Evaluation of new thiol-acrylic system

Three acrylates and two mercaptans were selected as formulations of thiol-ene photopolymerization system. RT-FT-IR was used to monitor the curing processes of different formulations. Various performances, including shear strengths, hardness and refractive index of different compounds were measured, respectively. The relationship between performances and formulations were discussed. The results showed that: THEIC sample displayed the highest crosslink density; double bond conversion reach 100%; shear strength and shore D hardness also reached highest, showing 7.95 MPa and 58.0, respectively. While, the thiol conversion of THEIC sample was lower than that of DCPDA sample, which exhibited 53.54%. It could be attributed to that fewer double bond of THEIC reacted with thiol than DCPDA. EBDA sample showed the highest refractive index, led by conjugated structure. In addition, the refractive index of PETMP sample was higher than that of TMMP. These indicated that conjugated structure and sulfur content could help to improve refractive index of samples.