based on them. The chemical structure of the phthalic anhydride modifier (PA modifier) was investigated by gas chromatography with mass selective detection. This allowed us to reveal the molecular compatibility of the components and, accordingly, their interaction. Based on the research findings, the optimal content of the phthalic anhydride modifier in the reactoplastic matrix with the improved thermophysical properties was determined, which is q = 0.10...0.25 pts. wt. per 100 pts. wt. of the DER-331 oligomer and 10 pts. wt. of the triethylenetetramine (TETA) cold hardener. The modified composites have the following characteristics: Martens heat resistance is T = 360...362 K; thermal coefficient of linear expansion is alpha = (2.33...2.49) x 10-K-5 -(1) in the increment T = 303...323 K temperature range; the glass-transition temperature is Tc = 344...345 K; shrinkage posite structure with the optimal modifier content of q = 0.10...0.25 pts. wt., which enhances the thermo-physical properties of materials.

The research of modifier 3,3-dichloro-4,4-diaminodiphenylmethane (MBOCA) exposure on thermophysical characteristics of composite materials is carried out. In order to analyze the composites' response to the effect of thermal field, the thermal coefficient of linear expansion (CTE) has been calculated. Thermogravimetric (TGA) and differential thermal (DTA) analyses were carried out in order to study thermal destruction and structure formation processes. Maximum temperature values of exothermic effect were found to be dependent on the composite material applied. Shrinkage of the modified matrix, glass transition temperature, and Martens yield temperature were studied. In addition, the polymer fracture topology was analyzed by the optical microscopy. According to the results of DTA and TGA measurements, the optimal temperature ranges for epoxy composites with MBOCA modifier content q = 0.10 wt.% were established. The material with a maximum value of destruction completion temperature T0 = 640.5 K was formed. The minimum value was T0 = 537 K, the difference between minimum and maximum values was ΔT0 = 103 K. This difference indicates substantial effect of modifiers on the initial value of destruction temperature. Exothermic effects were found during the influence of the composite thermal field in the temperature range ΔT from 456 to 770 K. The value of maximum temperature Tmax of exo-effects in a composite with MBOCA modifier content q = 0.50-2.00 wt.%, compared to an unmodified matrix (Tmax = 618 K), lie within the range from 619 to 696 K. The difference between minimum and maximum values composes ΔT = 78 K, which is a validation of substantial positive matrix structure alteration after the modifier admission into the ED-20 epoxy oligomer matrix.

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.

We study the adhesive and physicomechanical properties of composite materials based on the epoxypolyester binders with additions of a methylenediphenyl diisocyanate modifier. It is shown that the matrix with a content of modifier q = 0.25 wt.% is characterized by the highest adhesion and cohesion parameters. The tensile adhesive strength of the epoxy-polyester matrix with improved adhesive properties constitutes σa = 55 MPa, and its residual stresses are σr = 4.1 MPa. The matrix with improved cohesive properties is characterized by the following parameters: its modulus of elasticity in bending E = 3.7 GPa, the fracture stress in bending σst = 57 MPa, and the impact toughness W′ = 8.9 kJ/m2. The fracture surfaces of composite materials are studied by the method of optical microscopy. It is shown that the presence of modifier strongly affects adhesive and cohesive properties of the investigated materials.

It is proved, that for improving the performance characteristics of vehicle parts, including their corrosion resistance and wear resistance, it is advisable to use protective polymeric composite coatings. It is shown that in order to increase the indexes of physical-mechanical and thermophysical properties in the epoxy binder, it is necessary to introduce additives: modifiers, plasticizers, dispersed and fiber fillers. The introduction of dispersed additives into the epoxy binder is actual. It this case, it is effective to use fillers of different dispersity in the complex. The influence of two-component polydispersed filler on the elasticity modulus in flexure of the developed epoxy composite is analyzed. The critical content of a two-component polydispersed filler is found by the method of mathematical planning of an experiment. a mixture of nanodispersed compounds 1 (d = 20 : : : 80 nm) 0:75 : : : 1:0 pts:wt:; a mixture of discrete fibers 1 (l = 0:5 : : : 1:0 mm; d = 18 : : : 25 mu m) -0.2 pts. wt. by the 100 pts. wt. of the epoxy oligomer ED-20. An introduction of the two-component polydispersed filler to the epoxy binder allows significantly to increase the values of the elasticity modulus in flexure of the protective coatings to = 4:8 : : : 5:0hPa. Additionally, the effect of two-component polydispersed filler on the impact resilience of the developed epoxy composite was determined. It is proved that the critical content of a two-component polydisperse filler is: a mixture of nanodispersed compounds 2 (d = 30 : : : 40 nm) 1:00 : : : 1:25 pts:wt., a mixture of discrete fibers 2 (l = 0:5 : : : 1:0 mm;d = 18 : : : 25 mu m) 0:1 : : : 0:2 pts:wt: by the 100 pts. wt. of epoxy ED-20. An introduction of the two-component polydispersed filler to the epoxy binder allows significantly to increase the values of the impact resilience to W' = 10.0... 10.2 kJ/m 2 : The obtained results allow us to create polymeric coating with improved indexes of the physical and mechanical properties in complex.

The effect of Ag2CO3 on the thermophysical properties of epoxy composites was investigated. The thermal linear expansion coefficient of materials that can be used in different temperature ranges has been established. The thermal stability and structural features of materials on increase in temperature were studied by the method of differential thermal analysis and thermogravimetrical analysis. The activation energy of developed polymer composites was calculated. Temperature ranges in which the structural transformations occur, namely, the deformation of epoxy binder macrochains and segments and breakdown of chemical bonds, were also identified by an infrared spectral analysis.