Mechanical Engineering Department, Universitat Rovira i Virgili, 43003 Tarragona, Spain.
Chemical Engineering Department, Universitat Rovira i Virgili, 43003 Tarragona, Spain.
Molecules. 2020 Apr 3;25(7):1660. doi: 10.3390/molecules25071660.
The main objective of this work was to further analyze the optimization of the production factors of L. fiberboards obtained without adhesives. The production of boards derived from L. without added adhesives and with high mechanical performance has already been demonstrated. This present study explored a modification in the production process through a final curing thermal treatment (final heat treatment, FHT). Since pressing time is an influential factor in the production cost, it is expected that curing allows a reduction of this time. This study compared the results obtained by three panel-production alternatives: long pressing time (tp) without curing and long and short tp with FHT. Of the two factors analyzed, pressing pressure (Pp) was the most important production factor in both the modulus of elasticity (MOE) and modulus of rupture (MOR), while curing was the most important factor for the internal bond (IB). The study shows that a FHT facilitates the distribution of lignin and a possible improvement in the quantity and quality of bonds between lignin and cellulosic fibers. As a consequence, it improves the IB, produces boards with more homogeneous physical and mechanical properties and thereby makes them more hydrophobic. The curing thermal treatment allows high performance panels to be obtained in a manner which is more ecological, quicker, and cheaper.
本工作的主要目的是进一步分析无胶生产 LF 纤维板的生产因素的优化。已经证明了无添加胶黏剂且具有较高机械性能的 LF 板材的生产。本研究通过最终热固化处理（最终热处理，FHT）探索了生产工艺的改进。由于压制时间是生产成本的一个影响因素，预计固化可以减少此时间。本研究比较了三种板生产替代方案的结果：无固化的长压制时间（tp）和长、短 tp 与 FHT。在分析的两个因素中，压制压力（Pp）是弹性模量（MOE）和断裂模量（MOR）的最重要的生产因素，而固化是内结合强度（IB）的最重要因素。研究表明，FHT 有助于木质素的分布，并可能改善木质素与纤维素纤维之间的结合数量和质量。因此，它提高了 IB，生产出物理和机械性能更均匀的板材，并使它们具有更高的疏水性。固化热处理可以以更生态、更快和更经济的方式获得高性能板材。
