STUDY OF FLEXURAL AND IMPACT PROPERTIES OF NANO-HYBRID COMPOSITES MATERIALS BY USING POLY METHYL METHACRYLATE (PMMA) MATRIX

The present work studies the effect of adding nano-silica (nano-SiO2) particles, that were added with different volume fractions of (0.5 %, 1 % and 1.5 %), and random woven fiber glass with fixed volume fraction of (3 %), on some mechanical properties of composite prosthesis complete denture base materials by using poly methyl methacrylate (PMMA) resin as matrix. In this work, the prosthetic dentures base specimens consist of two groups include particulate composites materials and nano-hybrid laminated composites materials, according to the types of reinforced materials that were prepared by using Hand Lay-Up method, the first group consists of PMMA resin reinforced by nano- silica particles, only, while the second group consists of PMMA resin reinforced by nano- silica particles and random woven fiber glass. The mechanical tests were performed on these specimens include (flexural and impact tests). The results showed that the addition of (nano-SiO2) particles has a noticeable effect on the most properties of particulate composite material specimens and nano-hybrid laminated composites materials specimens for prosthetic denture base, the values of (flexural modulus, flexural strength, shear stress and impact strength) properties increased with the increase of the volume fraction of (nano-SiO2) particles in the composite denture base material, whereas the values of (flexural strain) property decreased.