Protein derived adhesives are extensively explored as a replacement for synthetic ones, but suffers from weak adhesion and water resistance. Graphite oxide (GO) has been extensively used in nanocomposites, but not in adhesives applications. The objectives of this study were to prepare functionally improved protein adhesive by exfoliating GO with different oxidation levels, and to determine the effect of GO on adhesion mechanism. GO were prepared by oxidizing graphite for 0.5, 2, and 4 h (GO-A, GO-B and GO-C, respectively). Increasing oxidation time decreased C/O ratio; while the relative proportion of C-OH, and C = O groups initially increased up to 2 h of oxidation, but reduced upon further oxidation. Canola protein-GO hybrid adhesive (CPA-GO) was prepared by exfoliating GO at a level of 1% (w/w). GO significantly increased (p < 0.05) adhesion; where GO-B addition showed the highest dry, and wet strength of 11.67 ± 1.00, and 4.85 ± 0.61 MPa, respectively. The improvements in adhesion was due to the improved exfoliation of GO, improved adhesive and cohesive interactions, increased hydrogen bonding, increased hydrophobic interactions and thermal stability of CPA-GO. GO, as we proposed for the first time is easier to process and cost-effective in preparing protein-based adhesives with significantly improved functionalities.

中文翻译：

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氧化石墨可改善低芥酸菜籽蛋白-氧化石墨杂化胶的粘合性和耐水性。

广泛探索了蛋白质衍生的粘合剂，以替代合成粘合剂，但其粘合力弱和耐水性差。氧化石墨（GO）已被广泛用于纳米复合材料，但尚未用于粘合剂应用中。这项研究的目的是通过剥落具有不同氧化水平的GO来制备功能改良的蛋白质粘合剂，并确定GO对粘附机制的影响。通过氧化石墨0.5、2和4小时（分别为GO-A，GO-B和GO-C）来制备GO。增加氧化时间会降低C / O比；而C-OH和C = O基团的相对比例最初增加到2 h氧化，但在进一步氧化时降低。通过以1％（w / w）的水平对GO进行去角质来制备Canola蛋白-GO混合粘合剂（CPA-GO）。GO显着增加（p <0.05）粘附力；其中添加GO-B表现出最高的干强度和湿强度，分别为11.67±1.00和4.85±0.61 MPa。粘附力的改善归因于GO的剥离改善，粘附力和内聚力的改善，氢键的增加，CPA-GO疏水性的增加和热稳定性。正如我们第一次提出的那样，GO在制备功能显着改善的蛋白质基胶粘剂时更容易加工且具有成本效益。