New breakthrough in Polycarbonate Flame Retardant Technology

A new type of modified nano-carbon black (MCB) flame-retardant polycarbonate (PC) composite has significantly enhanced the flame retardancy and safety of PC while maintaining its excellent mechanical properties, providing new possibilities for expanding the applications of PC materials.

In the field of materials science, polycarbonate (PC) is widely used in various industries such as construction, medical devices, and electronics due to its outstanding thermal stability, light transmittance, chemical resistance, and mechanical properties. However, unmodified PC tends to produce droplets and release a large amount of toxic gases during combustion, which limits its application in scenarios with high safety requirements.

The expert team prepared modified polycarbonate with excellent flame retardant and mechanical properties by blending PC resin with modified nano-carbon black grafted with silicone oil via the melt blending method. Experimental results show that with an MCB doping amount of 2.0%, the prepared PC composite exhibits the best overall performance. Compared to unmodified PC, the limiting oxygen index (LOI) of the new composite increased by 30%, with almost no molten dripping during combustion. The material's flame retardancy reached the V-0 rating. The peak heat release rate (HRR) decreased by 57.5% to only 240 kW/m². The peak smoke release rate decreased by 40.9%, and the peak production rates of CO₂ and CO decreased by 60.5% and 61.0%, respectively. Furthermore, as the content of silicone-oil-grafted nano-carbon black increases, the tensile strength of the PC composites improves, while the elongation at break decreases. Nonetheless, the overall mechanical properties remain at a relatively high level. This indicates that the modified nano-MCB has good compatibility with PC, and the material's mechanical properties are not significantly compromised.

Overall, this innovation not only significantly enhances the flame retardant performance of PC materials and reduces the release of toxic gases during combustion but also maintains the excellent mechanical properties of PC, making its applications in fields such as construction, medical devices, and electronics safer and more reliable.