A new method for obtaining porous and porous fiber polymers is presented. This method is based on using gel‐type technology (without previously preparing polymer solutions) for crystallizable polymers, preparing polyethylenes, and including polyethylenes of very high molecular mass and isotactic polypropylene. The method consists in swelling crystalline polymer films at elevated temperatures in a proper solvent with subsequent precipitation with a non‐solvent at different conditions. In this case, simultaneous or consecutive processes of phase separation of amorphous or/and crystalline type occurs; stretching the sample can also accompany this process. Complete phase diagrams of two‐ and three‐component systems (polymer‐solvent and polymer‐solvent precipitator) were constructed. Temperature‐concentration boundaries of amorphous separartion (binodal) and crystallization (liquidus) are reported for the system polyethyleneo‐xylenedimethyl formamide. Phase transitions of both types influence characteristics of the resultant porous structure. They were prepared by simultaneous (precipitation of a gel by dimethyl formamide at 25°C) or consecutive (precipitation with a hot non‐solvent at 138°C and following cooling) phase separation. Studied were the effect of experimental conditions (temperature, times for solvation and precipitation, polymer molecular mass, the thermodynamic quality of solvents and parameters of film stretching) on peculiarities of the structure and quantitative characteristics of final porous and fiber‐porous polyolefins. It has been demonstrated that the method proposed allows us to obtain a crystalline and highly porous polymer with open poros, a bimodal size distribution and with a highly developed inner surface. Further high strength and small shrinkage are characteristic of the fiber‐porous materials. The method under discussion appears to be universal, it does not require a preliminary preparation of polymer solutions and can be realized within a general technology of polymer films and sheet processing. Highly porous polymers obtained by this technology, primarily based on polyethylenes of very high molecular mass, can be used as neutral supports for multi‐functional membranes, polymeric covers, frame systems for implants and other applications.

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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.

The results of sedimentological core analysis of the Achimov Formation (Upper Valanginian, Lower Cretaceous) confirm that it was formed by higher efficiency systems of submarine fans in (relatively) deep marine basin. Lithofacies models of Ach5-6 were generated, well correlation was performed based on the comprehensive analysis of core, well logging and seismic data. Distributary channels and proximal parts of depositional lobes are characterized by the best reservoir properties.