The widespread use of plastics in modern society has led to a growing accumulation of polymer waste, necessitating for urgent waste management. A major challenge in mechanical recycling lies in the poor physical properties of unsorted polymer blends, which significantly limit their reuse. This issue stems from thermodynamic immiscibility and weak interfacial adhesion between different polymers. To address this, the goal of this project is to develop a new generation of additives that enhances adhesion between different types of plastics, such as polyethylene (PE), polypropylene (PP) and polystyrene (PS), by mechanically interlocking the polymer phases. These networks will be designed using thermally robust, catalyst-free, and industrially applicable dynamic chemistries. The first approach will involve the use of dynamic covalent networks, while the second one is using a supramolecular approach. A comparative study will be conducted to evaluate the two key approaches in reinforcing and compatibilizing commodity thermoplastics.