The impact strength of a newly developed experimental polyurethane-based polymer which is derived from palm oil (Experimental PU) was compared with denture polymers; heat-cured and self cured polymethyl methacrylate (PMMA) and Eclipse ® , light-activated urethane dimethacrylate prosthetic resin system. Ten specimens were prepared using heat-cured PMMA (Meliodent ® Heat Cure, Heraeus Kulzer, Germany), self cured PMMA (Meliodent ® Rapid Repair, Heraeus Kulzer, Germany), Eclipse ® baseplate resin (Dentsply, USA) and Experimental PU material. Specimens were prepared following manufacturer's instructions except for the Experimental PU material where it was prepared in bulk and sectioned to the desired dimension, 64 x 6 x 4 mm. A 'V' notch of approximately 0.8mm in depth was machine cut across the 6mm width. Prior to the Charpy type impact test, specimens were soaked in a water bath for 50 hours at 37ºC. Eclipse ® baseplate resin showed the highest impact strength (2.73 kJ/m 2 ±0.54) followed by Meliodent ® Rapid Repair (2.50kJ/m 2 ±0.65), Meliodent ® Heat Cure (1.96kJ/m 2 ±0.42) and Experimental PU (1.04kJ/m 2 ±0.29). One-way ANOVA showed significant interaction between materials (p<.05) and Tukey HSD revealed that Experimental PU exhibited significantly lower impact strength compared to other materials. Meliodent ® Rapid Repair was not significantly different from Meliodent ® Heat Cure and Eclipse ® baseplate resin. It can be concluded that the Experimental PU exhibited the lowest impact strength while Eclipse ® baseplate resin the highest.

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Poly lactic acid (PLA) is a useful alternative to petrochemical commodity material used in food packaging, due to its low thermal stability and poor crystallization behaviour, it needs to improve its properties in namely terms of thermal and mechanical performance. Neat PLA was reinforced nanofiller TiO2 (titania) to improve its characteristics. Thus, the film of neat PLA and PLA nanocomposites were prepared using solvent casting and hot press methods. Diverse techniques characterized Asprepared films. To enhance the PLA miscibility, TiO2 nanoparticles were homogeneously dispersed in the PLA matrix to attain a low degree of agglomeration as explained by Field Emission Scanning Electron Microscopy (FESEM). Both XRD and differential scanning calorimetry (DSC) analyses of the reinforced nanocomposites disclosed an improvement in their crystallinity increased from 17.52 to 30.91. The dynamic mechanical analysis (DMA) indicated that the storage modulus was improved with increased TiO2 content, increased from 3.13 GPa to 3.26 GPa. Thermogravimetric analysis (TGA) results show that the addition of nanofiller improved thermal stability of the PLA nanocomposites was modified. On the other hand, the reinforced PLA nanocomposites with improved biodegradable behavior were shown to be the potential substitute of conventional petrochemical-based polymers widespread in the food packaging industries.