Higuchi Chisa, Tanaka Hiromasa, Yoshizawa Kazunari
Institute for Materials Chemistry and Engineering and IRCCS, Kyushu University, Fukuoka, 819-0395, Japan.
J Comput Chem. 2019 Jan 5;40(1):164-171. doi: 10.1002/jcc.25559. Epub 2018 Oct 10.
The molecular mechanism of the adhesion between silica surface and epoxy resin under atmospheric conditions is investigated by periodic density-functional-theory (DFT) calculations. Slab models of the adhesion interface were built by integrating a fragment of epoxy resin and hydroxylated (0 0 1) surface of α-cristobalite in the presence of adsorbed water molecules. Effects of adsorbed water on the adhesion interaction are evaluated on the basis of geometry-optimized structures, adhesion energies, and forces. Calculated results demonstrate that adsorbed water molecules significantly reduce both the adhesion energies and forces of the silica surface-epoxy resin interface. The reduction of adhesion properties can be associated with structural deformation of water molecules confined in the tight space between the adhesive and adherend as well as structural flexibility of the hydrogen-bonding network in the interfacial region during detachment of the epoxy resin from the hydrophilic silica surface. © 2018 Wiley Periodicals, Inc.
通过周期性密度泛函理论（DFT）计算，研究了大气条件下二氧化硅表面与环氧树脂之间的粘附分子机制。在存在吸附水分子的情况下，通过整合环氧树脂片段和α-方石英的羟基化（0 0 1）表面，构建了粘附界面的平板模型。基于几何优化结构、粘附能和力，评估了吸附水对粘附相互作用的影响。计算结果表明，吸附水分子显著降低了二氧化硅表面-环氧树脂界面的粘附能和力。粘附性能的降低可能与限制在粘合剂和被粘物之间紧密空间中的水分子的结构变形以及环氧树脂从亲水性二氧化硅表面分离过程中界面区域氢键网络的结构灵活性有关。© 2018威利期刊公司。
