A method of manufacturing a chemical-mechanical polishing (CMP) pad comprising: forming a layer of a polymer resin liquid solution; inducing a phase separation in the layer of polymer solution to produce an interpenetrating polymeric network comprising a continuous polymer-rich phase interspersed with a continuous polymer-depleted phase in which the polymer-depleted phase constitutes 20 to 90% of the combined volume of the phases; solidifying the continuous polymer-rich phase to form a porous polymer sheet; removing at least a portion of the polymer-depleted phase from the porous polymer sheet; and forming a CMP pad therefrom.; The method provides for microporous CMP pads having a porosity and pore size that can be controlled by selecting the concentration polymer resin in the polymer solution, selecting the solvent based on the solubility parameters of the polymer in the solvent polarity of solvent, and selecting the conditions for phase separation.