Synthesis and properties of UV-curable polyurethane acrylates containing fluorinated acrylic monomer/vinyltrimethoxysilane

摘要

A series of UV-curable polyurethane acrylates containing fluorinated acrylic monomer (heptadecafluorodecyl methacrylate, PFA, 6 wt%)/vinyltrimethoxysilane (VTMS, 0-9 wt%) [FPUA6/0, FPUA6/3, FPUA6/6 and FPUA6/9, where the numbers indicate the wt% of PFA/VTMS] were synthesized from a reactive urethane oligomer (40 wt%) and diluents (60 wt%). This study examined the effect of bulky VTMS (0-9 wt%)/bulky IBOA (34-25 wt%) weight ratio on the properties of the UV-curable polyurethane acrylates for transparent anti-fouling coating materials. In the wavelength range of 400-800 nm, the transmittance % of the FPUA film samples increased markedly up to nearly 100 % with increase in the VTMS content up to 9 wt%. As the VTMS content increased, the storage modulus/tensile modulus/hardness of the UV-cured film samples increased significantly and the tensile strength/glass transition temperature increased a little; however, the elongation at break decreased significantly. XPS showed that the film-air surface of the UV-cured polyurethane acrylate film had a higher fluorine content than the film-dish interface indicating the gradient concentration of fluorine in the structure of the film from the film-air surface to the film-glass interface. As the VTMS content increased from 0 to 9 wt%, the surface tension of the UV-cured urethane acrylate films decreased from 17.2 to 15.9 mN/m, whereas the water/methylene iodide contact angles of the film-air surface increased significantly from 107.9/80.9A degrees to 114.2.9/84.2A degrees. These results suggest that the UV-curable polyurethane acrylate containing 9 wt% of VTMS has strong potential as a coating material for transparent antifouling applications.