Storage stable mixture of a diisocyanate and the reaction product of a polyester, a glycol and a diisocyanate, and method of making same

Claim 1

IN THE PREPARATION OF AN ELASTOMERIC SUBSTANTIALLY NON-POROUS POLYURETHYTHANE BY A PROCESS WHICH COMPRISES REACTING A POLYMER WITH AN ORGANIC DISOCYANATE AND A GLYCOL TO FORM A STORABLE PRODUCT AND THEN REACTING THIS PRODUCT WITH ADDITIONAL DISOCYANATE, THE METHOD OF MIXING A STORABLE PRODUCT OF IMPROVED STABILITY WHICH COMPRISES MIXING (1) A SUBSTANTIALLY LINEAR POLYESTER SELECTED FROM THE CLASS CONSISTING OF A POLYESTER PREPARED BY ESTERIFICATION OF A DICARBOXYLIC ACID AND AN ALIPHATIC GLYCOL AND A POLYESTER PREPARED BY ESTERIFACATION OF A DICARBOXYLIC ACID, A MAJOR AMOUNT OF AN ALIPHATIC GLYCOL AND A AMOUNT OF A COMPOUND SELECTED FROM THE CLASS CONSISTING OF A DIAMINE AND AN AMINO ALCOHOL, SAID POLYESTER HAVING AN ACID NUMBER OF ABOUT 1 AND AN OH NUMBER OF FROM ABOUT 20 TO ABOUT 80 AND (2) FROM ABOUT 1 PERCENT TO ABOUT 10 PERCENT BY WEIGHT BASED ON THE WEIGHT OF THE POLYESTER OF A GLYCOL HAVING ITS HYDROXYL GROUPS ATTACHED TO AN ORGANIC RADICAL OF LESS THAN 16 CARBON ATOMS, SAID GLYCOL BEING FREE FROM AROMATIC RADICALS AND SELECTED FROM THE GROUP CONSISTING OF ALIPHATIC GLYCOLS AND CYCLOALIPHATIC GLYCOLS, AND THEREAFTER MIXING THE RESULTING MIXTURE UNDER SUBSTANTIALLY ANHYDROUS CONDITIONS WITH (3) AN ORGANIC DISOCYANATE IN AN AMOUNT INSUFFICIENT TO REACT WITH ALL OF THE FUNCTIONAL GROUPS OF THE POLYESTER AND GLYCOL, EFFECTING CHEMICAL REACTION UNDER SUBSTANTIALLY ANHYDROUS CONDITIONS TO FORM A MILLABLE ADDUCT HAVING TERMINAL HYDROXYL GROUPS AND AN HYDROXYL NUMBER OF AT LEAST 5, AND THEREAFTER MIXING THE ADDUCT WITH AN EXCESS OF AN AROMATIC DISOCYANATE.