Curing and mechanical properties of UV-curable nano-composites

Curing and mechanical properties of UV-curable nano-composites

In this research, TiO2 pigmented and unpigmented epoxy acrylate/SiO2 nanocomposites were prepared and their curing behavior and mechanical properties were evaluated. For this purpose, photo-DSC and DMA analysis were used. The extent of SiO2 content in samples was chosen in the range of 0-3phr. The results showed that the ultimate conversionvalues increased by 14.1% and 17.6% when 1 and 3 phr silica nanoparticles was added to unpigmented formulation, respectively. On the other hand, the final conversion ofTiO2 pigmented formulations increased by 31.7% and 57.1%using 1 and 3phr silica nanoparticlesin the formulations, respectively. These results revealed that the incorporation of silica nanoparicles into pigmented formulations had a more considerable effect comparing to the unpigmented one. The elastic modulus of unpigmented cured films which had 1 and 3 phr silica nanoparticles increased by 21.4% and 23.8%, respectively, in comparison to the neat sample. The effect of silica nanoparticles on the elastic modulus of pigmented cured film was more considerable and it increased by 28% and 52% in comp arison to the neat sample when 1 and 3 phrnano-SiO2 was incorporated in the formulation. The Tg of nanocomposite samples was found to be higher than that for the neat samples. Once again it was more significant for the pigmented formulations.