Catalyst for making polycarbonate diols for use in polycarbonate urethanes

A polyurethane which is the reaction product of:

• a. a polycarbonate diol having a molecular weight between 500 and 5000 prepared by the reaction of a hydroxy-terminated aliphatic diol with a dialkyl carbonate in the presence of a titanium catalyst, said catalyst being a titanium compound which is substantially free from alkali metal;
• b. an organic diisocyanate;
• and
• c. an organic compound containing at least two isocyanate-reactive hydrogens and having a molecular weight below 250.

A safety glass laminate comprising:

• a. a ply of glass;
• and
• b. laminated to said ply of glass a ply of transparent, energy-absorbing polycarbonate urethane which is the reaction product of
• (1) a polycarbonate diol having a molecular weight between 500 and 5000 prepared by the reaction of a hydroxy-terminated aliphatic diol and a dialkyl carbonate in the presence of a titanium catalyst said catalyst being a titanium compound which is substantially free from alkali metal;
• and
• (2) an organic diisocyanate.

A safety glass laminate comprising:

• a. a ply of glass;
• and
• b. laminated to said ply of glass, a ply of transparent, energy-absorbing polycarbonate urethane which is the reaction product of:
• (1) a polycarbonate diol having a molecular weight between 500 and 5000 prepared by the reaction of a hydroxy-terminated aliphatic diol and a dialkyl carbonate in the presence of a titanium catalyst, said catalyst being a titanium compound which is substantially free from alkali metal;
• (2) an organic diisocyanate;
• and
• (3) an organic compound which contains at least two isocyanate-reactive hydrogens and has a molecular weight less than about 250.