An anionic polyelectrolyte hybrid for wood-polyethylene composites with high strength and fire safety via self-assembly
An anionic polyelectrolyte hybrid for wood-polyethylene composites with high strength and fire safety via self-assembly
复制标题
通过自组装制备具有高强度和防火安全性的木质-聚乙烯复合材料的阴离子聚电解质杂化物
DOI：
10.1016/j.conbuildmat.2020.118661
复制
发表时间：
2020-07-10
影响因子：
7.4
通讯作者：
Mei, Changtong
中科院分区：
文献类型：
--
作者：
Ding, Chunxiang;Pan, Mingzhu;Mei, Changtong
木塑复合材料（WPC）作为一种可再生、可持续发展的材料受到广泛关注，但其固有的易燃性极大地限制了其在住宅建筑等领域的广泛应用。它是由聚磷酸铵（APP）和纤维素纳米晶体（CNC）通过离子键和氢键自组装而成。APP-CNC杂化材料之间的物理交联网络使整个材料同时具有高的承载能力和良好的变形能力。数字图像相关分析（DIC）结果表明，应变通过氢键作用形成的物理交联网络从HDPE分子均匀地传递到木材纤维上，从而增加了WPC/APP-CNC复合材料的高变形区域，且高变形区域分布均匀。与纯WPC相比，WPC/APP-9wt%CNC复合材料的拉伸强度和杨氏模量分别提高了42.69%和75.90%。在热解过程中，CNC促进混合物提前热解（T-5%的298摄氏度），并提供碳骨架成炭。同时，物理交联网络的存在使木质纤维素在燃烧过程中的残炭结构更加致密，石墨化程度更高。对于WPC/APP-9wt%CNC，其平均热释放量和总热释放量与纯WPC相比分别显著降低62.6%和23.8%。本研究表明，该复合材料在制备高性能、高功能、高附加值的木塑复合材料方面具有潜在的应用前景。(C)2020爱思唯尔有限公司保留所有权利。
Wood-plastic composite (WPC), as a renewable and sustainable material, has received wide attention, but its inherent flammability greatly limits its broad application in residential construction and so on. In this work, an anionic polyelectrolyte hybrid (APP-CNC) was built and applied to derive simultaneously flame-retardancy-improved and mechanically strengthened WPC. It was constructed with ammonium polyphosphate (APP) and cellulose nanocrystals (CNC) by self-assembly with ionic and hydrogen bonding. The physical crosslinking network between APP-CNC hybrid enabled the whole materials possess both high load capacity and good deformation capacity synchronously. According to the digital image correlation (DIC), the strain transferred uniformly from HDPE molecular to wood fibers via the physical crosslinking network based on hydrogen bonding, and hence an increased high deformation region occurred and distributed uniformly in WPC/APP-CNC. Compared with neat WPC, the tensile strength and Young's modulus of WPC/APP-9 wt%CNC increased by 42.69% and 75.90%, respectively. During pyrolysis, CNC promoted hybrid to pyrolyze ahead (T-5% of 298 degrees C) and provided a carbon skeleton for char forming. Meanwhile, physical crosslinking network further caused a more compact char residue with a higher graphitization during combustion of WPC. For WPC/APP-9 wt%CNC, it had a significant decrease in average heat release and total heat release of 62.6%, and 23.8% respectively, compared with those of neat WPC. This work indicated that polyelectrolyte hybrid had a potential application prospect in preparation of high-performance, high-function and high-value-added WPC. (C) 2020 Elsevier Ltd. All rights reserved.