Catalyst initiated prepolymer systems

A process for manufacturing a polyurethane prepolymer adhesive under room temperature conditions comprising the steps of:

• (a) introducing a predetermined amount of at least one polyol reactant into a reaction vessel;
• (b) mixing a predetermined amount of least one isocyanate reactant into the reaction vessel to give a uniform resin mixture sufficient to give an excess active isocyanate content in the polyurethane prepolymer adhesive of approximately 5% to 20% by weight;
• (c) adding a predetermined amount of catalyst to initiate reaction of the reactants in the reaction vessel, with vigorous stirring to give a uniform mixture, said predetermined amount of catalyst being sufficient to allow the reaction to substantially reach completion within 2 to 8 hours;
• (d) isolating the mixed contents in the reaction vessel from ambient conditions to prevent contamination of the contents by ambient moisture;
• and
• (e) mixing the reactants during the reaction in the reaction vessel until the reaction substantially subsides, whereby the polyurethane prepolymer adhesive is formed.