A study of the effect of silica particles addition on some physical properties of PVC as a packaging material


In this work, varying compositions of SiO2 micro filler were added with the Polyvinyl Chloride (PVC) and samples have been prepared using film casting technique. The results have been analyzed and compared for PVC samples with (1 wt%, 3 wt%, 5 wt% and 10 wt%) SiO2 micro filler. Mechanical characteristics such as tensile strength, elongation at break and Young`s modulus were measured for all the samples, where the tensile strength was increased from 8.39 Mpa for purified PVC to 16 Mpa for 3% SiO2/PVC composite. Also, thermal conductivity measurement values illustrated that composite materials have a good thermal insulation at 10 wt. %, thermal conductivity was decreased from 0.1684 W/m. K for PVC to 0.1310W/m. K at 10% SiO2/PVC composite. Absorptivity test was also carried out for these samples, the results of this study proved that PVC and SiO2-PVC composites have low diffusion coefficients ranging from (10-13- 10-10 m2/s). Similarly, the dielectric properties like dielectric constant, loss factor, resistance, and volume resistivity were performed; the dielectric constant was increased from 2.1039 for PVC to 3.658 for 3% SiO2/PVC composites, while the dielectric loss factor was decreased from 0.0144 for PVC to 0.0137 for 5%SiO2/PVC composite. The values of resistance were increased from 17259.99(Ω) for purified PVC to 29185.75(Ω) for 10% SiO2/PVC composites. Volume resistivity was increased from 0.3794 x109 (Ω. cm) for PVC to 0.5179x109 (Ω. cm) for 10% SiO2/PVC composites. FTIR spectroscopy was employed for all PVC-composite samples and its results were investigated, there are systematic increases in absorbance intensity spectra with SiO2 ratios attributed to good distribution of inorganic fillers (Symmetric increases). The microstructure and morphology of the prepared samples were investigated by using optical microscope. It can be observed that, the samples with (3% SiO2/PVC) are glossy and smooth without agglomeration of (SiO2) particles in (PVC) matrix. The results demonstrate that PVC-composite films prepared in this study show promising potential to achieve good materials for plastic packaging applications.