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• A 3D boron nitride skeleton was fabricated by the ice template method. • The thick skeleton layer provides a more efficient heat transfer path. • The synergistic flame retardant mechanism of boron nitride and ammonium polyphosphate was revealed. • The char residue left in the combustion can support weights more than 1100 times of its own mass. Epoxy (EP) is widely used in the field of high-speed communication and microelectronics. However, its poor thermal conductivity and high flammability bury the hidden danger of fire accident. In this work, the hexagonal born nitride (h-BN) combined with ammonium polyphosphate (APP) constructs a three-dimensional skeleton (3D-BN) via bidirectional freezing technology. The 3D-BN skeleton is immersed into the EP matrix to obtain the EP/3D-BN composite, which is endowed with high thermal conductivity and flame retardancy. When the loading of hexagonal born nitride (h-BN) is 9.1 vol%, the thermal conductivity of EP/3D-BN 3 composite reaches 1.67 W m−1 K−1, which is increased by 944 % compared with that of the control EP. The peak heat release rate (PHRR) and total heat release (THR) of EP/3D-BN 3 are significantly reduced by 54 % and 34 % respectively. This EP/3D-BN composite provides potential applications toward the industrial production for microelectronic devices. In this work, the hexagonal born nitride (h-BN) combined with ammonium polyphosphate (APP) constructs a three-dimensional scaffold (3D-BN) via bidirectional freezing technology. The 3D-BN scaffold is immersed into the epoxy (EP) matrix to obtain the EP/3D-BN composite, which is endowed with high thermal conductivity and flame retardancy. [Display omitted] [ABSTRACT FROM AUTHOR]

Introducing bio-based acid sources into the cellulose lumens is an effective way to enhance the flame retardant of wooden products. The wood was delignified at first and then phytic acid (PA) was adsorbed solely into the vessels of the wood. With only 8.0 wt% addition of PA, the highly flame retardant wood was obtained. The limiting oxygen index (LOI) of the treated sample was reached 37.2%, the sample also passed the V-0 grade in the UL-94 vertical burning test, and in the CONE test, the total heat release was reduced by 71.3% compared to that of the Natural wood sample. The flame retardant mechanism was probed and summarized as capture of the flaming radicals, the synergistic promotion on charring and suppression on heat and smoke release. After hot-pressing, the flame-retardant treated wood sample exhibited much enhanced mechanical properties, its tensile strength went up to 138 MPa and its bending strength reached 213 MPa, which are 6 times and 7.8 times higher than that of the Natural wood, respectively. This work provided a simple and environmental-friendly method to prepare flame retardant wood for furniture applications. [Display omitted] • Flame retardant wood is prepared by delignification and adsorption of phytic acid. • The treated wood obtains 6–7 times strength enhancement after hot-pressing. • Limited oxygen index of the treated wood is 37.2, it also passes UL-94 V-0 grade. • The total heat release of the treated wood in burning is reduced by 71.3%. • Phytic acid immertion in wood brings little color change and mechanical worsening. [ABSTRACT FROM AUTHOR]

A self-healing coating containing polyethyleneimine (PEI)/ammonium polyphosphate (APP) polyelectrolyte complex was successfully prepared, and then was deposited on flexible polyurethane foam (FPUF) in association with graphene oxide (GO) via a simple dip-nip process to improve the flame retardancy and mechanical property. The vertical burning test revealed that the FPUF coated with PEI/APP and GO extinguished immediately after removing the igniter. The cone calorimeter results demonstrated that the coating effectively reduced the peak heat release rate by 63.8%. The char analysis suggested that PEI/APP formed an intumescent char structure and released inert gases, whilst GO improved the compactness of the char layer. Furthermore, the compressive strength of the coated foam sample was increased by 175.0% compared to that of the control FPUF sample. The mechanical properties analysis and morphology observation proved that the PEI/APP-GO coating had self-healing ability. This unique intrinsic self-healing coating provides a new opportunity for imparting flame retardancy and excellent mechanical property to foam materials used in many commercial cases. [Display omitted] • PEI/APP-rGO was coated on the foam via a dip-nip process. • The coating improved the flame retardancy and eliminated the melt dripping. • The coating significantly increased the mechanical properties. • The coating showed excellent durability and self-healing ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A fully bio-based multifunctional additive (PA@CHTM) was synthesized. • PA@CHTM improved flame retardancy, mechanical properties and UV resistance of PLA. • The addition of bio-based PA@CHTM can accelerate the degradation of PLA. • A biodegradable, UV resistant and flame retardant polymer composite was fabricated. Despite the advantages of biological compatibility and high transparency, there are still some drawbacks for Poly(lactic acid) (PLA) such as highly flammability and poor ultraviolet resistance. Herein, a fully bio-based additive (PA@CHTM) with a core–shell structure is synthesized by chitosan microspheres and phytic acids. The introduction of PA@CHTM simultaneously improves the mechanical properties, flame retardancy, and UV-blocking performance of PLA, accompanied by an accelerated degradation capacity in soil. By the presence of 9 wt% PA@CHTM in the PLA composite sample, the limiting oxygen index value is increased from 18.2% to 29.6%, and the UL-94 test grade is improved to V-0. The tensile strength is well maintained and Young's modulus is sharply increased for PLA/PA@CHTM composites. Moreover, the photoaging process of PLA can be significantly delayed due to the excellent free radical quenching capacity of PA@CHTM. Only less than 10% UV light can be penetrated for the PLA/9%PA@CHTM sample, and the ultraviolet protection factor is increased from 0.77 of control PLA to 30.07. More importantly, the addition of PA@CHTM can accelerate the degradation of PLA, which is of significance for biodegradable materials. This work firstly provides a green strategy to fabricate fully bio-based polymer composites with high performance, long service life, and rapid degradation in soil. [ABSTRACT FROM AUTHOR]

• Coating of uniformly dispersed LDHs were prepared on the surface of cotton fabric. • The coating exhibited strong smoke suppression effect. • The hydrophobic durability and oil-water separation properties of cotton are evaluated. In order to improve flame retardancy and soiling resistance of cotton fabric, a safe coating was fabricated on its surface. At first dopamine was polymerized on the cotton surface to be polydopamine (PDA), and then layered double hydroxides (LDHs) grew in situ on the platform of PDA by the coordination of catechol groups and metal ions. Cone calorimetry test results showed the coating reduced heat and smoke release during burning. Most important, more than 94% smoke was suppressed by the PDA-LDHs coating. Little cotton left after combustion but more than 10.2% of char was remained for the treated fabric by PDA-LDHs. On the other hand further covered by polydimethylsiloxane (PDMS), the treated cotton exhibited enhanced resistance to soiling and became more durable. For more than 96% oil/water separation efficiency, the treated cotton fabric can be expected to be an ideal filtration material. [ABSTRACT FROM AUTHOR]