Methyl methacrylate rigid contact lenses doped with N-Vinylpyrrolidone and 3-[Tris(trimethylsiloxy)silyl] propyl methacrylate for improved oxygen permeability

Although soft contact lenses can be adapted to fit different people's eyes, their lack of durability and susceptibility to breakage still exist. The effect of N-vinyl-pyrrolidone (NVP) and 3-[Tris(trimethylsiloxy)silyl] propyl methacrylate (TRIS) on the performance of conventional PMMA rigid contact lenses was investigated in this study. Unlike PMMA rigid contact lenses, we used in-situ copolymerization by introducing the hydrophilic NVP and the silicone-containing monomer TRIS into the molecular chain. We utilized the silicone element in the molecular chain of the copolymer, which has an affinity for oxygen, and the five-membered ring of NVP to allow water molecules to enter the poly(MMA-NVP-TRIS) contact lenses, creating dual channels of a water channel and a silicone channel to transport oxygen. The modified PMMA-based materials were under analysis for their structural, optical, mechanical and transparency features, such as light transmittance, oxygen permeability, and equilibrium water content and so on. Moreover, it was found that the introduction of NVP increased the surface wettability and water content of this material and that the introduction of TRIS increased the oxygen transmission value of this material. In addition, the oxygen transmissibility of poly(MMA-NVP-TRIS) contact lens was twice as high as that of soft commercial contact lenses (CCLs) and we used CCLs as a comparison to evaluate other comprehensive performances visually.