Department of Bioproducts and Biosystems, School of Chemical Engineering, Aalto University , FI-00076, Espoo, Finland.
Alabama Center for Paper and Bioresource Engineering, Department of Chemical Engineering, Auburn University , Auburn, Alabama 36849-5127, United States.
Biomacromolecules. 2017 Apr 10;18(4):1426-1433. doi: 10.1021/acs.biomac.7b00173. Epub 2017 Mar 22.
The state of dispersion and the interactions between a polymer and a filler in a nanocomposite crucially define its properties and performance. The affinity of polylactide (PLA) with vegetable and animal proteins (casein, gelatin, soy protein isolate, and hydrolysate) is investigated and their role as eco-friendly dispersants and compatibilizers of cellulose nanofibrils (CNF) is elucidated. The affinity of the proteins with PLA is determined by using sensograms acquired by electroacoustic (quartz crystal microgravimetry) and optical (surface plasmon resonance) techniques. The surface energy of PLA increases upon protein adsorption while the opposite effect is observed for CNF, under identical experimental conditions. A significant improvement in the thermodynamic work of adhesion for PLA/CNF systems is predicted by application of the denatured proteins at low concentrations (∼20% and ∼15% enhancement with soy protein and casein at pH 3 and pH 8, respectively). We offer a robust method to screen denatured proteins and to tailor the wettability and material compatibility in the synthesis of bionanocomposites based on CNF and PLA.
在纳米复合材料中，聚合物和填料的分散状态和相互作用对其性能和性能至关重要。研究了聚乳酸（PLA）与植物和动物蛋白（酪蛋白、明胶、大豆蛋白分离物和水解物）的亲和力，并阐明了它们作为纤维素纳米纤维（CNF）的环保分散剂和增容剂的作用。通过使用电化学生物（石英晶体微天平）和光学（表面等离子体共振）技术获得的传感器图来确定蛋白质与 PLA 的亲和力。在相同的实验条件下，蛋白质吸附会增加 PLA 的表面能，而 CNF 则会产生相反的效果。应用变性蛋白质在低浓度下（在 pH 3 和 pH 8 下，大豆蛋白和酪蛋白分别提高了约 20%和 15%），可以预测 PLA/CNF 体系的热力学粘附功有显著提高。我们提供了一种可靠的方法来筛选变性蛋白质，并根据 CNF 和 PLA 合成生物纳米复合材料的润湿性和材料相容性进行调整。
