Clearcoats based on maleimide/vinyl ether combinations - investigation into their properties and curing behaviour

UV curable maleimide/vinyl ether blends were discussed in literature during the last years. Results of
basic research were published which mainly contained RTIR spectroscopy, differential photocalorimetry, and the mechanism of radical formation. Partially, these results indicated high reactivity and low sensitivity to oxygen inhibition. Therefore, UV curable clearcoats containing maleimides and vinyl ethers were formulated and UV cured in air atmosphere; In principle, it was possible to 'use equimolar maleimide/vinyl ether blends as photoinitiators for acrylates. However, their efficiency was inferior compared to commercial a cleavage photoinitiators. On the other hand, formulations based on certain maleimides and vinyl ether functional resins or/and reactive thinners could be cured without additional photoinitiators. The possibilities and limitations found are discussed.