The influence of the amine/epoxide ratio (N–H/Ep.), controlled from 0.5 to 2.0, on the network structure and mechanical properties of cured epoxy resin (CER) was investigated using a cycloaliphatic epoxy and amine components, in a form of sheets and single-lap joints (SLJs). The cross-linking density and glass transition temperature of CER sheet was the highest at 1:1 stoichiometric N–H/Ep. ratio and became lower with being out of the ratio. On the contrary, tensile strength of sheet and shear strength of SLJ monotonically increased and decreased with an increase in amine content, respectively. Excess amine can work as fillers for sheets and made interfacial strength weaken between adherend and adhesive for SLJs. Changing the N–H/Ep. ratio can control the mechanical properties of not only sheets, but SLJs. Comparisons with mechanical properties of sheets and SLJs are quite helpful to design the high-performance adhesive.

中文翻译：

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胺/环氧基比例对氢化环氧树脂固化片材及单搭接接头交联结构和力学性能的影响

使用脂环族环氧树脂和胺组分，研究了控制在 0.5 至 2.0 之间的胺/环氧化物比率 (N–H/Ep.) 对固化环氧树脂 (CER) 的网络结构和机械性能的影响，形式为板材和单搭接接头 (SLJ)。 CER 片材的交联密度和玻璃化转变温度在化学计量 N-H/Ep 为 1:1 时最高。比率并随着超出该比率而降低。相反，SLJ 的片材拉伸强度和剪切强度分别随着胺含量的增加单调增加和减少。过量的胺可以作为片材的填料，并使 SLJ 的被粘物和粘合剂之间的界面强度减弱。改变 N–H/Ep。比率不仅可以控制板材的机械性能，还可以控制 SLJ 的机械性能。比较片材和 SLJ 的机械性能对于设计高性能粘合剂非常有帮助。