Price: 10.00
A kinetic study of the UV-curing of waterbased acrylate resins was conducted by means of infrared spectroscopy. Under intense illumination, the crosslinking polymerization occurred in the dried film within less than 1 second. The influence of a number of critical factors on the polymerization rate and cure extent has been investigated, namely the type of photoinitiator, the chemical structure of the acrylate functionalized oligomer and the sample temperature. Coatings obtained from emulsions polymerize faster and more extensively than coatings obtained from dispersions, because of a greater molecular mobility in the soft low-modulus polymer formed. Very hard coatings were produced by UVcuring of dispersion-type acrylate resins, specially when the UV-irradiation was performed at 80°C on the sample emerging from the drying oven. Tg values up to 120°C were reached when such resins were UV-cured at ambient temperature as 1 mm thick plates, because of the large amount of heat released during such ultrafast polymerization.
