Core Insights - The development of polysulfide polyurethane and polysulfide ether resins is crucial for producing high-refractive optical materials, with refractive indices starting from 1.59 and reaching up to 1.76 [1][6] - The domestic market for optical materials is currently reliant on imports for high-refractive index resins, highlighting the need for local production to meet the growing demand from a large population of myopic patients in China [6] Group 1: Material Properties and Synthesis - Sulfide polyols play a key role in enhancing the refractive index and toughness of optical resins, with a focus on the design and synthesis of new thiols [1] - The synthesis of polysulfide polyols involves a reaction between mercaptoethanol and epichlorohydrin, which requires careful purification to avoid color and purity issues in the final product [2][3] - The optimization of synthesis parameters for intermediates like 1,3-bis(2-hydroxyethylthio)-2-propanol is essential for improving the purity and color of the final product, 2,3-bis(mercaptoethyl)thiopropanol (BES) [3] Group 2: Purification and Stability - Advanced purification techniques are necessary to remove impurities and color from polysulfide polyols, as traditional methods may not effectively separate the desired products from by-products [2] - Controlling the residual thiourea in the synthesis process is critical for enhancing the storage stability of the final optical materials, preventing discoloration and turbidity during storage [4][5] Group 3: Market Demand and Industry Development - The increasing prevalence of myopia in China, with over 700 million affected individuals, drives the demand for high-refractive index optical materials, necessitating the domestic production of polysulfide polyurethane and polysulfide ether [6] - The upcoming Polyurethane-Polysulfide Industry Chain Conference aims to address the challenges and opportunities in localizing the production of these materials, fostering collaboration among experts and industry representatives [6]