Polymerization of vinylpyridine

Small polymer particles of polyvinylpyridine of 50 to 2,000 microns diameter having small particles of Ziegler-catalyzed polymer embedded therein, said polymer particles of polyvinylpyridine being produced by the process which comprises polymerizing vinylpyridine in aqueous suspension in the presence of solid particles having diameters in the range 50-600 microns of Ziegler-catalyzed polystyrene or polyolefin of low molecular weight olefins, said polyolefin being derived from 1-olefins having up to about 6 carbon atoms each, wherein the weight ratio of polystyrene or polyolefin particle:vinylpyridine is in the range of about 1.5:1 to about 100:1, the suspension polymerization being carried out in the presence of a water-soluble free radical initiating catalyst.