The size effects of micron particles on the physico-mechanical properties of resinous composites containing inorganic-organic dual fillers

Abstract

In this study, thermal polymerized resinous composites containing inorganic-organic dual fillers were developed. The size effects of micron particles on the physico-mechanical properties of composites were investigated. According to the standard BS EN ISO 4049, the degree of transformation, hardness, three-point flexural strength, water absorption and water solubility of the prepared composite materials were determined. Contrary to expectations, the degree of transformation of the composites increased as the micron particle size increased. It has been deduced that this increase is directly related to the varying surface areas depending on the particle sizes and the modification rates that can vary depending on the surface areas. The hardness values did not show a general trend with increasing particle size. When the flexural strengths of composites containing varying micron size particles were examined, their strengths differed in relation to the degree of transformation and the rate of modification, which is also effective in hardness. As with other properties, the effects of competing particle size and rate of modification had an effect on the absorption behavior. When the resolutions of the composites are examined, the values of all are positive. It was concluded that this situation may be due to the absence of polar groups in the main monomer structure other than ester, hydroxyl and urethane groups, which will keep the absorbed water in the structure, and the release of unreacted monomers with the absorbed water.