1,6-Bis-3-(vinyl-3-2-pyrrolidonyl)hexane (BNVP) was synthesized for use as a crosslinker in the photopolymerization of 1-vinyl-2-pyrrolidone (NVP). A model compound, 3-hexyl-1-vinyl-2-pyrrolidone (HNVP), was also synthesized for use as a model comonomer in the kinetic studies of NVP copolymerization. Copolymerizations with NVP and low feed ratios of HNVP indicate that allyl substitution in the 3-position on the pyrrolidone ring does not affect radical reactivity of the monomer. However, the comonomer containing this hexyl side chain acted as an internal plasticizer for the NVP polymers, lowering the T-g and reducing the effect of autoacceleration on the photopolymerization process. The crosslinked polymers exhibited gel-like swelling in water. The crosslinker limited the mobility of the polymer chains early in the polymerization and induced earlier onset of the Tromsdorff effect.