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Covalent and defect‐free surface‐grafted solid lubricating chains that can impart “liquid‐like” slippery behavior have proven advantageous over lubricant‐infused and textured anti‐wetting surfaces. Herein, the co‐hydrolysis and co‐condensation of a mixture of organosilanes followed by the epoxy‐amine ring opening reaction at the interface results in a highly robust, transparent, and “liquid‐like” solid slippery omniphobic coating (LL‐OSC). The presence of the epoxy‐terminated organosilane a) acts as a molecular spacer in between the low‐surface energy, rigid fluorine terminated silane and b) provides “reactive” epoxy groups for covalent binding to a pre‐functionalized amine surface for potential applicability in droplet transport and manipulation, diagnostics, etc. LL‐OSC exhibits resistance to both solid and liquid abrasions such as sandpaper abrasions, prolonged UV irradiation, DI water and high temperature (30 days), and submersion in chemically contaminated aqueous solutions. This is the first report of a hemocompatible solid slippery coating for inhibiting platelet adhesion, thus, paving way for blood‐contacting medical device applications. The LL‐OSC exhibits remarkable cytocompatibility, repellence to plasma protein, and cells and prevents biofilm formation. Additionally, the substrate‐independent LL‐OSC can be applied onto metals and polymers. This study envisions that the reported durable, solid slippery coating will find widespread applicability in hospital settings, electronic devices, etc. [ABSTRACT FROM AUTHOR]

Controlled tailoring of mechanical property and wettability is important for designing various functional materials. The integration of these characteristics with waste materials is immensely challenging to achieve, however, it can provide sustainable solutions to combat relevant environmental pollutions and other relevant challenges. Here, the strategic conversion of discarded and valueless waste paper into functional products has been introduced following a catalyst‐free chemical approach to tailor both the mechanical property and water wettability at ambient conditions for sustainable waste management and controlling the relevant environmental pollution. In the current design, the controlled and appropriate silanization of waste paper allowed to modulate both the a) porosity and b) compressive modulus of the paper‐derived sponges. Further, the association of 1,4‐conjugate addition reaction between amine and acrylate groups allowed to obtain an unconventional waste paper‐derived chemically 'reactive' sponge. The appropriate covalent modification of the residual reactive acrylate groups with selected alkylamines at ambient conditions provided a facile basis to tailor the water wettability from moderate hydrophobicity, adhesive superhydrophobicity to non‐adhesive superhydrophobicity. The embedded superhydrophobicity in the waste paper‐derived sponge was capable of sustaining large physical deformations, severe physical abrasions, prolonged exposure to harsh aqueous conditions, etc. Further, the waste paper‐derived, extremely water‐repellent sponges and membranes were successfully extended for proof‐of‐concept demonstration of a practically relevant outdoor application, where the repetitive remediation of oil spillages has been demonstrated following both selective absorption (25 times) of oils and gravity‐driven filtration‐based (50 times) separation of oils from oil/water mixtures at different harsh aqueous scenarios. [ABSTRACT FROM AUTHOR]

In the past, bio‐inspired extreme water repellent property has been strategically embedded on commercially available sponges for developing selective oil absorbents. However, most of the reported materials lack physical and chemical durability, limiting their applicability at practically harsh settings. Herein, a stable dispersion of polymeric nanocomplexes was exploited to achieve a chemically reactive coating on the highly compressible melamine foam. A superhydrophobic melamine foam (SMF) was achieved after post‐covalent modification of the reactive coating through 1,4‐conjugate addition reaction at ambient conditions. The durability of the embedded extreme water repellent property in the as‐modified melamine foam has been elaborately demonstrated through exposing it to severe physical manipulations, chemically harsh aqueous media including pH 1, pH 12, surfactant contaminated water, river water, seawater and prolonged UV irradiation. Thus, the highly tolerant SMF was utilized as an efficient oil absorbent wherein oils of varying densities could be selectively recovered from an oil/water interface with high (e.g., 137 g g−1 for chloroform and 83 g g−1 for diesel) oil absorption capacity. Moreover, the selective oil absorption capacity of the as‐synthesized material remained unaffected at practically relevant severe chemical and physical settings, and the extreme water repellency of the material remained unaltered even after repetitive (at least 50 cycles) use for oil/water separation. [ABSTRACT FROM AUTHOR]