The N,N-diethyl dithiocarbamato group present in a variety of compounds acts as an initiator in the photopolymerization processes. The photolability of this group is due to the cleavage of the C-S bond by UV irradiation. N,N-Diethyl dithiocarbamato-(1,2)-propane diol with a pendent N,N-diethyl dithiocarbamato group was prepared from 3-chloro-(1,2)-propane diol and sodium diethyl dithiocarbamate. A polyurethane macrophotoinitiator was then synthesized by a two-step process, where N,N-diethyl dithiocarbamato-(1,2)-propane diol was used as the chain extender. Other components used included 4,4'-diphenylmethane diisocyanate and poly(propylene glycol) (molecular weight = 1000). The polyurethane thus synthesized had pendent NA-diethyl dithiocarbamato groups. This polyurethane macrophotoinitiator was then used to polymerize methyl methacrylate in a photochemical reactor (Compact-LP-MP 88) at 254 nm, The resulting graft copolymer, poly-urethane-g-poly(methyl methacrylate), was freed from the homopolymer by a standard procedure. The graft copolymer was characterized by Fourier transform infrared spectroscopy, H-1-NMR spectroscopy, thermogravimetric analysis, differential scanning calorimetry, Solution viscometry, and scanning electron microscopy. (C) 2008 Wiley Periodicals, Inc. J Appl Polym Sci 112:64-71, 2009