|
ИСТИНА |
Войти в систему Регистрация |
Интеллектуальная Система Тематического Исследования НАукометрических данных |
||
Targeted Synthesis of Thermo- and Heat-Resistant PolyaryleneEther Ketones with a Complex of Valuable Functional Propertiesстатья
Дата последнего поиска статьи во внешних источниках: 24 июля 2024 г.
- Авторы: Shaposhnikova V.V., Salazkin S.N.
- Журнал: Russian Journal of General Chemistry
- Том: 94
- Год издания: 2024
- Издательство: Maik Nauka/Interperiodica Publishing
- Местоположение издательства: Russian Federation
- Первая страница: 1564
- Последняя страница: 1568
- Оригинальные версии: НАПРАВЛЕННЫЙ СИНТЕЗ ТЕРМО- И ТЕПЛОСТОЙКИХ ПОЛИАРИЛЕНЭФИРКЕТОНОВ, ОБЛАДАЮЩИХ КОМПЛЕКСОМ ЦЕННЫХ ФУНКЦИОНАЛЬНЫХ СВОЙСТВ
- DOI: 10.1134/S1070363224060380
- Аннотация: In order to obtain polyarylene ether ketones with a set of specified functional properties (high thermal and heat resistance, mechanical properties), a study was made of the regularities of polycondensation proceeding according to the mechanism of the reaction of nucleophilic substitution of an activated halogen in an aryl dihalide upon the interaction of 4,4′-difluorobenzophenone with dipotassium diphenolates of bisphenols in N,N-dimethylacetamide. The influence of the duration of polycondensation and the concentration of the reaction mixture on the molecular weight of homo- and copolyarylene ether ketones was studied under the conditions of: 1) equimolar and 2) non-equimolar ratio of monomers (excess of bisphenols) and blocking of terminal phenolic groups with a monofunctional reagent - 4-fluorobenzophenone. In the case of copolymer polyarylene ether ketones, it has been established that the concentration of the reaction system has a significant effect on the growth rate of the molecular weight of the synthesized polymers under conditions of an equimolar ratio of monomers—a higher concentration of the reaction mixture C = 1 mol/L compared to C = 0.5 mol/L provides more high rate of molecular weight growth. Homo- and copolymers with reduced viscosity up to 2,4 dL/g (solution concentration 0.5 g/dL, chloroform) were obtained. The possibility of effective regulation of the molecular weight of homo- and copolymers under conditions of non-equimolar ratio of monomers in the range of reduced viscosity from 0.3 to 0.75 dL/g is shown. The revealed regularities in the synthesis of polyarylene ether ketones have opened up opportunities for purposeful control of the synthesis conditions, structure, and properties of polymers. Depending on the molecular weight and the presence of a side cyclic phthalide group in the main chain, the synthesized homo- and copolymers have an initial softening temperature of 155–230°C, and an initial decomposition temperature in air of more than 450°C. PAEK form strong transparent films (depending on the molecular weight values, the tensile strength for homo-PAEK is 80–105 MPa, for co-PAEK- 70–90 MPa, the modulus of high elasticity is 2×103 MPa). The resulting polymers have a complex of valuable functional properties and are promising for obtaining materials that can work under extreme conditions.
- Добавил в систему: Шапошникова Вера Владимировна