Chu Fukai, Hou Yanbei, Liu Longxiang, Qiu Shuilai, Cai Wei, Xu Zhoumei, Song Lei, Hu Weizhao
State Key Laboratory of Fire Science , University of Science and Technology of China , 96 Jinzhai Road , Hefei , Anhui 230026 , P. R. China.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):29436-29447. doi: 10.1021/acsami.9b08734. Epub 2019 Aug 5.
It is still a big challenge to prepare polymer/layered double hydroxide (LDH) composites with high performance, due to the strong agglomeration tendency of LDHs in the polymeric matrix. In this study, to avoid the agglomerated situation, the orientated LDH nanosheets were vertically grown on a ramie fabric surface, which was then embedded in unsaturated polyester resin (UPR) through the combination method of hand lay-up and vacuum bag. Due to the increased contact area and the restricted interfacial slip in the in-plane direction, the hierarchically LDH-functionalized ramie fabrics (denoted as Textile@LDH) significantly enhanced the mechanical performance of UPR composites. Then, the phosphorus- and silicon-containing coating (PSi) was used for the further improvement of the interfacial adhesion. The tensile strength of UPR/Textile@LDH@PSi composites increased by 121.67%, compared to that of neat UPR. The reinforcement mechanism was studied through analyzing the surface nano/microstructure and wetting properties of the raw and modified textiles, as well as the interfacial interaction between the ramie fabrics and UPR. Meanwhile, the thermal stability, thermal conductivity, and flame-retardant performance of ramie-reinforced UPR composites were improved. Particularly, as-prepared hierarchical Textile@LDH@PSi inhibited the heat release during the combustion process of fabric-reinforced UPR composites, and the peak heat release rate and total heat release values decreased by 36.56 and 47.57%, respectively, compared with the neat UPR/Textile composites. The suppression mechanism was further explored by analyzing the microstructure and chemical compositions of char residues. This research paved a feasible solution to improve the poor dispersion of LDHs in polymers and prepared the high-performance UPR composites with multifunctional applications.
由于层状双氢氧化物（LDH）在聚合物基体中具有强烈的团聚倾向，制备高性能的聚合物/LDH复合材料仍然是一个巨大的挑战。在本研究中，为避免团聚情况，将取向的LDH纳米片垂直生长在苎麻织物表面，然后通过手糊和真空袋组合法将其嵌入不饱和聚酯树脂（UPR）中。由于接触面积增加和面内方向界面滑移受限，具有分级结构的LDH功能化苎麻织物（记为Textile@LDH）显著提高了UPR复合材料的力学性能。然后，使用含磷和硅的涂层（PSi）进一步改善界面附着力。与纯UPR相比，UPR/Textile@LDH@PSi复合材料的拉伸强度提高了121.67%。通过分析原始和改性纺织品的表面纳米/微观结构及润湿性，以及苎麻织物与UPR之间的界面相互作用，研究了增强机理。同时，苎麻增强UPR复合材料的热稳定性、热导率和阻燃性能也得到了改善。特别地，制备的分级结构Textile@LDH@PSi抑制了织物增强UPR复合材料燃烧过程中的热量释放，与纯UPR/Textile复合材料相比，峰值热释放速率和总热释放值分别降低了36.56%和47.57%。通过分析残炭的微观结构和化学成分进一步探索了抑制机理。本研究为改善LDH在聚合物中的分散性差问题提供了一种可行的解决方案，并制备了具有多功能应用的高性能UPR复合材料。
