Preparation of photocurable resin. The soft photocurable resin is prepared by mixing BA, BDDA, and BAPOs at the ratios described in Table . Avobenzone was added into the mixture at 0.1 wt.% of total resin as a UV absorber to improve the printing quality by reducing the scattering of light. Afterward, the mixture was bubbled with nitrogen for 30 min to remove oxygen under vigorous stirring. The resin containing sticky monomers is prepared by mixing BA, EAEA, BDDA, and BAPOs at the ratios listed in Table . Again, avobenzone was added at 0.1wt.% of total resin and the mixture bubbled with nitrogen for 30 min to remove oxygen under vigorous stirring.