| 摘要 |
FIELD: chemistry.SUBSTANCE: present invention relates to a method of producing thermoplastic polyurethane, which can be used as binder for composite materials. The present method is realised by reacting a hydroxyl-containing oligoester with excess diphenylmethane diisocyanate, followed by addition of a mixture of polyols until isocyanate groups disappear; the hydroxyl-containing oligoester used is polyethylene adipate diol with molecular weight of 2000; the mixture of polyols used is a mixture of polydiethylene adipate diol with molecular weight of 800 and low molecular weight diol, wherein at the first synthesis step, a pseudo-prepolymer is obtained with molar ratio of polyethylene adipate diol with molecular weight of 2000 to 4,4'-diphenylmethane diisocyanate of 1:3, and the composition of the mixture of polyols used at the second synthesis step corresponds to molar ratio of low molecular weight diol: polydiethylene adipate diol with molecular weight of 800 ranging from 0.8:0.2 to 0.9:0.1, with overall molar ratio of isocyanate groups to hydroxyl groups equal to 0.95-0.98.EFFECT: high flow melt index of thermoplastic polyurethanes with maximum preservation of strength properties for producing binder materials for composite materials that are processed at low temperatures (not higher than 120°C).2 cl, 1 tbl, 15 ex |
