In this paper, copper nanoparticles (CuNPs) with a particle size of 40 nm were used to prepare a copper paste by using a liquid phase reduction method with Poly vinyl pyrrolidone (PVP) aqueous solutions in ethanol with different concentrations of CuNPs. Many thermal properties were characterized such as scanning electron microscopy (SEM), viscosity, thermal conductivity, PVP has properties such as a surface stabilizer, growth modifier, nanoparticle dispersant, and reducing agent. The influence of CuNPs particle volume fraction of (0.1, 0.2, 0.3 and 0.5%) with PVP on the thermal conductivity, pH and viscosity values of CuNPs./PVP were characterized. The experimental data show that the thermal conductivity of composites increases with the increase of filler. The enhancement of thermal conductivity is 62 % at 0.5% of the volume concentration at 25°C from the base PVP colloidal.

Poly(vinyl chloride) (PVC) is one of the versatile thermoplastic materials that have tremendous applications almost everywhere but it is thermally unstable at high temperatures. Processing of PVC at elevated temperatures requires the use of thermal stabilizers that are considered crucial additives for the protection of PVC during both processing and useful life usage. Several thermal stabilizers are available commercially that mostly obstruct the dehydrochlorination reaction. Choosing appropriate stabilizer systems for a specific application is cumbersome. A Brabender torque rheometer at a constant temperature of 180°C and variable shear stress was used to evaluate the stabilizing efficiency of 12 different stabilizer systems combined with PVC. Fusion time, induction period, minimum torque, and rheological stability time were determined in order to evaluate the investigated stabilizer systems. It was found that dibutyl tin mercaptide was the best stabilizer, while the mixture of lead stabilizers was the worse one.

Xanthan gum is a nontoxic polysaccharide with a good gelling, thickening and stabilizing attributes, and used widely in food and cosmetic industries. Effect of temperature on the viscosity and density of various solutions of xanthan gum (0.1 ,0.2,0.3,0.4 and 0.5 w/v %) were studied experimentally with temperatures range of 30 to 60 C. The experimental tests were performed using DV-II+Pro viscometer at different speeds (50, 100 and 150rpm). It has been noticed by measuring the viscosity changes, that efficiency of higher polymer concentrations , lower speeds and lower temperatures also. The density increase by increasing concentration and decrease with temperatures

The reducing of exhaust emissions is an essential issue for environmental organizations in the world. In the current research, emissions of SI engines were reduced by using Alumina (AL2O3) and titanium dioxide (TiO2) nanoparticles as additives to the high octane gasoline fuel used in the SI engine. 30 nm Alumina and titanium dioxide nanoparticles were mixed with high octane gasoline fuel at different concentrations. Different tests were carried out for the high-octane gasoline fuel before and after adding the nanoparticles, including thermal conductivity, viscosity, PH, density, morphology. Tests of the percentage of CO and O2 emissions were also performed for the exhaust gases of the SI engine. Results show an increase in thermal conductivity from 0.14 to 0.15 and 0.154 (W/m.k) respectively of AL2O3 and TiO2 nanofluid at 1% of volume concentration compared to the base fluid. Viscosity and density also showed an increase with increasing nanoparticle concentrations in the high-octane gasoline fuel. A decrease in the PH value of the high-octane gasoline fuel with an increase in nanoparticle concentrations was also observed. An improvement was noted in reducing carbon dioxide pollution emissions by alumina and titanium dioxide nanoparticles.

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