N,N-dimethylacrylamide (DMAA) was graft copolymerized on poly[(trimethylsilyl) propyne] (PTMSP) by single electron reduction of PTMSP with potassium naphthalenide (K-Naph), followed by anion polymerization of DMAA from the carbanion formed in the reduction. A hard and practically non-water-swelling PTMSP-gr-poly(DMAA) was obtained under the conditions using controlled amount of K-Naph and DMAA. The graft copolymer was characterized with regard to structure, number-averaged molecular weight, and the amount of grafting poly(DMAA) determined by the relative absorbance of the IR absorption band assigned to the C=O and SiC-H functionalities (A(C=O)/A(SiC-H)) The oxygen permeability and water contact angle (theta) of the graft, copolymer were evaluated while varying the amount of grafting poly(DMAA). The graft copolymer proved to be highly oxygen permeable (165 Barrers) and hydrophilic (theta = 27 degrees). Its transparency was also elucidated with UV-vis spectra. This graft copolymer was proposed as a promising candidate for use as a hard contact lensmaterial.