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Silicone rubber (SR), as one kind of highly valuable rubber material, has been widely used in many fields, e.g., construction, transportation, the electronics industry, automobiles, aviation, and biology, owing to its attractive properties, including high- and low-temperature resistance, weathering resistance, chemical stability, and electrical isolation, as well as transparency. Unfortunately, the inherent flammability of SR largely restricts its practical application in many fields that have high standard requirements for flame retardancy. Throughout the last decade, a series of flame-retardant strategies have been adopted which enhance the flame retardancy of SR and even enhance its other key properties, such as mechanical properties and thermal stability. This comprehensive review systematically reviewed the recent research advances in flame-retarded SR materials and summarized and introduced the up-to-date design of different types of flame retardants and their effects on flame-retardant properties and other performances of SR. In addition, the related flame-retardant mechanisms of the as-prepared flame-retardant SR materials are analyzed and presented. Moreover, key challenges associated with these various types of FRs are discussed, and future development directions are also proposed. [ABSTRACT FROM AUTHOR]

Intumescent fire-retardant coatings, which feature thinner layers and good decorative effects while significantly reducing heat transfer and air dispersion capabilities, are highly attractive for fire safety applications due to their effective prevention of material combustion and protection of materials. Particularly, the worldwide demand for improved environmental protection requirements has given rise to the production of waterborne intumescent fire-retardant polymer composite coatings, which are comparable to or provide more advantages than solvent-based intumescent fire-retardant polymer composite coatings in terms of low cost, reduced odor, and minimal environmental and health hazards. However, there is still a lack of a comprehensive and in-depth overview of waterborne intumescent fire-retardant polymer composite coatings. This review aims to systematically and comprehensively discuss the composition, the flame retardant and heat insulation mechanisms, and the practical applications of waterborne intumescent fire-retardant polymer composite coatings. Finally, some key challenges associated with waterborne intumescent fire-retardant polymer composite coatings are highlighted, following which future perspectives and opportunities are proposed. [ABSTRACT FROM AUTHOR]

Owing to their preeminent properties, including mechanical flexibility, thermal insulation, and low cost, silicone foams are widely used in industrial fields. However, flame‐induced structural failure greatly restricts their practical applications. It is challenging for flexible silicone foams to realize reliable thermal protection in thermo–mechanical–oxidative environments. Inspired by traditional pottery, a multiscale‐filler synergistic ceramifiable strategy for creating silicone foam nanocomposites with flexibility and long‐term fireproofing is proposed herein. The foam materials not only maintain mechanical flexibility and elasticity (≈2% residual strain after 1000 cycles) at a temperature range of −60–210 °C but also exhibit exceptional long‐term (>30 min) thermal insulation upon exposure to ≈1300 °C oxidative environments because of their ability to form a gradient robust porous ceramic structure. Moreover, the foam material can provide stable thermal protection for electric cables and lithium‐ion battery packs, making it one of the most reliable thermal insulation materials so far. This work broadens the applications of silicone foams in emerging fields where mechanical buffering and fireproofing are required. [ABSTRACT FROM AUTHOR]

Owing to their high sensitivity across a wide stress range, mechanical reliability, and rapid response time, flexible polymer foam piezoresistive sensors have been extensively used in various fields. The reliable application of these sensors under harsh environments, however, is severely limited by structural devastation and poor interfacial bonding between polymers and conductive nanoparticles. To address the above issues, robust MXene/CNT nanocoatings on the foam surface, where the chemical assembly of MXene nanosheets and the physical anchoring of CNTs lead to strong interfacial bonding, are designed and described, which endows foams with structural reliability and unexpected multi-functionalities without compromising their instinct properties. The optimized foam nanocomposites thus maintain outstanding wide-temperature flexibility (-60-210 °C) and elasticity (≈3% residual strain after 1000 cycles). Moreover, the nanocomposites display good sensitivity at a relatively wide stress range of 0-70% and remarkable stability under acidic and alkaline settings. Furthermore, the foams with exceptional fire resistance (UL-94 V-0 rating) can provide stable sensing behavior (over 300 cycles) even after being exposed to flames for 5 s, making them one of the most reliable sensing materials so far. Clearly, this work widens applications of flexible piezoresistive sensors based on silicone foam nanocomposites for various harsh environments., (© 2024 Wiley‐VCH GmbH.)