A weak interfacial binding of lignin in synthetic polymer composites leads to unsatisfactory mechanical properties, which limit their application prospects. In the present work, polystyrene (PS) and poly (butyl methacrylate) (PBMA) nanocomposites with lignin nanoparticles (LNPs) are produced by simply melting polymeric latex dispersions resulting from the radical polymerization of oil-in-water Pickering emulsions , stabilized by hybrid LNPs coated with chitosan and glucose oxidase. Through the formation of viscous polymer melts, the hybrid LNPs were finally evenly dispersed within the polymeric matrices, which gave the polymeric nanocomposites a significantly improved tensile strength without affecting their elasticity compared to pure PS and PBMA. Consequently, the composite materials reinforced with 15% by weight of the hybrid particles showed an improvement in toughness by a factor of 3.5 and 15 compared to those of the corresponding pure PS and PBMA. In addition, the presence of the hybrid particles gave the nanocomposites commendable UV-blocking and antioxidant properties, which are relevant for protective packaging and coating applications. Overall, our results show a new and environmentally friendly way with excellent material economy (total mass yield up to 91%) for the production of strong and transparent polymeric nanocomposites, which with up to 30 wt. Polymer composites for a wide range of applications.