High refractive index polymers (HRIPs), especially sulfur-containing HRIPs, play an important role in optical materials; particularly the thermosetting sulfur-containing polyurethane is widely used in optical lenses. To understand the effect of thiol and isocyanate structures on thermosetting polythiourethane properties, a comprehensive study of the basic thermal, optical and mechanical properties of the obtained polythiourethane network structure was conducted, which results indicated that in addition to functionality and the presence of rigid groups affect the glass transition temperature, the conjugation effect and steric hindrance effect in the structure can also cause more changes in the glass transition temperature. All polythiourethane materials formed uniform and densely crosslinked network structures. Due to the introduction of highly polarizable sulfur atoms in 2,3-bis((2-mercaptoethyl)thio)-1-propanethiol (GST) and benzene rings in bis(isocyanatomethyl)benzene (XDI), the resulting polythiourethanes exhibited a high refractive index of 1.6559 (589 nm) and a tensile strength of 95.64 MPa while the Abbe's number was 33.24, fully meeting the lens requirements. The important structure-property relationships of polythiourethane will be helpful for the rational design of HRIPs.

高折射率聚合物（HRIP），尤其是含硫的HRIP，在光学材料中起着重要的作用。特别是热固性含硫聚氨酯广泛用于光学镜片。为了了解硫醇和异氰酸酯结构对热固性聚硫氨基甲酸酯性能的影响，对所得聚硫氨基甲酸酯网络结构的基本热，光学和机械性能进行了全面研究，结果表明除官能度和刚性基团的存在影响玻璃化转变温度，结构中的共轭效应和位阻效应也会引起玻璃化转变温度的更多变化。所有聚硫代氨基甲酸酯材料均形成均匀且致密的交联网络结构。由于在2,3-双（（2-巯基乙基）硫代）-1-丙硫醇（GST）中引入了高度可极化的硫原子，在双（异氰酸根合甲基）苯（XDI）中引入了苯环，因此所得的聚硫代氨基甲酸酯显示出高折射性折射率为1.6559（589 nm），抗拉强度为95.64 MPa，而阿贝数为33.24，完全满足了镜片的要求。聚硫氨酯的重要结构-性质关系将有助于HRIP的合理设计。