In this work, PPSUs with different molecular weights were synthesized for the development of highly permeable ultrafiltration hollow fiber membranes for the first time. The MW of the synthesized polymers was controlled by varying the monomers molar ratio within 1:1–1.15 under the same synthesis conditions. Based on the study of the rheological properties of polymer solutions, a high molecular weight PPSU (MW 102,000 g/mol) was chosen for the formation of hollow fiber membranes. The addition of PEG400 to the spinning solution led to an increase in viscosity, which makes it possible to work in the region of lower PPSU concentrations (18–20 wt. %) and to form membranes with a less dense porous structure. With the addition of PEG400 to the spinning solution, the membrane permeance increased sharply by more than two orders of magnitude (from 0.2 to 96 L/m2 h bar). At the same time, the membranes had high rejection coefficients (99.9%) of Blue Dextran model filtered substance (MW = 69,000 g/mol).

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Copolymers based on 4,4′-dihydroxydiphenyl, phenolphthalein and 4,4′-dichlorodiphenyl sulfone were synthesized by the method of high temperature polycondensation. The structure of the synthesized copolymers was confirmed by IR spectroscopy. Their physical, mechanical and thermal properties were investigated. It is shown that increases in the content of carded fragments lead to higher glass transition temperatures and heat resistance of the copolymers, as well as higher elastic and strength properties.

Polyethers are of great interest for various industries due to a complex of valuable properties, such as heat resistance, fire resistance, high strength, etc. Carded polymers occupy a special place among polymers with increased heat resistance, containing in the main polymer chain at least one element that is part of the lateral cyclic grouping. The presence of such fragments increases the glass transition temperature and heat resistance, which allows the copolymers to be operated at higher temperatures without changing the physico-mechanical parameters. For crystalline polymers, the presence of cardo fragments leads to better solubility in organic solvents. One of the promising ways of synthesizing heat-resistant polymeric materials is based on the use of aromatic compounds such as 3,3-bis (4'-hydroxyphenyl) phthalide, 3-chloro-3- (diphenyloxyd-4'-yl) phthalide, 3- chloro-3- (diphenylsulfide-4'-yl) phthalide, 9,9-bis (4'-hydroxyphenyl) fluorene, 9,9-bis (4'-hydroxyphenyl) anthrone-10, 2-phenyl-3,3- Bis (4'-hydroxyphenyl) phthalimidine and the like. At present, the worldwide problem of the release of toxic waste into the environment is aggravated, which causes irreversible climatic changes. To solve this problem, it was proposed to develop solid fuel cells based on polymeric proton-exchange membranes. Thus, polymer membranes must satisfy a number of requirements: to provide minimal ohmic losses, to possess considerable proton conductivity, mechanical strength, thermal stability and to have limited solubility in organic solvents. Polymer membranes with carded fragments in the main chain satisfy all the requirements. In the presented review features of synthesis and properties of copolymers on the basis of polysulfones, polyether ketones, polyetherimides with carded fragments are considered.Forcitation:Shakhmurzova K.T., Kurdanova Zh.I., Zhansitov A.A., Baiykaziev A.E., Khashirova S.Yu., Pakhomov S.I., Ligidov M.Kh.Synthesis and properties of aromatic polyesters whith carded fragments. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 6. P. 28-39.

Polyphenylene sulfide is a semicrystalline engineering thermoplastic, in the world market of superconstructive materials is presented in two modifications: the first is a cross-linked material, the second is a linear polymer with a highly ordered supramolecular structure.Polyphenylene sulfides, synthesized according to the classical procedure in N-methyl-2-pyrrolidone, are characterized by low molecular weight characteristics due to the occurrence of side reactions. The main yield of the target product does not exceed 45%, even with an increase in the synthesis time of up to 120 hours.Polymers with higher viscosity characteristics can be obtained by heat treatment of synthesized polyphenylene sulfide at 240-260 °С. Copolymers with new monomeric fragments, such as sulfonic, ketone, amide, imide, etc., have been synthesized, which lead to amorphous polymers. The copolymers obtained are well soluble at room temperature and have a higher yield and a molecular weight. The introduction of cyclic groups into the macromolecule of polyphenylene sulfide results in an increase in heat resistance (500 °C) and solubility. Over the past 10-15 years, special attention has been paid to the synthesis of macrocyclic oligomers, which are used subsequently for the preparation of high molecular copolymers by a ring-opening polymerization reaction. This technique allows to obtain polymers in a short time and without the formation of by-products.During the synthesis of copolymers, extensive knowledge of the effect of the chemical structure on the performance properties of materials was obtained, and new methods were developed that reduced the possibility of percolation reactions. Thus, the synthesis of new polyheteroarylenes becomes topical, the review reflects the results of research over the past few years on the development on their basis of materials with unique valuable properties.