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To protect weathered ancient stone monuments from surface cracking and surface damage by powders, strong materials containing flexible chains are required. Herein, a facile strategy was proposed to produce hybrid octa-glycidyl polyhedral oligomeric silsesquioxane (GPOSS)-enhanced flexible siloxanes by the ring-opening reaction of GPOSS using three aminosiloxanes (bis(3-aminopropyl) terminated poly (dimethyl siloxane) (NH 2 -PDMS), 3-aminopropyltriethoxysilane (APTS), and N-(6-aminohexyl) aminopropyl trimethoxysilane (AHAPTMS). This produced three different protective materials (POSS-PDMS, POSS-APTS, and POSS-AHAPTMS) that greatly improved the weather resistance of sandstone monuments, especially their resistance to water, salt, temperature, and humidity. All three protective materials presented an adhesion of up to 2.4 MPa. The resistance of freeze-thaw aging cycles was much higher for the protected sandstone (104–133 cycles) compared with the unprotected sandstone (20 cycles). The three protective materials improved the salt weather resistance of protected sandstone (9–60 cycles) compared with unprotected sandstone (3 cycles), with the long-chain aminosiloxane AHAPTMS providing the best protection. The hydrophobicity of three protective materials on the sandstone surface was improved. Furthermore, the water absorption, water vapor permeability, pore size distribution, mechanical strength, light transmittance, and glass transition temperature (T g), were all improved. The three GPOSS-enhanced flexible siloxanes are novel and eco-friendly materials for protecting sandstone monuments. [Display omitted] • GPOSS-enhanced flexible siloxanes was synthesized by ring-opening reaction. • GPOSS-enhanced flexible siloxanes greatly improved the weather resistance of sandstone monuments. • Protected sandstones presented improved adhesion and hydrophobicity. • GPOSS-enhanced flexible siloxanes are novel and eco-friendly materials for protecting sandstone monuments. [ABSTRACT FROM AUTHOR]

To meet the requirements of fire protection and decorative properties of wood, developing transparent fireproof coatings with excellent comprehensive performance is vital. A new category of organophosphate-grafted α‑zirconium phosphate (α-ZrP) was synthesized as functional flame retardant, then in combination with melamine-formaldehyde resin prepared comprehensive transparent fireproof coatings covering fire protection, smoke suppression, anti-bacteria and weatherability. The results show that adding α-ZrP results in an effective improvement of the mechanical properties, fire protection and smoke suppression under the premise of guaranteeing the high transparency of the coatings. In particular, the MZrPPB3 sample containing a 98:2 mass ratio of phosphate ester to modified α-ZrP possesses 55.2 %, 76.2 % and 23.7 % decrement in flame spread rating, smoke density rating and equilibrium backside temperature at 900 s in comparison with MZrPPB0 sample without α-ZrP, respectively, accompanied by superior adhesion classification of 4B rating and pencil hardness of 2H rating. The efficient fire protection performance of α-ZrP-containing coatings attributes success to the high-quality intumescent char formed by the stable crosslinking and aromatic structures, as confirmed by characterization of FTIR and SEM-EDS analyses. Additionally, adding α-ZrP into the coatings confers them extraordinary weatherability rich in appearance integrity and fire protection performance after accelerated aging test. Meantime, the obtained satisfactory antibacterial property of coatings relates to the presence of α-ZrP with an antibacterial rate of up to 99.0 % for MZrPPB3 against Escherichia coli. [Display omitted] • Organophosphate-grafted α-zirconium phosphate (α-ZrP) flame retardant was synthesized. • Transparent fireproof coatings exert super mechanical properties and fire resistance. • Transparent fireproof coatings exert super weatherability for long-term fire protection. • Introduction of α-ZrP enhances antibacterial property of transparent fireproof coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] • The robust mastoid micro/nano-structures can be obtained by a two-step phase separation method. • The organic-inorganic hybrid coating possessed good mechanical durability to resist abrasion damage. • The prepared coating can maintain its superhydrophobicity after high pressure water jetting. • The prepared coating provided excellent corrosion/weather protection against corrosive medium or UV radiation. Artificial superhydrophobic coatings inspired by nature are expected to have extensive applications in several aspects of our daily lives once their poor mechanical and chemical durability is overcome. In this study, we developed a robust superhydrophobic organic-inorganic hybrid coating through the combination of fluorinated ethylene propylene (FEP) and aluminum dihydrogen phosphate (ADP) using a novel two-step phase separation method. An inorganic adhesive of ADP was introduced as a building block to enhance the structural robustness of the superhydrophobic coating. Carboxylated carbon nanotubes (C-CNTs) with good dispersibility in both water and ethanol were employed as emulsifiers to promote the liquid phase separation of FEP and ADP, which was beneficial for the formation of abundant microspheres in aqueous ethanol. After spraying and thermal treatment, the uniform mastoid micro-/nanostructures were formed on the coating surface due to the thermal phase separation of microspheres, which can provide excellent superhydrophobicity with a water contact angle of 162 ± 1.1° and a sliding angle of 5 ± 0.5°. The prepared coating can maintain its outstanding hydrophobicity even after 1000 abrasion cycles with sandpaper and upon jetting with high pressure water flow (200 kPa). Moreover, owing to the chemical inertness of the hybrid micro-/nanostructures, the prepared coating can provide a high level of corrosion protection against strong corrosive mediums as well as weather protection against UV radiation (300 W/m2). Therefore, it is believed that the robust organic-inorganic hybrid superhydrophobic coating prepared by facile phase separation method would present new avenues for expanding the practical applications of superhydrophobic coatings. [ABSTRACT FROM AUTHOR]

A facile and solvent-free strategy was developed to prepare optically transparent, mechanically robust, hydrophobic coating with excellent adhesion to the substrate. • A novel GPMS-DTDA/PFTS-based coating was synthesized through a simple sol-gel method. • The GPMS-DTDA/PFTS-based coating displays ultrahigh mechanical strength with the hardness/adhesion of 9H/5B. • The GPMS-DTDA/PFTS-based coating exhibits excellent hydrophobicity with a water contact angle of 107°. A mechanically robust, transparent, solvent-free, and self-cleaning coating (GPMS-DTDA/PFTS) was fabricated based on the co-hydrolysis/condensation of the Dibutyltin dilaurate, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (curing agent), while the different amount of 1H,1H,2H,2H-Perfluorodecyltrimethoxysilane were added to the system to reduce the surface energy of the coating. The morphology and properties of the polysiloxane-based coating were characterized by SEM, FTIR, UV–vis-NIR. The as-synthesized GPMS-DTDA/PFTS-based coating displays excellent performance with the hardness of 8H, superior adhesion (5B), high transmittance (95.2 %), hydrophobicity (CA: 107°) as well as outstanding properties of self-cleaning and weather resistance. [ABSTRACT FROM AUTHOR]