METHOD OF PRODUCING POLYCARBONATE DIOL, POLYCARBONATE DIOL, METHOD OF PRODUCING POLYURETHANE AND POLYURETHANE

摘要

PROBLEM TO BE SOLVED: To provide a polycarbonate diol which attains a molecular weight in a predetermined range optimal for improvement of productivity by optimizing the reaction rate in producing polyurethane through reaction of polycarbonate diol with an isocyanate compound, gives colorless polyurethane and allows improvement of the tensile strength, elasticity recovery, etc.SOLUTION: A polycarbonate is obtained by polymerizing a dihydroxy compound with a carbonate compound through an ester exchange reaction in the presence of a saccharide and/or its derivative. The amount of the saccharide and/or its derivative is 0.1-80 wt. ppm relative the total amount of the saccharide and/or its derivative and the dihydroxy compound. A polyurethane is obtained by reacting the polycarbonate diol with an isocyanate compound.