The interest for Polymer Photochemistry has been growing in the last decades as a consequence not only of the great number of new applications as well as due to the repercussion of economical, technical and ecological characters. The photopolymerization - photocuring processes have received special attention due to the countless and important applications in the area of Materials. The kinetics of these processes needs fast and precise analytic methods to be evaluated. Among the conventional analytic methods, the most used are gravimetry and the determination of macroscopic properties, as resistance to traction, deformation and hardness. However, for a better insight in the reactions it is convenient to use more advanced analytic methods, in order to study the photopolymerization kinetics in real time. Dilatometry, Raman spectroscopy, calorimetry, and real time Fourier transform infrared spectroscopy are some of the techniques that have been used. Activity in the field of photopolymerization continues to expand in many areas and recently, the interest in photoinitiation systems involving the initiation of free-radical polymerization with visible light irradiation has been retaken. Additionally, studies on cationic photopolymerization induced by visible light started again to be studied because of the large variety of monomers that can be photopolymerized by via cation initiation, but not by free radicals, such as oxiranes and vinyl ethers.
Cationic photopolymerization; free-radical photopolymerization; dilatometry; calorimetry; gravimetry; Fourier transform infrared spectroscopy
