Two-component polyurethane adhesive

A low viscosity two component filled polyurethane adhesive having a urethane content of from 7 to 20 percent, based on the weight of nonfilled polyurethane polymer, comprising

• (a) a low viscosity isocyanate component in a quantity sufficient to provide an isocyanate index of about 100 to 150 comprising an organic polyisocyanate wherein up to 10 equivalent percent of the isocyanate groups of said organic polyisocyanate have been modified by reaction with one or more isocyanate-reactive compounds;
• and
• (b) a low viscosity curative component comprising
• (i) 5 to 50 equivalent percent, based on the total equivalents of amino and hydroxyl groups of components (b)(i) and (b)(ii), of a mixture of
• (A) a polyoxypropylene polyoxyethylene trio having an equivalent weight greater than 1000 and
• (B) an amine terminated polyether prepared by reacting polyoxypropylene polyoxyethylene triol having an equivalent weight greater than 500 with an excess of toluene diisocyanate to form an isocyanate terminated prepolymer and hydrolyzing said isocyanate terminated prepolymer to form the amine terminated polyether
• (ii) 50 to 95 equivalent percent, based on the total equivalents of the amino and hydroxyl groups of components (b)(i) and (b)(ii) of one or more chain extenders and/or crosslinkers having a molecular weight in the range of 32 to 399, wherein (b)(ii) is characterized in that it contains at least one chain extender which comprises from 50 to 100 percent of the isocyanate reactive equivalents of component (b)(ii) and
• (iii) one or more isocyanate reactive diamines or triamines having a molecular weight in the range of 62 to 400 is a quantity sufficient to produce resistance to flow when components (a) and (b) are mixed;
• wherein at least one of the components (a) or (b) contains at least one filler in a quantity of from about 10 to 40 about percent by weight based on the total quantity of the filled polyurethane adhesive.