Faculty of Chemistry, Institute of Polymer and Dye Technology, Lodz University of Technology, Stefanowskiego 12/16, 90-924 Lodz, Poland.
PPGE3M, Federal University of Rio Grande do Sul-UFRGS, Av. Bento Gonçalves 9500, Porto Alegre 91501-970, Brazil.
Int J Mol Sci. 2021 Oct 18;22(20):11203. doi: 10.3390/ijms222011203.
This study aims to evaluate the influence of using a bleached Curauá fiber (CF) as filler in a novel rigid polyurethane foam (RPUF) composite. The influence of 0.1, 0.5 and 1 wt.% of the reinforcements on the processing characteristics, cellular structure, mechanical, dynamic-mechanical, thermal, and flame behaviors were assessed and discussed for RPUF freely expanded. The results showed that the use of 0.5 wt.% of CF resulted in RPUF with smoother cell structure with low differences on the processing times and viscosity for the filled pre-polyol. These morphological features were responsible for the gains in mechanical properties, in both parallel and perpendicular rise directions, and better viscoelastic characteristics. Despite the gains, higher thermal conductivity and lower flammability were reported for the developed RPUF composites, related to the high content of cellulose and hemicellulose on the bleached CF chemical composition. This work shows the possibility of using a Brazilian vegetable fiber, with low exploration for the manufacturing of composite materials with improved properties. The developed RPUF presents high applicability as enhanced cores for the manufacturing of structural sandwich panels, mainly used in civil, aircraft, and marine industries.
本研究旨在评估使用漂白 Curauá 纤维 (CF) 作为新型硬质聚氨酯泡沫 (RPUF) 复合材料填料的影响。评估并讨论了 0.1、0.5 和 1wt.% 增强剂对 RPUF 自由膨胀的加工特性、细胞结构、机械性能、动态机械性能、热性能和阻燃性能的影响。结果表明，使用 0.5wt.%的 CF 使 RPUF 具有更光滑的细胞结构，填充预聚体的加工时间和粘度差异较小。这些形态特征有助于提高机械性能，无论是在平行还是垂直上升方向上，并且具有更好的粘弹性特性。尽管有这些优势，但所开发的 RPUF 复合材料的导热系数更高，阻燃性更低，这与漂白 CF 化学成分中纤维素和半纤维素的高含量有关。这项工作展示了使用巴西植物纤维的可能性，这种纤维在制造具有改善性能的复合材料方面的探索较少。所开发的 RPUF 作为增强芯材具有很高的适用性，可用于制造结构夹层板，主要用于民用、航空和海洋等行业。
