PURPOSE: A prepolymer composition having a prolonged pot life and giving an elastomer of a reduced hysteresis loss, prepared by vacuum-distilling a speci fied prepolymer to remove free tolylene diisocyanate and specifying its structure.
CONSTITUTION: A prepolymer composition prepared by vacuum-distilling a prepolymer comprising a polyol and a 2,4-/2,6-tolylene diisocyanate mixture of a 2,6-isomer content of above 1wt% and produced at an NCO/OH equivalent ratio of 1.2W5.0 to remove free tolylene diisocyanate to a content ≤1wt% and containing the isocyanate groups of 2,6-tolylene diisocyanate as isocyanate residues of prepolymer terminals. By reacting and curing this composition as the principal component with a curing agent as another component, the pot life is prolonged and so the workability is improved and a polyurethane elastomer reduced in hysteresis loss and improved in elastic properties can be obtained.
KAMIYAMA MASAYUKI
ASAI SEIJI
| JPS5626858A | 1981-03-16 |
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