Bio-inspired cellulose nanofiber-reinforced soy protein resin adhesives with dopamine-induced codeposition of “water-resistant” interphases
Bio-inspired cellulose nanofiber-reinforced soy protein resin adhesives with dopamine-induced codeposition of “water-resistant” interphases
复制标题
多巴胺诱导共沉积“耐水”界面的仿生纤维素纳米纤维增强大豆蛋白树脂胶粘剂
DOI：
10.1016/j.apsusc.2019.01.154
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发表时间：
2019-06
影响因子：
6.7
通讯作者：
Zhong Wang;Shujun Zhao;Wei Zhang;Chusheng Qi;Shifeng Zhang;Jianzhang Li
中科院分区：
文献类型：
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作者：
Zhong Wang;Shujun Zhao;Wei Zhang;Chusheng Qi;Shifeng Zhang;Jianzhang Li
界面强度差和耐水性差是天然纤维增强生物聚合物复合材料充分发挥其优异性能所面临的重大挑战。本文采用贻贝启发的共沉积工艺，在纤维素纳米纤维（CNF）表面合成了具有目标抗水性和高粘附强度的大豆分离蛋白(SPI)/CNF复合粘合剂的纳米结构层。选择可再生资源腰果酚作为环境可持续的间期成分。首先，以腰果酚基缩水甘油酯醚与氨基丙基三乙氧基硅烷为原料，通过环氧化开环反应合成了可水解的烷氧基硅烷腰果酚（ASC）。当组装在cnf上时，ASC/多巴胺系统包覆在每根纤维上，产生纳米结构的聚多巴胺(pDA)/ASC混合涂层，随后在粘合剂制备过程中充当树脂/纤维界面。纳米杂化涂层包含多功能儿茶酚官能团作为“键位”和长脂肪链作为“柔性屏障”。CNF网络的综合优势和外表面的“键合位点和柔性屏障”结构促成了大豆蛋白与纳米纤维之间的强内聚相互作用，从而在两种底物之间形成了活性防水屏障。由于定制的界面相，树脂的粘附性能非常好，湿抗剪强度高达1.27 MPa，分别比纯树脂和原始纤维制备的粘合剂高189%和95%。研究结果表明，可持续腰果酚具有开发防水生物基复合材料的潜力。
Poor interface strength and water resistance are significant challenges in taking full advantage of the excellent performances of natural fiber-reinforced biopolymer composites. Herein, a mussel-inspired co-deposition process was developed to synthesize a nanostructured layer on the surface of cellulose nanofiber (CNF) with target water-resistant property and high adhesion strength of soy protein isolate (SPI)/CNF composite adhesives. Renewable resource cardanol was selected as an environmentally sustainable interphase constituent. First, hydrolyzable alkoxy silane cardanol (ASC) was synthesized via an epoxide ring opening reaction of the cardanol-based glycidyl ether with aminopropyltriethoxysilane. When assembled on the CNFs, the ASC/dopamine system conformally coated every fiber, yielding a nanostructured polydopamine (pDA)/ASC hybrid coating that subsequently acted as the resin/fiber interphases during the adhesive preparation. The nanohybrid coatings contained versatile catechol functional groups as “bonding sites” and long aliphatic chains as a “flexible barrier”. The integrated advantages of the CNF network and the “bonding site and flexible barrier” structures on the outside surface contributed to the strong cohesive interaction between the soy protein and nanofibers, and hence the reactive water-resistant barrier was formed between the two substrates. Thanks to the tailored interphase, the resins achieved impressive adhesion properties with a wet shear strength up to 1.27 MPa, which was 189% and 95% higher than that of the neat resin and the adhesive prepared with pristine fibers, respectively. The findings demonstrate that the sustainable cardanol holds potential for the development of water-resistant biobased composites.