Apparatus for forming a porous reaction injection molded chemical mechanical polishing pad

The present invention provides an apparatus for forming a chemical mechanical polishing pad, comprising a tank with polymeric materials, a storage silo with microspheres, a isocyanate storage tank with isocyanates and a premix prep tank for forming a pre-mixture of the polymeric materials and the microspheres. The invention further provides a premix run tank for storing the pre-mixture, a mixer for forming a mixture of the pre-mixture and the isocyanates, a closed mold for reaction-injection molding the mixture and a vacuum for degassing at least one of the tank, isocyanate storage tank or the mold.