Sulfur-containing polymers are useful in a wide range of optoelectronic applications, although their transparency and refractive indices are challenging to control precisely. Herein, we present a facile strategy for systematically modulating the optical properties of poly(2-methylthio-1,5-phenylene sulfide) (SMePPS) via post-polymerization modification. Initially, the selective side-chain oxidation of SMePPS yielded methyl sulfoxide-containing poly(phenylene sulfide) (PPS), exhibiting higher Abbe numbers, higher transparency, and ultrahigh refractive indices (n_D = 1.75–1.80). Demethylation of SMePPS also yielded thiol-substituted PPS (SHPPS) with an even higher refractive index (n_D = 1.84), owing to the intermolecular hydrogen bonding and the trace cross-linking effect. Furthermore, the film formability/stability of SHPPS was enhanced through copolymerization with methoxy-substituted PPS without comprising the refractive index properties. This facile post-polymerization modification strategy can achieve desirable tuning of optical properties in various sulfur-containing polymers.

中文翻译：

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高折射率甲硫基取代聚苯硫醚的多样化侧链转化

含硫聚合物可用于广泛的光电应用，尽管其透明度和折射率难以精确控制。在此，我们提出了一种通过聚合后改性系统地调节聚（2-甲硫基-1,5-苯硫醚）（SMePPS ）光学性能的简便策略。最初， SMePPS的选择性侧链氧化产生了含甲基亚砜的聚苯硫醚（PPS），具有更高的阿贝数、更高的透明度和超高折射率（n _D = 1.75–1.80）。SMePPS的去甲基化还产生了硫醇取代的 PPS ( SHPPS ) ，由于分子间氢键和微量交联效应，其折射率甚至更高 ( n _{D = 1.84)。此外，通过与甲氧基取代的PPS共聚，} SHPPS的成膜性/稳定性得到增强，且不影响折射率特性。这种简便的聚合后改性策略可以实现各种含硫聚合物光学性能的理想调节。