Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden; Wallenberg Wood Science Center, Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 56-58, 100 44 Stockholm, Sweden.
Carbohydr Polym. 2022 Nov 1;295:119867. doi: 10.1016/j.carbpol.2022.119867. Epub 2022 Jul 14.
A novel method is reported for the preparation of a hybrid gibbsite-cellulose nanofibril (CNF) nanocomposite film with improved wet and dry mechanical properties and barrier properties. A gibbsite and cationic CNF dispersion was dewatered at pH 7 to prepare well-ordered films. Thereafter, the charge on gibbsite was reversed by dipping the film in pH 12 water to induce an ionic interaction between CNFs and gibbsite, enhancing the film properties; modulus improved from 9 GPa to 12 GPa, with a maintained strain-at-break of 6 % and tensile strength of 190 MPa. Additionally, the charge-reversed film swelled a factor of 24 less than a film without any gibbsite. At 23 °C and 80 % RH, the oxygen barrier properties were improved by a factor of 28, to a value of 18 ml·μm·m·kPa·24 h and the water vapour barrier properties were improved by a factor of 12, to a value of 105 g·μm·m·kPa·24 h.
本文报道了一种制备具有改善的湿态和干态机械性能和阻隔性能的水滑石-纤维素纳米纤维（CNF）杂化纳米复合膜的新方法。在 pH 值为 7 下对水滑石和阳离子 CNF 分散体进行脱水以制备有序的薄膜。此后，通过将薄膜浸入 pH 值为 12 的水中使水滑石的电荷反转，从而在 CNF 和水滑石之间诱导离子相互作用，增强了薄膜性能；模量从 9 GPa 提高到 12 GPa，同时保持断裂伸长率为 6%和拉伸强度为 190 MPa。此外，与没有水滑石的薄膜相比，电荷反转后的薄膜的溶胀度低 24 倍。在 23°C 和 80%RH 下，氧气阻隔性能提高了 28 倍，达到 18 ml·μm·m·kPa·24 h，水蒸气阻隔性能提高了 12 倍，达到 105 g·μm·m·kPa·24 h。
