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High‐performance polymers have proliferated in modern society across a variety of industries because of their low density, good chemical stability, and superior mechanical properties. However, while polymers are widely applied, frequent fire disasters induced by their intrinsic flammability have caused massive impacts on human beings, the economy, and the environment. Supramolecular chemistry has recently been intensively researched to provide fire retardancy for polymers via the physical barrier and char‐catalyzing effects of supramolecular aggregates. In parallel, the noncovalent interactions between supramolecular and polymer chains, such as hydrogen bonding, π–π interactions, metal–ligand coordination, and synergistic interactions, can endow the matrix with enhanced mechanical strength. This makes it possible to integrate physical–chemical properties and noncovalent interactions into one supramolecular aggregate‐based high‐performance polymeric system on demand. However, fulfilling these promises needs more research. Here, we provide an overview of the latest research advances of fire‐retardant and high‐strength polymer materials based on supramolecular structures and interactions of aggregates. This work reviews their conceptual design, characterization, modification principles, performances, applications, and mechanisms. Finally, development challenges and perspectives on future research are also discussed. [ABSTRACT FROM AUTHOR]

Biodegradable polymeric materials with high strength and outstanding toughness are necessary for real‐world applications in the fields of electronics, electrics, and packaging. Unfortunately, such performance portfolios in polymers remain challenging to achieve due to their different governing mechanisms. Inspired by the hydrogen‐bond (H‐bond) cross‐linking structure of spider silk, herein, strong and tough poly(vinyl alcohol) (PVA) composites with β‐cyclodextrin as a cross‐linker are developed. Benefiting from the H‐bond cross‐linking effect, the addition of 1.0 wt% of β‐cyclodextrin enables PVA to achieve a high tensile strength of 136.5 MPa, and a high elastic modulus of 3.0 GPa, in combination with a good toughness of 82.1 MJ m−3. In addition, the presence of β‐cyclodextrin improves the biodegradability of PVA composite by decreasing its crystalline size. Furthermore, PVA/β‐cyclodextrin composite combined with MXene has great potential as a sensor material for humidity and strain detection. This proof‐of‐concept opens numerous opportunities to create strong, tough, and biodegradable polymers for packing and sensing applications. [ABSTRACT FROM AUTHOR]

Recently, soaring developments in microelectronics raise an urgent demand for thermal management materials to tackle their "overheating" concerns. Polymer nanocomposites are promising candidates but often suffer from their inability of mass production, high‐cost, poor mechanical robustness, and even flammability. Hence, it is desirable to scalably fabricate low‐cost, robust polymeric nanocomposites that are highly thermally conductive and fire‐retardant to ensure safe and efficient thermal management. Herein, the scalable production of nacre‐like anisotropic nanocomposite films using the layer‐by‐layer assembly of phenylphosphonic acid@graphene nanoplatelets (PPA@GNPs)‐poly(vinyl alcohol) (PVA) layer and GNPs layers, is demonstrated. The PPA serves as interfacial modifiers and fire retardants for flammable PVA (film‐forming agent) and GNPs (inexpensive conductive nanofillers) via hydrogen‐bonding and π–π stacking. The resultant nanocomposite exhibits a high flexibility, high tensile strength of 259 MPa, and an ultrahigh in‐plane thermal conductivity of 82.4 W m‐1 K‐1, making it effectively cool smartphone and high‐power light emitting diode modules, outperforming commercial tinfoil counterparts. Moreover, the as‐designed nanocomposites are intrinsically fire‐retardant and can shield electromagnetic interference. This work offers a general strategy for mass production of thermally conductive nanocomposites holding great promise as thermal management materials in electronic, military, and aerospace fields. [ABSTRACT FROM AUTHOR]

Novel iron hexamethylenediaminetetrakis-(methylenephosphonate) (Fe-HDTMP)-reduced graphene oxide (Fe-rGO) hybrids were prepared by in situ immobilization of Fe-HDTMP nanoparticles and the reduction of graphene oxide via a hydrothermal strategy. Fe-rGO modification of epoxy resin (EP) improved mechanical properties, flame retardancy, smoke suppression, and thermal stability by combination with flame retardant elements (i.e. Fe, N, and P) and graphene nanoplatelets. The incorporation of 1% Fe-rGO increased the impact strength and storage modulus of EP by 19.2, and 27.9%, respectively. Additionally, the incorporation of 5% Fe-rGO helped EP/5Fe-rGO achieve UL-94 V0 rating with a limiting oxygen index of 30.5%. Compared to untreated EP, the modified EP exhibited 68.2% lower release of total smoke, 54.5% decreased peak CO production rate, 66.3% lower total heat release, and 47.7% reduced peak heat release rate of EP/5Fe-rGO. In addition, the glass-transition temperature of EP/Fe-rGO nanocomposite was maintained at a high level. The improved fire safety performance of EP/2Fe-rGO nanocomposite was due to the catalyzing carbonization effect, the release of inert compounds of Fe-rGO in condensed and gas phases, and the barrier effect of graphene. [ABSTRACT FROM AUTHOR]

A novel phosphorus-nitrogen flame retardant, nano zirconium amino- tris -(methylenephosphonate) (Zr-AMP), successfully synthesized by allowing amino trimethylene phosphonic acid (AMP) to react with ZrOCl·8H 2 O, was incorporated into rigid polyurethane (RPU) foam with expandable graphite (EG) to prepare flame retarded composites. A synergistic effect between nano Zr-AMP and EG on flame retarded and physical-mechanical properties of RPU foam was observed. The RPU foam containing 3 wt% nano Zr-AMP and 12 wt% EG (RPU/12EG/3Zr-AMP) achieved a UL-94 V0 rating with a limiting oxygen index of 30.5%. RPU/12EG/3Zr-AMP showed a 74.4% reduction of peak heat release rate relative to untreated RPU foam. Furthermore, RPU/12EG/3Zr-AMP possessed lower thermal conductivity compared with the RPU foam with 15 wt% EG (RPU/15EG), while the compressive strength of RPU/12EG/3Zr-AMP was enhanced by 40% compared with the one of the latter. The thermogravimetric analysis showed that the simultaneous addition of nano Zr-AMP and EG had a positive impact on improving the char yield and thermal stability of RPU foam. Image 1 • Zr-AMP was synthesized and evaluated as a novel phosphorus and nitrogen-containing flame retardant for RPU foam. • Zr-AMP nanoparticles improved compressive strength, thermal stability and flame retardancy of RPU foam. • Zr-AMP nanoparticles and EG showed good synergistic effect on flame-retardant and physico-mechanical properties in RPU foam. [ABSTRACT FROM AUTHOR]