FIELD: polymers.
SUBSTANCE: invention relates to an initiating system based on a Brønsted-Lowry acid for cationic polymerisation of an ethylene-unsaturated monomer, wherein said initiating system based on a Brønsted-Lowry acid comprises an initiator with the structure by the formula (I) in an anhydrous polymerisation medium, wherein: M constitutes tantalum (Ta), vanadium (V), or niobium (Nb); R1, R2, R3 and R4 are the same or different and independently constitute H, F, Cl, Br, I, C1-C4-alkyl or phenyl, provided that not all of R1, R2, R3 and R4 on one benzene ring are H; L constitutes an alkyl ether or a cycloalkenyl ether, coordinated with H+; and x equals 2. The invention also relates to a method for producing a polymer using the described initiating system and to a compound by the formula (I).
(I)
EFFECT: production of initiating systems for cationic polymerisation capable of producing a polymer with a sufficiently high molecular weight at higher temperatures.
13 cl, 1 dwg, 7 tbl, 36 ex
