Photopolymérisation de macromères multifonctionnels—I. Étude Cinétique

Highly crosslinked polymers have been obtained by photopolymerization of multiacrylate macromers under intense u.v. or laser irradiation. The marked inhibitory effect of O₂ was quantitatively evaluated by a kinetic study of these ultra-fast reactions by i.r. spectroscopy. The rate of polmerization (R_p) and the amount of residual unsaturation in the cured polymer were shown to depend primarily on the nature of the macromer chain and on the functionality of the monomer used as diluent. Despite the high rate of initiation, polymerization develops effectively, with large quantum yields: θ_p = 8300 polymerized units per photon absorbed for irradiations in N₂. The linear relationship between R_p and light-intensity strongly suggests a polymerization mechanism based on monomolecular termination.