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Highly transparent polycarbonate (PC) has received more and more attention. However, several key issues, such as its inherent low flame-retardancy and poor scratch-resistance, are still required to be addressed. Herein, a phosphonamide-siloxane (PPA Si) hybrid coating was synthesized and coated on PC plates via sol-gel methods. The combination of PPA and Si endowed PC with excellent fire performance, the formed Si-O-Si cross-linking network provided hardness and curing capacity, and the PPA increased the flexibility of coating. The coated PC sample showed excellent flame retardancy, good scratch resistance, and high transparency. The PC/PPA-Si-3 sample with a limiting oxygen index of 28.5 % achieved a UL-94 V -0 rating. The peak heat release rate and total heat release of the coated sample were decreased by 56.2 % and 18.3 %, respectively, compared to that of the control PC sample. Meanwhile, the pencil hardness was improved from 2B of the control PC to 2H of the PC/PPA-Si-3 sample, and the coating still maintained good flexibility and adhesion even after being immersed in liquid nitrogen for 20 min. Furthermore, the effect of different ratios of phosphonamide and silicon on the flammability and physical mechanical properties of PC was also investigated. This work has offered a possible strategy to produce transparent, flame-retardant, and scratch-resistant PC plates. [Display omitted] • A transparent and flame-retardant coating was prepared via a sol-gel method. • The organic/inorganic hybrid coating improved the surface hardness of PC plates. • The coated PC showed excellent flame retardancy and good flexibility. • The coating layer formed intumescent char during combustion. [ABSTRACT FROM AUTHOR]

With the increasing requirements of eco-friendly flame retardant fabrics, fully bio-based flame retardants have attracted more and more attention. In this work, a fully bio-based flame retardant coating (PALC) was prepared by combining phytic acid and L-cysteine through ion exchange, which was then applied to nylon-cotton blends. The water contact angle (WCA) test indicates that the hydrophilicity of treated blend fabrics is significantly increased. The treated blend fabrics also exhibited excellent antibacterial property against E. coli and S. aureus. Besides, the limiting oxygen index (LOI) value of the treated blend fabric is increased to 27.2 % from 19.3 %, and the damage length is reduced to 5 cm from 30 cm. The analysis of cone calorimetry test results demonstrates that the total heat release (THR) and peak heat release rate (pHRR) values of the treated blend fabric are reduced by 62.6 % and 65.4 %, respectively, relative to CO/NY. At the same time, the PALC coating can also endow the blend fabric with smoke suppression properties. The total smoke production (TSP) and smoke production rate (SPR) values are reduced by 64.5 % and 67.6 %, respectively. The combination analysis of TG-FTIR, SEM and XPS proves that the phytic acid promotes the dense char layers forming, and L-cysteine generates non-combustible gases. This work provides an eco-friendly and organic solvent-free method for producing flame-retardant nylon/cotton blends with reduced smoke release. [Display omitted] • An organic solvent-free coating PALC was developed from phytic acid and L-cysteine. • PALC coating improved the fire performance of nylon/cotton blend fabrics. • PALC coating increased the hydrophilicity of nylon/cotton blend fabrics. • PALC treated nylon/cotton blend fabrics showed antibacterial property. • PALC acted in both gas-phase and condensed-phase during the combustion. [ABSTRACT FROM AUTHOR]