Controlled grafting of a well-defined polymer on a porous glass filter by surface-initiated atom transfer radical polymerization

The atom transfer radical polymerization (ATRP) technique using the copper halide/sparteine complexes was applied to the graft polymerization of methy l methacrylate on a porous glass filter on which the initiator, 2-(4-chloro sulfonylphenyl) ethyltrichlorosilane, was immobilized by chemisorption. The graft chains were cleaved from the glass filter by the HF treatment in the presence of a phase transfer catalyst. Gel permeation chromatographic and infrared absorption spectroscopic measurements confirmed that the polymeriz ation carried out in the presence of the free (sacrificing) initiator, p-to luenesulfonyl chloride, afforded a graft layer of well-controlled, low-poly dispersity polymer on the inner surface of the porous glass filter. The num ber-average molecular weight (M-n) of the graft polymer increased with reac tion time, and it was nearly equal to the M-n of the free polymer produced in the solution. The graft density on the inner surface of the porous glass filter was as high as those formed on a silicon wafer and a silica particl e under similar conditions. (C) 2001 Elsevier Science Ltd. All rights reser ved.