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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]

The incorporation of biological resources for developing flame retardant is a promising approach to fabricate durable flame retardant fabrics. Herein, a novel bio-based flame retardant ammonium salt of taurine phosphonate (PTau) was successfully synthesized from taurine and grafted onto the nylon-cotton (NYCO) blend fabrics by covalent bonds. Both the flame retardancy and washing durability of PTau treated NYCO fabrics were improved significantly. The limiting oxygen index (LOI) value of PTau-NYCO fabric was increased from 18.5 % to 36.7 % and the damaged length was reduced from 30.0 cm to 5.6 cm during the vertical burning test. The flame retardancy of PTau-NYCO fabric was well preserved with the LOI value of 29.2 % after 40 laundering cycles. Cone calorimeter test indicated that the PTau-NYCO fabric decreased the peak heat release rate from 207.7 kW/m2 to 77.5 kW/m2, and the total heat release rate from 10.5 MJ/m2 to 5.6 MJ/m2, respectively, compared with that of the control NYCO fabric. Thermogravimetric analysis test showed that the char formation ability was improved for PTau-NYCO fabric with the char residue of 37.2 wt% at 800 °C. The flame retardant mechanism showed that PTau was beneficial to form the char layer and generate nonflammable gases. In general, this work proposes a feasible method to produce durable flame retardant NYCO fabrics by using taurine derivatives. [Display omitted] • The bioactive substance of taurine is an eco-friendly and sustainable resource. • Treated nylon-cotton blend fabrics showed improved flame retardancy and excellent washing durability. • The application of taurine provided an effective strategy to reduce the fire hazards of fabrics. [ABSTRACT FROM AUTHOR]

Polycarbonate (PC) is known for its high impact resistance and transparency. However, fabricating flame-retardant and scratch resistant PC without sacrificing its mechanical properties and transparency remains a great challenge. Herein, we prepared a highly transparent and fast curing coating (DA-AE) composed of imidazole-based flame-retardant curing agents (DA) and epoxy-oligosiloxane (AEOS) via imidazole-induced anionic polymerization. The curing time of DA-AE coating was only 8 min at 130 °C. The presence of the coating significantly improved the flame retardancy and scratch resistance of PC films. In contrast to the uncoated PC films, the PC/DA-AE sample self-extinguished within 1.2 s in the vertical burning test and achieved a limiting oxygen index of 27.1 %. In the cone calorimeter test, the PC/DA-AE sample exhibited a notable 49.1 % reduction in the peak heat release rate compared to that of the PC films. Additionally, the pencil hardness of PC/DA-AE-2 was increased to 6H from 2B of the control PC film. The coating exhibited good adhesion to the PC substrate and achieved the highest grade in the cross-cut test without any surface pre-treatment. Remarkably, the coating showed strong chemical and mechanical stability during tests of wiping cycles with different solvents and bending cycles. This work provided a simple and efficient strategy for large-scale producing transparent flame-retardant and scratch resistant PC films. [Display omitted] • A transparent and flame-retardant coating (DA-AE) was prepared via imidazole-induced anionic polymerization. • The DA-AE coating simultaneously improved the surface hardness and flame retardancy of PC films. • The coated PC films showed high transparency, solvent wiping resistance and good flexibility. [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]

In this work, a fully bio-based multi-functional intumescent flame retardant coating containing ε-polylysine (ε-PL), 5-hydroxymethylfurfural (5-HMF), and phytic acid (PA) was successfully constructed on the polyethylene terephthalate (PET) fabrics via a facile one-pot dip-pad-dry process. The introduction of the coating significantly improved the fire performance of the fabric. The treated PET fabric had a limiting oxygen index value of 28.1 %, and was free of molten drops in the vertical flammable test. The flame retardant mechanism analysis indicated that the three components in flame retardant coating formed intact char layers during combustion which hindered the transfer of oxygen/heat and inhibited the generation of flammable volatiles. The treated PET fabric also exhibited better antibacterial ability against E. coli and S.aureus compared to the control sample. Besides, the breaking strength and the elongation at the break of the treated PET fabric were slightly improved. This work provides a facile and sustainable strategy to fabricate PET fabrics with flame retardancy and anti-dripping properties. [Display omitted] • A fully bio-based flame retardant and antibacterial coating was constructed. • The coated PET fabrics showed self-extinguishing and anti-dripping properties. • The synergistic flame retardant mechanism was evaluated. [ABSTRACT FROM AUTHOR]