A process for producing a microporous oil sorbent polymer comprising the steps of: dissolving a polyunsaturated monomer in a silicone organic solvent to provide a monomer mixture containing more than 90% by weight polyunsaturated monomer; polymerizing said monomers by precipitation polymerization, under an inert atmosphere to precipitate microporous, micro-particles in the form of micro-particles, agglomerates and aggregates having a bulk density of about 0.02 gm/cm.sup.3 to about 0.01 gm/cm.sup.3 and capable of adsorbing at least about 20% by weight organic materials based on the total weight of polymer plus adsorbed organic material.