| 摘要 |
FIELD: silicon-containing polymers. SUBSTANCE: composition contains branched polyorganosiloxane with unsaturated hydrocarbon groups, linear methyl- hydrogen-polysiloxane as cross-linking agent, and platinum catalyst in required quantities. In particular, in said branched polyorganosiloxane having average molecular weight from 9000 to 60000, at least 90% of its organic groups are methyl groups, average ratio of the number of diorganosiloxyl units to number of branching sites ranges from 15 to 40, at least one triorganosiloxyl unit and maximally half number of all diorganosiloxyl units are free of unsaturated residues, the rest of triorganosiloxyl units having one unsaturated residue (content of unsaturated residues 0.2-1 mmol/g). Linear methyl-hydrogen- polysiloxane is a polymer in which number of siloxyl units is by one mole larger than above-mentioned ratio of the number of diorganosiloxyl units to number of branching sites and at least half number of bifunctional siloxyl units have hydrogen atoms directly linked to silicon to silicon atoms. The two polysiloxanes are taken in proportion providing ratio of the number of siliconhydrogen groups in methyl-hydrogen-polysiloxane to number of unsaturated hydrocarbon groups of branched polyorganosiloxane from 1.5 to 3.5. EFFECT: enabled full utilization of capacity of modern high-speed coating machines. 5 cl, 1 tbl, 7 ex |
