Swain Aparna, Das A Nimmi, Chandran Sivasurender, Basu J K
Department of Physics, Indian Institute of Science, Bangalore, 560012, India.
Department Physik, Universität Siegen, Walter-Flex-Strasse 3, 57072 Siegen, Germany.
Soft Matter. 2022 Feb 2;18(5):1005-1012. doi: 10.1039/d1sm01681d.
High density functional polymer nanocomposites (PNCs) with high degree of dispersion have recently emerged as novel materials for various thermo-mechanical, optical and electrical applications. The key challenge is to attain a high loading while maintaining reasonable dispersion to attain maximum possible benefits from the functional nanoparticle additives. Here, we report a facile method to prepare polymer grafted nanoparticle (PGNP)-based high density functional polymer nanocomposites using thermal activation of a high density PGNP monolayer to overcome entropic or enthalpic barriers to insertion of PGNPs into the underlying polymer films. We monitor the temperature-dependent kinetics of penetration of a high density PGNP layer and correlate the penetration time to the effective enthalpic/entropic barriers. The experimental results are corroborated by coarse-grained molecular dynamics simulations. Repeated application of the methodology to insert nanoparticles by appropriate control over temperature, time and graft-chain properties can lead to enhanced densities of loading in the PNC. Our method can be engineered to produce a wide range of high density polymer nanocomposite membranes for various possible applications including gas separation and water desalination.
具有高度分散性的高密度功能聚合物纳米复合材料（PNCs）最近已成为用于各种热机械、光学和电气应用的新型材料。关键挑战在于在保持合理分散的同时实现高负载量，以便从功能性纳米颗粒添加剂中获得最大可能的益处。在此，我们报告一种简便的方法，通过对高密度聚合物接枝纳米颗粒（PGNP）单层进行热活化，以克服PGNP插入下层聚合物薄膜时的熵或焓障碍，从而制备基于PGNP的高密度功能聚合物纳米复合材料。我们监测高密度PGNP层渗透的温度依赖性动力学，并将渗透时间与有效焓/熵障碍相关联。粗粒度分子动力学模拟证实了实验结果。通过适当控制温度、时间和接枝链性质，重复应用该方法来插入纳米颗粒，可提高PNC中的负载密度。我们的方法经过设计，可生产出用于各种可能应用（包括气体分离和水脱盐）的多种高密度聚合物纳米复合膜。
