Method of making polyurethane foam

A method of reaction injection molding a polyurethane foam, comprising:

• recirculating a polyol mixture in a first partially evacuated recirculation loop,
• wherein the polyol mixture comprises from about 0.5% to about 4% by weight of water;
• recirculating an isocyanate mixture in a second partially evacuated recirculation loop;
• impingement mixing a portion of the polyol mixture with a portion of the isocyanate mixture to form a reaction mixture;
• injecting the reaction mixture into a mold;
• and,
• allowing the reaction mixture to react to form a polyurethane foam.