This study involves on manufacture of denture base resin with advanced physical properties through the addition of two type of synthetic fibers used as reinforcing materials polypropylene (PP) and Poly acrylonitrile (PAN). In this research, groups of three samples of both PMMA/PP and PMMA/PAN composites were prepared with the selected fiber weight ratios of 1.5, 3.5, 5.5 and 7.5 %Wt. Physical properties such as water absorption, thermal conductivity and density were evaluated under normal conditions. The chemical bond structure was also investigated for all samples using FTIR test. The results showed that when fibers ratio increased until 7.5 %Wt., the water absorption increases, as well for each fiber which was over 0.6% compared to the 0.3% of the neat sample. A noticeable decrease in the thermal conductivity property from 0.33 W/m.K for PMMA/PP and 0.24 W/m.K for PMMA/PAN comparing to 0.46 W/m. K of the neat polymer was revealed. As for the density results, it was found that when the fibers ratios were increased, the sample density slightly decreased and reached 1.09 g/cm 3 for PMMA/PP and 1.1 g/cm 3 for PMMA/PAN at the maximum fibers rate. FTIR results indicated there was no new peaks appeared after reinforcement with both fibers. This could refer to the good physical bond between the mixtures, no new material formed.

Poly methyl methacrylate PMMA polymer is used continuously and popular in dental applications during the previous years because it has a set of good properties, including ease of manufacture, light weight, low cost and others. Yet, it has weak mechanical properties under pressure for a long time. The aim of this research was to manufacture composite material with advance mechanical properties by adding two types of fibers, (polypropylene PP and Poly acrylonitrile PAN) to the matrix polymer PMMA. In this research, groups of composite samples were prepared with selected weight ratios of both fibers (1.5, 3.5, 5.5 and 7.5 wt. %). Compression strength, hardness value and surface roughness in addition to the Morphology examination were the properties that been evaluated in the normal circumstances. The results showed an increase in compressive strength, hardness and surface roughness, during the increase of reinforcing ratio of the fibers. There was a clear increase in the compressive strength during the increase in the weight ratio of both types of fibers, the largest value was (300MPa) for PMMA/PAN samples that obtained at the highest reinforcing ratio compared to (240 MPa and 119 MPa) PMMA/PP and the neat PMMA, respectively. The hardness increases noticeable with the increase of both type of fibers the reinforcement ratio, and reaches its highest value at the ratio of (7.5wt.%) for both type (87), compared to the neat sample (81). On the other hand, surface roughness increased during the increase of fibers ratio used which negatively affected the samples comparing to the neat polymer. Through SEM test, it was found that the fracture surface of the neat PMMA was homogeneous, while it is almost continuous for both PMMA/PP and PMMA/PAN.