BLOCK COPOLYMER OF CONJUGATED DIENE AND MONOVINYL AROMATIC HYDROCARBON, HALOGEN-MODIFIED BLOCK COPOLYMER BASED ON IT, METHOD FOR PRODUCING A HALOGEN-MODIFIED BLOCK COPOLYMER, USE OF THE MODIFIED BLOCK COPOLYMER AS A FIRE RETARDANT AND POLYSTYRENE-BASED MATERIAL CONTAINING THE FIRE RETARDANT Russian patent published in 2023 - IPC C08F297/04 C08F8/20 C09K21/08 C08L95/00 

FIELD: halogen-modified butadiene-styrene block copolymers.

SUBSTANCE: invention can be used as flame retardants for polymer compositions based on foaming polystyrene. The following is proposed: a block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon characterized by a weight-average molecular weight (Mw) from 70,000 to 120,000 g/mol, having a bimodal molecular weight distribution, and the content of the low molecular weight fraction ranges from 98.5 to 40 wt.% based on the total the mass of the block copolymer, the content of the high molecular weight fraction ranges from 1.5 to 60 wt.% in terms of the total mass of the block copolymer, and the ratio (X) of the average weight molecular weight of the low molecular weight fraction (Mw1) to the average weight molecular weight of the high molecular weight fraction (Mw2) is from 1:1.1 to 1:10; a halogen-modified proposed block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon; a method for producing the proposed halogen-modified block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon; the use of the proposed halogen-modified block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon as a fire retardant; and a polystyrene-based material containing the proposed halogen-modified block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon.

EFFECT: increased heat resistance and increased compatibility with polystyrene of the resulting halogen-modified block copolymer of a conjugated diene and a monovinyl aromatic hydrocarbon.

41 cl, 8 dwg, 2 tbl, 14 ex