Development of Novel Triazine-Based Poly(phenylene sulfide)s with High Refractive Index and Low Birefringence

High-refractive-index (high- n ) polymers with a high optical transparency and low birefringence (Δ n ) have been desired in progressive optoelectronic devices. However, the trade-off between high- n and low-Δ n remains a challenge at present. Here, the development of a novel array of high- n , high-sulfur-containing, highly transparent, colorless poly(phenylene sulfide) (PPS) polymers bearing triazine units in the main chains is reported. Six new triazine monomers T1-T6 with various pendant groups via different linkers (-O- and -NH-) could be prepared for developing PPSs with high- n and low Δ n values. These PPSs ( P1-P6 ) were obtained by the polycondensation of T1-T6 with commercial aromatic dithiol, 4,4'-thiobisbenzenethiol, respectively, which showed very high- n values ( n av : 1.6902-1.7169 at 633 nm), high optical transparency ( T % > 90% @ 400 nm), and low birefringence (Δ n = 0.0015-0.0042). All the PPSs displayed high n ∞ values (1.6340-1.6654), providing valuable information for the development of high- n triazine-based PPS materials for application not only in the visible region but also in the near-infrared region.