In this paper, three kinds of ZnS NPs capping different amount of mercaptoethanol (ME) were synthesized, and the effect of capping amount on ZnS NPs was studied, indicating that the capping amount of ME on ZnS surface decreases, while ZnS size increases as the decrease of added capping agent in synthesis process, and ZnS NP capping middle amount of ME (~27.7 wt%) shows a highest apparent refractive index (RI) value. ZnS NPs were composited into polymeric matrices by a simple “one-step” thermocuring method characterized by adding a small amount of functional monomer of glycidyl methacrylate (GMA) and solvent of N,N-dimethylformamide (DMF) The reaction mechanism, studied by ¹H NMR spectra, indicates that the epoxy of GMA monomer can be easily opened and chemically grafted on ME-capped ZnS surface under the catalysis of DMF, and then copolymerized with other monomer. By the route, ZnS NPs can be composited into pure poly(N,N-dimethylacrylamide)-type (DMA-type), DMA-type copolymer, and DMA-free matrices to fabricate transparent films, and its RI value can be improved by either optimizing capping amount on ZnS surface or increasing ZnS content in the nanocomposites. The RI value of resulting dried nanocomposites can be improved to 1.764 by compositing 80 wt% ZnS capping middle amount of ME.

中文翻译：

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包含悬垂不同巯基乙醇含量的悬垂ZnS纳米晶体的高折射率聚合物纳米复合材料的简单合成

本文合成了三种覆盖不同巯基乙醇（ME）含量的ZnS NPs，研究了封端量对ZnS NPs的影响。合成过程中添加的封端剂数量减少，ME的ZnS NP封端中间量（〜27.7 wt％）显示出最高的表观折射率（RI）值。ZnS NPs通过简单的“一步式”热固化方法复合到聚合物基体中，该方法的特征是添加少量的甲基丙烯酸缩水甘油酯（GMA）的功能单体和N，N-二甲基甲酰胺（DMF）的溶剂。反应机理由¹研究，1 H NMR光谱表明，在DMF的催化下，GMA单体的环氧树脂可以很容易地打开并化学接枝在ME封端的ZnS表面上，然后与其他单体共聚。通过这种途径，可以将ZnS NPs合成为纯聚（N，N-二甲基丙烯酰胺）型（DMA型），DMA型共聚物和无DMA基质，以制备透明膜，并且可以通过以下方法提高RI值优化ZnS表面的封端量或增加纳米复合材料中ZnS的含量。通过复合中等含量的80％ZnS封端的ME，可以将所得干燥纳米复合材料的RI值提高至1.764。