Quantitative Assessment of the Kinetics of Damage Accumulation in the Polymer Matrix Structure Under Full-Scale Climatic Factors and Tensile Loads

Постановка задачи. Изучено изменение упруго-прочностных показателей и кинетики накопления повреждений в эпоксидных полимерах под действием растягивающих нагрузок в контрольном состоянии и после натурного климатического воздействия в течение одного календарного года. Расчет кинетики накопления повреждений осуществлялся на основе авторской методики, основанной на использовании методов фрактального анализа кривых деформирования образцов полимерных материалов при растяжении. Результаты. Предложен удельный показатель θ, позволяющий количественно оценивать суммарное число повреждений на единицу прочности, накопление которого приводит к разрушению полимеров. Получены аппроксимирующие зависимости, описывающие взаимосвязь между удельным показателем θ и пределом прочности эпоксидных полимеров при растяжении. Выводы. Установлено, что наибольшей стабильностью свойств под действием натурного климатического воздействия обладает полимер на основе эпоксидной смолы «Этал-247». Statement of the problem. In the current study we look at the change in the elastic-strength performance and kinetics of damage accumulation in epoxy polymers under tensile loads in the control state and after full-scale climatic exposure during one calendar year were studied. Damage accumulation kinetics was calculated based on the author's method using methods of fractal analysis of deformation curves for polymer materials samples under tension. Results. We proposed specific index θ to quantify the total number of damages per unit of strength where its accumulation leads to the destruction of polymers. The dependences have been obtained that describe the relationship between specific index θ and tensile strength of epoxy polymers. Consclusion. The study has shown that the Etal-247 epoxy resin-based polymer cured with Etal-1440 amine hardener has the most stable properties under the full-scale climatic exposure.

MODIFICATION OF EPOXIDIAN RESIN ED-20 WITH ALUMINUM PHOSPHATE

The modifying effect of aluminum phosphate (PA) on epoxy polymers has been studied. It was found that the introduction into the composition of 1.10 - 3.85 mass. including aluminum phosphate makes it possible to obtain highly modular (2.3 - 3.1 GPa) self-extinguishing polymer composites.

Epoxy Sulfur Containing Olygomers for Fire-Resistant Compounds Based on 2,2di-(4-Oxyphenil)Sulfone

The article presents information on the synthesis of epoxy oligomers based on 2,2-di-(4-hydroxyphenyl) sulfone (DODPS) and hexachloroethane (HCE). We showed the results of a study of the adhesive properties and fire resistance of epoxy polymers. The synthesized sulfur-containing epoxy oligomers have a reasonably low viscosity and high fire resistance. Casting compounds obtained on their basis have improved performance characteristics.

CURING OF DIGLYCIDAL ESTERS OF BISPHENOLS WITH AMINE HARDENERS

The effect of hardeners on the properties of cured epoxy polymers is studied. For the purpose of synthesis of polymers with increased thermal properties. Theglycide esters of polycyclic bisphenols synthesized by us were used as a diol component. Since the thermal and heat resistance of polymers, in addition to the chemical structure of bisphenols, also depend on the structure of the hardener used, amine hardeners of different chemical structure are used to improve the thermal parameters of polymers, both heat resistance and heat resistance. The influence of the chemical structure of these hardeners on the properties of epoxy polymers is studied. Cured epoxy polymers are characterized by high heat resistance. High heat resistance results are obtained by 4,4′-diaminodiphenylsulfone, benzidine, 4,4′-diaminodiphenyloxide and other aromatic diamines. Polymers obtained by curing with these hardeners are deformed in the temperature range of 220-245°C. The use of the above hardeners gives high results in terms of heat resistance. In all cases, the polymers obtained on the basis of these hardeners decrease in weight by 10% in the temperature range of 340-400°C.