POLYMERS, POLYMER MEMBRANES AND METHODS OF THEIR PRODUCING Russian patent published in 2017 - IPC C08G73/10 C08G73/18 C08G75/32 B01D71/64 B01D53/22 

FIELD: chemistry.

SUBSTANCE: polymer contains repeating units of the following formulas I-III: formula I; formula II; and formula III, where formula I can be associated with formula II or III, but can not be associated with itself; formula II can be associated with formula I or III, but can not beassociated with itself; and formula III may be associated with formula I or II, or with itself, in which Ar₁ is ; Ar₂ is ; Ar₁' is a divalent group derived from Ar₁; Ar₁" is a trivalent group derived from Ar₁; X and Y are selected from O, S and N-phenyl. The method of producing the above polymer is that thermal treatment of the aromatic polyimide precursor containing a repeating unit of formula IV is carried out: formula IV, in which Ar₁ and Ar₂ have the above meanings; o-FG is selected from the group consisting of -OH and -NH-phenyl. Thermal treatment is carried out by irreversible and intramolecular rearrangement at temperatures of 350°C to 500°C. From the above polymer, a membrane is obtained to separate the gases. The method of separating the liquid components consists in that the separation device comprising the above-mentioned separation membrane is first provided. In the separation device, the feed liquid is provided that contains a mixture of the first fluid and, at least, the second fluid. Then, a product is selected from the separation device, in which the first liquid has a higher purity than in the feed liquid.

EFFECT: invention allows to obtain a polymer with improved mechanical properties, which has an increased free volume and a narrower size distribution of the free volume structure, and to obtain a membrane with a high gas permeability.

9 cl, 5 dwg, 2 tbl, 5 ex