The technological properties of composite materials (thermal, strength, rheology, electrical and morphology) are very important parameters for high-performance applications. In this study, we aimed to improve the properties of PVA by using carbon materials obtained by the pyrolysis of waste tires, with the aim of recycling them instead of disposing of them. For this purpose, PVA biocomposite films containing carbonized waste rubber at different rates were prepared. The thermal properties of the prepared biocomposite films were examined via thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods. While rheological measurements were carried out with a rheometer, bulk conductivities were measured with a pico-ammeter. In addition, the morphology of biocomposite films was determined via field emission scanning electron microscopy. The nanomechanical properties of biocomposite film was investigated via XPM analyses. According to the rheological measurements and nanoindentation hardness results, it is understood that as the amount of carbonized waste rubber increases, flexibility decreases and harder and brittle structures are observed in biocomposite films. The electrical measurement results showed that electrical conductivity increased as the amount of carbonized waste rubber increased. When all the results obtained were evaluated, it could be concluded that biocomposite films obtained by increasing the electrical conductivity and hardness of PVA can be used in the electronics industry.

Lignin, a lignocellulosic polymer material, is an important active ingredient for the high-value use of renewable resources. Thus, policies for the recovery and high value-added use of renewable lignocellulosic biomass are a realistic engineering approach to address concerns such as the climate and energy crisis. In this work, the mechanical properties, thermal stability and morphology of cellulose/lignin nanocomposites were studied. Nanocomposite films containing different proportions of lignin (2.5%, 5%, 10% and 20%) were prepared. Thermal properties were assessed via thermogravimetric analysis and differential scanning calorimetry, mechanical properties via tensile test and morphological properties via scanning electron microscopy techniques. It was observed that nanolignin and nanocellulose structures are compatible with each other and depending on the main degradation temperature, the thermal stability of 2.5% lignin-containing nanocomposites is higher than that of other composites. From the results obtained, it was determined that the nanocomposite film containing 2.5% nanolignin had high thermal stability, mechanical strength and suitable morphological structure compared to other samples.