Bioinspired, Highly Adhesive, Nanostructured Polymeric Coatings for Superhydrophobic Fire-Extinguishing Thermal Insulation Foam

Abstract

Lightweight polymeric foam is highly attractive as thermal insulation materials for energy-saving buildings but is plagued by its inherent flammability. Fire-retardant coatings are suggested as an effective means to solve this problem. However, most of the existing fire-retardant coatings suffer from poor interfacial adhesion to polymeric foam during use. In nature, snails and tree frogs exhibit strong adhesion to a variety of surfaces by interfacial hydrogen-bonding and mechanical interlocking, respectively. Inspired by their adhesion mechanisms, we herein rationally design fire-retardant polymeric coatings with phase-separated micro/nanostructures via a facile radical copolymerization of hydroxyethyl acrylate (HEA) and sodium vinylsulfonate (VS). The resultant waterborne poly(VSco-HEA) copolymers exhibit strong interfacial adhesion to rigid polyurethane (PU) foam and other substrates, better than most of the current adhesives because of the combination of interfacial hydrogen-bonding and mechanical interlocking. Besides a superhydrophobic feature, the poly(VS-co-HEA)-coated PU foam can self-extinguish a flame, exhibiting a desired V-0 rating during vertical burning and low heat and smoke release due to its high charring capability, which is superior to its previous counterparts. Moreover, the foam thermal insulation is well-preserved and agrees well with theoretical calculations. This work offers a facile biomimetic strategy for creating advanced adhesive fire-retardant polymeric coatings for many flammable substrates.

Tough, Instant, and Repeatable Adhesion of Self‐Healable Elastomers to Diverse Soft and Hard Surfaces

“…Neither of these two types can perfectly integrate tough adhesion and reusability due to their intrinsic drawbacks. Temporary elastomer adhesives can directly adhere to the solid surfaces through reversible interactions, as exemplified by Van der Waals interaction, [ 25 ] hydrogen bonding, [ 26 ] hydrophobic interaction, [ 27 ] reversible covalent bonds, [ 28 , 29 ] and polymer entanglements, [ 30 ] etc. Such adhesives usually show rapid, immediate, and repeatable adhesion, whereas the adhesion toughness is low because of limited hysteresis of the bulk during interfacial separation.…”

Flame Retardancy, Thermal and Mechanical Properties of Novel Intumescent Flame Retardant/MXene/Poly(Vinyl Alcohol) Nanocomposites

“…Each specimen, with dimensions of 100 mm × 100 mm × 5 mm, was packaged in aluminum foil and radiated horizontally to an external heat flux of 35 kW/m 2 . The fire performance index is recognized to be a reliable indicator of a polymer’s flammability [ 28 ] which is shown in Equation (1). where, is the time to ignition; is the time to pHRR.…”

Superinsulating BNNS/PVA Composite Aerogels with High Solar Reflectance for Energy-Efficient Buildings

“…Silica aerogels exhibit an ultralow TC of ∼ 20 mW m −1 K −1 , but the mechanical brittleness and processing complexity limit their applications in niche fields such as aerospace vehicles [ 12 – 14 ]. In contrast to silica aerogels, polymer aerogels exhibit superior mechanical properties [ 15 ], making them promising candidates for practical insulation for building envelopes [ 16 – 21 ].…”