| Abstract
| - Laser vibrational overtone initiated polymerization of ethylene glycol dimethacrylate(EGDMA) has been demonstrated using two initiators, benzoyl peroxide (BP) and 2,2‘-(azobis)isobutyronitrile (AIBN). Excitation of the initiator occurs through absorption of a single photon by thefifth CH stretching vibrational overtone transition at 604 nm (16 556 cm-1) for BP and 628 nm (15 924cm-1) for AIBN. This vibrational excitation creates radicals that initiate radical chain polymerization.Monomer conversion was followed quantitatively by monitoring the intensity change of the vinylcombination band at 6169 cm-1 in the first overtone spectrum of EGDMA. Considering the concentration,the molar extinction coefficient, and laser power, AIBN was a factor of 3.2 more efficient than BP forvibrational overtone polymerization. In both cases, the rate of polymerization depends on the excitationwavelength. The influence of the initiator concentration and the photolysis duration is also presented.
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