Yapar Özkan, Piltonen Petteri, Hadela Ajra, Lobnik Aleksandra
Faculty of Mechanical Engineering, University of Maribor, Smetanova Ulica 17, 2000 Maribor, Slovenia.
Institute for Environmental Protection and Sensors (IOS) Ltd., Beloruska Ulica 7, 2000 Maribor, Slovenia.
Polymers (Basel). 2024 Jul 5;16(13):1921. doi: 10.3390/polym16131921.
The increasing awareness of global ecological concerns and the rising sustainability consciousness associated with the manufacturing of non-renewable and non-biodegradable composite materials have led to extensive research on product and process developments of more sustainable, environmentally friendly, and fully biodegradable biocomposites for higher-value end-use applications. All-cellulose composites (ACCs) are an emerging class of biocomposites, which are produced utilizing solely cellulose as a raw material that is derived from various renewable biomass resources, such as trees and plants, and are assessed as fully biodegradable. In this study, sustainable ACCs were fabricated for the first time based on the full dissolution of commercially available sulfite dissolving (D) pulps as a matrix with concentrations of 1.5 wt.% and 2.0 wt.% in an aqueous NaOH-urea solvent, and they were then impregnated on/into the pre-fabricated birch (B), abaca (A), and northern softwood (N) fiber sheets as reinforcements by the vacuum-filtration-assisted impregnation approach. This research aimed to investigate the effects of the impregnated cellulose matrix concentrations and types of the utilized cellulose fiber reinforcements (B, A, N) on the morphological, crystalline, structural, and physio-mechanical properties of the ACCs. The highest degrees of improvements were achieved for tensile strength (+532%, i.e., from 9.24 MPa to 58.04 MPa) and strain at break of the B fiber-reinforced ACC B (+446%, i.e., from 1.36% to 4.62%) fabricated with vacuum impregnation of the 1.5 wt.% cellulose matrix. Noticeably, the greatest improvements were attained in strain at break of the A and N fiber-reinforced ACCs A (+218%, i.e., from 4.44 % to 14.11%) and N (+466%, i.e., 2.59% to 14.65%), respectively, produced with vacuum impregnation of the 2.0 wt.% cellulose matrix. The study highlights the diverse properties of the all-cellulose biocomposite materials that could, expectedly, lead to further development and research for upscaled production of the ACCs.
全球对生态问题的关注度日益提高，以及与不可再生和不可生物降解复合材料制造相关的可持续发展意识不断增强，促使人们对更可持续、环保且完全可生物降解的生物复合材料进行广泛研究，以用于高价值终端应用的产品和工艺开发。全纤维素复合材料（ACC）是一类新兴的生物复合材料，它仅以纤维素为原料生产，纤维素来源于各种可再生生物质资源，如树木和植物，并且被评估为完全可生物降解。在本研究中，首次基于将市售亚硫酸盐溶解浆（D）作为基质，以1.5 wt.%和2.0 wt.%的浓度在NaOH - 尿素水溶液中完全溶解来制备可持续的ACC，然后通过真空过滤辅助浸渍法将其浸渍在预制的桦木（B）、马尼拉麻（A）和北方软木（N）纤维片材上/内作为增强材料。本研究旨在研究浸渍纤维素基质浓度和所用纤维素纤维增强材料（B、A、N）的类型对ACC的形态、结晶、结构和物理机械性能的影响。对于用1.5 wt.%纤维素基质真空浸渍制备的B纤维增强ACC B，拉伸强度提高幅度最大（+532%，即从9.24 MPa提高到58.04 MPa），断裂应变提高幅度最大（+446%，即从1.36%提高到4.62%）。值得注意的是，对于用2.0 wt.%纤维素基质真空浸渍制备的A纤维增强ACC A（+218%，即从4.44%提高到14.11%）和N纤维增强ACC N（+466%，即从2.59%提高到14.65%），断裂应变分别取得了最大程度的提高。该研究突出了全纤维素生物复合材料的多种性能，有望推动ACC大规模生产的进一步开发和研究。
