METHOD OF PRODUCING THERMALLY REGROUPED PBX, THERMALLY REGROUPED PBX AND MEMBRANE CONTAINING THEREOF Russian patent published in 2019 - IPC C08G73/18 C08G73/22 C08G75/32 B01D71/66 B01D71/62 

FIELD: chemistry.

SUBSTANCE: present invention relates to a method of producing thermally regrouped polybenzoxazole, polybenzimidazole or polybenzothiazole (collectively referred to as PBX), to thermally regrouped PBX and membranes containing them. Method of the present invention involves the following steps of the method: obtaining a polyimide or an aromatic polyamide as a precursor polymer in a solution, wherein in each repeating monomer link of precursor polymer aromatic ring is located next to nitrogen atom of imide group or amide group of monomer link, wherein in some or all repeating monomer links the aromatic ring is functionalised with -XR group as a side chain in the ortho position relative to the nitrogen atom, where X = O, N or S, and carrying out thermal treatment to effect thermal rearrangement leading to thermally regrouped polybenzoxazole, polybenzimidazole or polybenzotriazole, wherein R is an allyl group or an allyl-based group, and wherein the treatment temperature used in the heat treatment for the thermal rearrangement is in range of 0 °C to 350 °C.

EFFECT: invention improves separating properties and permeability of membranes made from thermally regrouped PBX.

21 cl, 4 ex, 1 tbl, 20 dwg