Hu Yunfeng, Kowalski Benjamin A, Mavila Sudheendran, Podgórski Maciej, Sinha Jasmine, Sullivan Amy C, McLeod Robert R, Bowman Christopher N
Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, United States.
Department of Chemical and Biological Engineering, University of Colorado Boulder, Boulder, Colorado 80303, United States.
ACS Appl Mater Interfaces. 2020 Sep 30;12(39):44103-44109. doi: 10.1021/acsami.0c08872. Epub 2020 Sep 16.
A high-performance holographic recording medium was developed based on a unique combination of photoinitiated thiol-ene click chemistry and functional, linear polymers used as binders. Allyl reactive sites were incorporated along the backbone of the linear polymer binder to enable facile film casting and to facilitate cross-linking by photopolymerization of the thiol-ene monomers that also serve as the writing monomers in this distinctive approach to holographic materials. The allyl content and the ratio of the linear polymer to the writing monomers were varied to maximize and control the refractive index contrast. A blade-coating-based film preparation method was developed to form films from the mixture of linear polymer and the thiol-ene monomers. This approach results in a holographic material with a peak to mean index contrast (Δ) that reaches 0.04. The refractive index contrast was stable for at least two weeks. Haze in holograms with a high writing monomer loading was significantly reduced when a higher allyl content was incorporated into the binder, resulting in the lowest haze around 0.2%. Finally, the media exhibit high resolution as demonstrated by the ability to record reflection holograms with 140 nm pitch and diffraction efficiency in excess of 90%.
基于光引发硫醇-烯点击化学与用作粘合剂的功能性线性聚合物的独特组合，开发了一种高性能全息记录介质。烯丙基反应位点沿着线性聚合物粘合剂的主链引入，以实现简便的流延成膜，并通过硫醇-烯单体的光聚合促进交联，在这种独特的全息材料方法中，硫醇-烯单体也用作写入单体。改变烯丙基含量以及线性聚合物与写入单体的比例，以最大化和控制折射率对比度。开发了一种基于刮刀涂布的成膜方法，由线性聚合物和硫醇-烯单体的混合物形成薄膜。这种方法得到的全息材料的峰谷折射率对比度（Δ）达到0.04。折射率对比度至少两周内保持稳定。当粘合剂中引入更高的烯丙基含量时，具有高写入单体负载量的全息图中的雾度显著降低，最低雾度约为0.2%。最后，该介质表现出高分辨率，能够记录间距为140nm的反射全息图，衍射效率超过90%。
