Methods for preparing polyurethanes

摘要

The present invention provides methods for preparing polyurethanes from reaction components including: (a) reacting about 1 equivalent of at least one polyisocyanate; and about 0.1 to about 0.5 equivalents of at least one polyol having 2 to 18 carbon atoms to form an isocyanate functional urethane prepolymer; and (b) reacting the isocyanate functional urethane prepolymer, about 0.05 to about 1.0 equivalents of at least one branched polyol having 4 to 18 carbon atoms and at least 3 hydroxyl groups; and up to about 0.9 equivalents of at least one polyol different from the branched polyol and having 2 to 18 carbon atoms, wherein the reaction components are essentially free of polyester polyol and polyether polyol, as well as methods for preparing polyurethanes using a one pot process.