Organic-Inorganic hybrid materials are the materials that combining the characteristics from multiplicated speciality of the organic and inorganic moieties. A series of novel polymer-clay nanocomposite (PCN) encapsulation materials that consist of organic epoxy resin and inorganic nanolayers of montmorillonite clay were prepared through a thermal ring-opening polymerization. The as-synthesized materials were subsequently characterized by Fourier transformation infrared (FTIR) spectroscopy, powder X-Ray diffraction (XRD) pattern and transmission electron microscopy (TEM). Effects of the material composition on the thermal properties and mechanical strength of epoxy resin along with a series of PCN materials, in the form of membrane, were also studied by thermoravimetric analyses (TGA), differential scanning calorimetry (DSC), dynamic mechanical analyzer (DMA) and thermal mechanical analyzer (TMA), respectively. Because of high aspect ratio and platy morphology of clay, we can introduce clay into epoxy to effectively increase the length of the diffusion pathways for water and oxygen as well as decrease the permeability of the bulk epoxy resin.