| abstract |
Polyurethane comprising the reaction product of: a) a prepolymer prepared by reacting a stoichiometric excess of an aliphatic polyisocyanate with a primary amine-terminated polyether with an amine functionality of about 2 and an equivalent average amino weight of 1,000 to 1,250 essentially free of any other polyether, and in which the free NCO content of the resulting prepolymer is> 18% by weight; b) a polyol selected from the group consisting of (a) a polyol triol polyester with a molecular weight between 540 and 900, (b) a polyether glycol with a molecular weight between 650 and 2,000, and (c) a polyester polyol diol with a molecular weight of up to 2,000; and a curing agent having isocyanate reactive groups, a functionality of 2 to 3 and a molecular weight of <400 selected from the group consisting of (a) dianhydrohexitol; (b) aromatic diamines; (c) cyclohexanedimethanol; and (d) diols containing an aromatic ring. |