Temperature Dependence of the Oxygen Solubility in Acrylates and its Effect on the Induction Period in UV Photopolymerization

Abstract

Summary: The influence of temperature on the kinetics of the UV photopolymerization of two diacrylates carried out under air was studied by real‐time FTIR‐ATR spectroscopy. In the temperature range up to 100 °C, the rate of polymerization obeys the Arrhenius law. The induction period was found to decrease with increasing temperature. It was shown that this decay is exclusively due to the decreasing solubility of oxygen in the acrylate. Moreover, from the induction period and the oxygen solubility, quantum yields of the α‐cleavage of some photoinitiators were estimated.Induction period calculated from the solubility of oxygen in TPGDA in comparison with experimental data from RT‐FTIR measurements.magnified imageInduction period calculated from the solubility of oxygen in TPGDA in comparison with experimental data from RT‐FTIR measurements.

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