(751b) Fabrication of Polystyrene/Graphene Quantum Dots Nanocomposites for Enhanced Flame Retardant Properties Via Pickering Emulsion Polymerization

Significant improvements in thermal and flame retardant properties of polymeric materials holds tremendous promise for fire safety materials. Carbon-based nanoparticles have low cytotoxicity, chemical inertness, cost-effectiveness, and biocompatibility. In the present work, an alkyl modified graphene quantum dots (C-GQDs) were deposited on a polystyrene (PS) sphere (PS/C-GQDs) for reducing its fire hazards. The PS/C-GQDs nanocomposites were fabricated via Pickering emulsion polymerization directly in the presence of the amphiphilic C-GQDs was as sole stabilizer during the polymerization process. Morphological characterization by SEM suggested the successful preparation of C-GQDs stabilized PS colloidal particles, and C-GQDs layer was wrapped on the surface of PS microspheres. It could provide a potential pathway to introduce flame retardant to polymeric materials directly and efficiently. Enhanced thermal stability and flame retardancy were obtained for PS/C-GQDs which synthesized with 2% C-GQDs in aqueous phase. There is a decrease ca. 35% in peak heat release rate compared to neat PS, respectively. The enhanced fire-retardant properties should be ascribed to the barrier of assembled C-GQDs on sphere surface. And the incorporation of C-GQDs could remarkably improve the stability of char layer. And the char layer served as an efficient insulating barrier to impeded the permeation of heat and the escape of pyrolysis volatile products. Thus, this work paves a potential pathway to design efficient assembled fire-retardant systems for fire safety.