In this work we present a novel optical polymer system based on polyurethane elastomer components, which combines excellent UV transparency with high thermal stability, good hardness, high surface tension and long pot life. The material looks very promising for encapsulation and microlensing applications for chip-on-board (CoB) light-emitting diodes (LED). The extinction coefficient k, refractive index n, and bandgap parameters were derived from transmission and reflection measurements in a wavelength range of 200-890 nm. Thermogravimetry and differential scanning calorimetry were used to provide glass transition and degradation temperatures. The surface tension was determined by means of contact angle measurements. As proof of concept, a commercial InGaN-CoB-LED is used to demonstrate the suitability of the new material for the production of microlenses.

中文翻译：

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用于板上芯片 LED 微透镜的新型紫外线透明 2 组分聚氨酯树脂

在这项工作中，我们提出了一种基于聚氨酯弹性体组分的新型光学聚合物系统，它结合了优异的紫外线透明度、高热稳定性、良好的硬度、高表面张力和长适用期。该材料对于板载芯片 (CoB) 发光二极管 (LED) 的封装和微透镜应用看起来非常有前景。消光系数 k、折射率 n 和带隙参数来自 200-890 nm 波长范围内的透射和反射测量。使用热重法和差示扫描量热法来提供玻璃化转变温度和降解温度。表面张力通过接触角测量来确定。作为概念证明，