Chemical Engineering Department, Faculty of Science, University of Córdoba, Córdoba 14014, Spain.
Chemical Engineering Department, Faculty of Science, University of Córdoba, Córdoba 14014, Spain.
Int J Biol Macromol. 2019 Dec 1;141:197-206. doi: 10.1016/j.ijbiomac.2019.08.262. Epub 2019 Aug 31.
Nanocelluloses with and without residual lignin were isolated from wheat straw. In addition, the effect of TEMPO-mediated oxidation on the production of lignin-containing nanocellulose was studied. The different nanocelluloses were used as reinforcing agent in Poly(vinyl alcohol) films. The morphology, crystallinity, surface microstructure, barrier properties, light transmittance, mechanical and antioxidant properties were evaluated. The translucency of films was reduced by the addition of nanocellulose, however, the ability to block UV-light increased from 10% for PVA to >50% using lignin-containing nanocellulose, and 30% for lignin-free samples. The mechanical properties increased considerably, however, for loads higher than 5% a negative trend was observed presumptively due to a clustering of nanocellulose components in PVA matrix. The barrier properties of the films were improved with the use of nanocellulose, especially at small amounts (1-3%). The antioxidant capacity of films was increased up to 10% using lignin-containing nanocellulose compared to 4.7% using PVA.
从麦秆中分离出了含有和不含有残余木质素的纳米纤维素。此外，还研究了 TEMPO 介导的氧化对含木质素纳米纤维素生产的影响。不同的纳米纤维素被用作聚乙烯醇薄膜的增强剂。评估了形态、结晶度、表面微观结构、阻隔性能、透光率、机械性能和抗氧化性能。添加纳米纤维素会降低薄膜的透明度，但使用含木质素纳米纤维素可将阻挡紫外线的能力从 PVA 的 10%提高到>50%，而无木质素的样品则提高到 30%。机械性能有了显著提高，但在高于 5%的负载下，由于纳米纤维素成分在 PVA 基体中的聚集，可能会出现负面趋势。使用纳米纤维素可以改善薄膜的阻隔性能，特别是在使用少量（1-3%）纳米纤维素时。与使用 PVA 相比，使用含木质素纳米纤维素可使薄膜的抗氧化能力提高 10%，达到 4.7%。
