A sustainable approach for thermoplastic composites wıth tailorable characteristics by thermokinetic hybridızation of waste cellulose and vermıculite

The thesis reveals the constitutive interactions between WC/VC and host matrices that lead to improved mechanical response along with ease of processing. The fundamental outcome of the PLA-base hybrid is the in-situ exfoliation of VC under high shear mixing which turns VC into nano-metric platelets that both ensure effective stress transfer between main reinforcement phase that is fibrous WC and micro-crack deflection in brittle PLA matrix. The findings indicated that the integration of WC and VC into PLA can enhance the Young's modulus by up to 127% and the flexural modulus by up to 137%, while maintaining the tensile strength at an optimal level.From thereon, the thesis focuses on the results achieved when similar hybridization effort is applied to ductile PP polymer with significantly different mechanical response. Presented results revealed the presence of a serious WC entanglement which governs the overall mechanical response and the inability of VC to form the PP/VC fibrils in the presence of WC. However, the mechanical response of the obtained hybrid composites was even more improved due to inherent ductility of PP. When used in the presence of high fiber content (20WC10VC) such platelets contributed significantly to tensile strength by making PP more brittle and allowing for an effective stress transfer during WC cluster debonding events. The enhancements in the PP hybrid composite were 118% for Young's modulus and 115% for flexural modulus. Furthermore, the strength of PP was increased by the hybridization of WC and VC. The flexural strength and tensile strength exhibited increases of up to 42% and 56%, respectively.The nature of this in-situ exfoliation is further evaluated where the effect of polarity difference between PLA and PP on VC interlayer region that contains crystalline water molecules. By focusing solely on VC composites arrives an important conclusion which is the formation of PP/VC fibril structures in non-polar PP matrix. Such fibrils are found to be formed of VC platelets uniformly distributed in PP fibrils occurred under extreme shear. Study proves that solely VC can enhance the Young's modulus of PP compositesby up 110% Contrarily it has been explored that although the presence of crystalline water causes a better in-situ exfoliation, it causes water evaporation from polymer surface. The study has demonstrated that the addition of VC can significantly enhance the Young's modulus of PLA composites, with an increase of up to 147%. Presented results underlined the necessity of the hybrid approach.Consequently, this thesis explores the impact of polymer type on the interaction with the fillers. It investigates the use of WC and VC in both PLA and PP composites, analyzing the resulting morphology and its influence on mechanical properties. By combining bio-based materials and natural fillers with innovative processing techniques, this research paves the way for the development of high-performance, eco-friendly composites. This thesis presents valuable insights into the potential of these green composites for various industrial applications requiring improved mechanical properties without compromising environmental responsibility.