Epoksi termoset polimer sistemlerin mekanik karakteristiklerinin nanoyapılar kullanılarak geliştirilmesi

Epoxy thermoset polymer composites are extensively utilized in a variety of industries, including the automotive, aviation, space, marine and electrical-electronic industries due to their outstanding mechanical, chemical, thermal, and electrical properties. However, since the neat epoxy intrinsically has a brittle structure, it should be incorporated with various particles to improve the fracture resistance and toughness. In this study, silica particles varying with different particle sizes and filler contents were used to prepare diglycidyl ether of bisphenol-A (DGEBPA) epoxy composite cured with methyl tetra hydro phthalic anhydride (MTHPA) to examine the impact of filler content and particle size on the composite's fracture behaviour. In accordance with ASTM-D5045 standard, linear elastic fracture mechanics were used to describe the fracture behaviour of composite materials. It was concluded that the fracture toughness increases with increasing particle size at the micro dimension but decreases inversely when shifted towards the nano dimension. The fracture surfaces were examined by SEM imaging technique, and toughening mechanisms were defined depending on the silica particle size and content. Before the fracture mechanics test studies, a time temperature transformation (TTT) diagram was constructed for the existing epoxy composite system, which can be used as a tool for the optimization of the process parameters.