Glass Fibre-Epoxy (GF/Epoxy) composites are being the choice of material when exposed to inorganic acids such as sulphuric acid due to its superior corrosion resistance properties. Water diffusion into GF/Epoxy composites is well-reported. However, inter-relation between acid diffusion mechanism and its analogous influence on chemo-mechanical properties is never investigated with greater details. In this work, the transport behaviour of aqueous 10% sulphuric acid solution into GF/Epoxy composite and its complex inter-relations with the cross-linking density, morphology and mechanical properties is presented. The transport of aqueous solution of 10% sulphuric acid in the composite was quantified by gravimetric analysis and confirmed by the Energy Dispersive X-Ray Spectroscopy (EDX). The kinetic parameters were evaluated and compared using Fickian and Langmuir diffusion models, where the Langmuir model described the transport behaviour better. Analysis of thermomechanical properties such as storage modulus is characterised by dynamic mechanical thermal analysis (DMTA). The free volume distributions are estimated using positron annihilation lifetime spectroscopy (PALS). The indication of an increase in cross-link density with the acid exposure is further validated by Fourier-transform infrared spectroscopy (FT-IR) analysis. In the absence of substantial chemical degradation and with increased cross-linking density, the deterioration in the mechanical properties is attributed to the erosion of epoxy resin confirmed by the morphology performing Field Emission Scanning Electron Microscope (FE-SEM) analysis. The acid diffusion mechanism results show promising prospects of selecting and designing GF/Epoxy composites for industrial storage and manufacturing facilities containing aggressive environments

当玻璃纤维环氧树脂（GF / Epoxy）复合材料暴露于无机酸（例如硫酸）中时，由于其优异的耐腐蚀性能，它们是材料的选择。据报道水扩散到GF /环氧复合材料中。但是，从来没有更详细地研究酸扩散机理及其对化学机械性能的类似影响之间的相互关系。在这项工作中，介绍了10％硫酸水溶液在GF /环氧复合材料中的传输行为以及其与交联密度，形态和机械性能之间的复杂相互关系。用重量分析法定量复合物中10％硫酸水溶液的迁移，并通过能量色散X射线光谱法（EDX）进行确认。使用Fickian和Langmuir扩散模型评估并比较了动力学参数，其中Langmuir模型更好地描述了运输行为。动态力学热分析（DMTA）可以分析热机械性能，例如储能模量。使用正电子an没寿命谱（PALS）估算自由体积分布。通过傅立叶变换红外光谱（FT-IR）分析进一步证实了随着酸暴露而增加的交联密度。在没有明显的化学降解和增加的交联密度的情况下，机械性能的下降归因于通过场发射扫描电子显微镜（FE-SEM）分析的形态所证实的环氧树脂的侵蚀。