S2-glass/epoxy polymer nanocomposites: Manufacturing, structures, thermal and mechanical properties

This paper is primarily focused in studying the effects of nanoclay particles such as montmorillonite on improving mechanical and thermal properties of fiber reinforced polymer matrix composite materials. Basic correlations between polymer morphology, strength, modulus, toughness, and thermal stability of thermoset nanocomposites were investigated as a function of layered silicate content. S2-glass/epoxy-clay nanocomposites were manufactured through an affordable vacuum assisted resin infusion method (VARIM). The nanocomposites are formed during polymerization when the adsorbing monomer separates the clay particles into nanometer scales. Transmission electron microscopy (TEM) and wide angle X-ray diffraction(WAXD) were used to characterize the morphology of the dispersed clay particles. The thermal properties such as onset of decomposition and glass transition temperatures were determined by Thermo Gravimetric Analysis (TGA) and Dynamic Modulus Analyzer (DMA). Mechanical properties such as interlaminar shear strength, flexural properties and fracture toughness are also determined for both conventional S2-glass/epoxy composites and S2-glass fiber reinforced nanocomposites. The results show significant improvements in mechanical and thermal properties of conventional fiber reinforced composites with low loading of organo silicate nanoparticles. By dispersing 1% by weight nanosilicates, S2-glass/epoxy-clay nanocomposites attributed to almost 44, 24 and 23% improvement in interlaminar shear strength, flexural strength and fracture toughness in comparison to conventional S2-glass/epoxy composites. Similarly, the nanocomposites exhibit approximately 26degreesC higher decomposition temperatures than that of conventional composites. This improved properties of fiber reinforced polymer nanocomposites are achieved mostly due to increased interfacial surface areas, improved bond characteristics and intercalated/exfoliated morphology of the epoxy-clay nanocomposites. The TEM observations provide evidence of detailed morphology of the polymer layered-clay nanocomposites.