The influence of the shape and size of the AL2O3 particles on the flexural properties of the PMMA composite modified by the addition of dimethyl itaconate

Dental materials have specific requirements regarding behavior in exploitation conditions. Poly (methyl methacrylate) (PMMA) is one of the most commonly used prosthetic materials. It is of interest to improve the mechanical properties of the polymer matrix by adding reinforcements in the form of ceramic particles. It has been shown that adding very small amounts of particles to the material, substantially improved mechanical properties of PMMA modified by dimethyl itaconate (PMMA/DMI). In this paper, different sorts of alumina fillers will be examined. Commercial alumina particles and micro particles of alumina obtained from the sol-gel technique influence the mechanical properties of the composite material obtained. Sol-gel techniques was the mean to synthesize pure alumina particles and ferrous oxide doped alumina particles. Composites are prepared with 1 wt. %, 3 wt. % and 5 wt. % of alumina based particles. It has been shown that all the tested fillers improve the flexular properties of the material relative to the pure matrix PMMA/DMI and the most suitable concentration of fillers was 1 wt. %. Among the types of fillers tested alumina particles obtained by sol-gel technique, perfomed in the best way in improving the flexural strength and modulus.