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Plant protein‐based adhesives are gaining traction owing to their low cost and eco‐friendliness. However, achieving flame retardancy and long‐term water resistance in them under room‐temperature curing conditions remains a challenge due to the hydrophilicity and low reactivity of plant proteins. Herein, a novel adhesive synthesized from soybean meal (SM), activated sodium alginate (aSA), nano‐hydroxyapatite (nHA), and polyamidoamine‐epichlorohydrin (PAE) resin addresses this challenge. aSA as a reactive bio‐based cross‐linker formed covalent cross‐linking structures with SM matrix at room temperature, while the nHA‐induced biomineralization and PAE‐constructed supramolecular cross‐linking promote water drainage from the adhesive, preventing water erosion of the adhesive structure. The developed adhesive shows versatility across multiple substrates, with its wet shear strength on wood reaching 0.76 MPa, surpassing that of the commercial aldehyde‐based adhesive. The adhesive is effective over a wide temperature range from room temperature to 150 °C due to the reactivity of the PAE resin above 60 °C. Moreover, it exhibits excellent flame retardancy (limiting oxygen index of 31.2%) owing to its dense structure and the abundance of N‐containing and P‐containing components. This work is expected to break the monopoly of petroleum‐based adhesives in the realm of room‐temperature adhesives. [ABSTRACT FROM AUTHOR]

High-temperature adhesives find extensive application in diverse domains, encompassing repairs, production processes, and material joining. However, achieving their curing at ambient temperatures remains a formidable challenge due to the inherent requirement of elevated temperatures, typically exceeding 500 °C, for the curing reaction. To overcome this limitation, in this study, we developed a distinctive inorganic phosphate-based composite adhesive by incorporating dual-functional calcium monoaluminate (CA) into a traditional adhesive blend comprising Al(H2PO4)3 and MgO. This distinctive approach significantly diminishes the curing temperature, enabling it to occur at room temperature. Firstly, CA's facile hydration reaction effectively scavenges surrounding water molecules, thereby accelerating the dehydration curing process of Al(H2PO4)3. Secondly, as hydration is an exothermic process, it locally generates heat around the Al(H2PO4)3, fostering optimal conditions for its curing reaction. Moreover, the adhesive's strength is substantially bolstered through the strategic inclusion of Nano-Al2O3 (enhancing the availability of reaction sites) and Nano-SiO2 (improving overall stability). As a demonstration, the adhesive formulation with added CA containing 2% Nano-Al2O3 and 2% Nano-SiO2 achieved a remarkable tensile strength of 32.48 MPa at room temperature, underscoring its potential as an efficient solution for various practical adhesive applications. The adhesive prepared in this study harnesses the hydration properties of CA to absorb moisture and release substantial heat, introducing a novel method for ambient temperature curing. This development promises to broaden its applications in refractory materials, coatings, and equipment repair. [ABSTRACT FROM AUTHOR]

Specialized epoxy resin, capable of achieving room-temperature profound curing and sustaining prolonged exposure to high-temperature environments, stands as a pivotal material in modern high-end manufacturing sectors including aerospace, marine equipment fabrication, machinery production, and the electronics industry. Herein, a silicon-hybridized epoxy resin, amenable to room-temperature curing and designed for high-temperature applications, was synthesized using a sol–gel methodology with silicate esters and silane coupling agents serving as silicon sources. Resin characterization indicates a uniform distribution of silicon elements in the obtained silicon hybrid epoxy resin. In comparison to the non-hybridized epoxy resin, notable improvements are observed in room-temperature curing performance, heat resistance, and mechanical strength. [ABSTRACT FROM AUTHOR]

High-temperature adhesives find extensive application in diverse domains, encompassing repairs, production processes, and material joining. However, achieving their curing at ambient temperatures remains a formidable challenge due to the inherent requirement of elevated temperatures, typically exceeding 500 °C, for the curing reaction. To overcome this limitation, in this study, we developed a distinctive inorganic phosphate-based composite adhesive by incorporating dual-functional calcium monoaluminate (CA) into a traditional adhesive blend comprising Al(H2PO4)3 and MgO. This distinctive approach significantly diminishes the curing temperature, enabling it to occur at room temperature. Firstly, CA’s facile hydration reaction effectively scavenges surrounding water molecules, thereby accelerating the dehydration curing process of Al(H2PO4)3. Secondly, as hydration is an exothermic process, it locally generates heat around the Al(H2PO4)3, fostering optimal conditions for its curing reaction. Moreover, the adhesive’s strength is substantially bolstered through the strategic inclusion of Nano-Al2O3 (enhancing the availability of reaction sites) and Nano-SiO2 (improving overall stability). As a demonstration, the adhesive formulation with added CA containing 2% Nano-Al2O3 and 2% Nano-SiO2 achieved a remarkable tensile strength of 32.48 MPa at room temperature, underscoring its potential as an efficient solution for various practical adhesive applications. The adhesive prepared in this study harnesses the hydration properties of CA to absorb moisture and release substantial heat, introducing a novel method for ambient temperature curing. This development promises to broaden its applications in refractory materials, coatings, and equipment repair.

Specialized epoxy resin, capable of achieving room-temperature profound curing and sustaining prolonged exposure to high-temperature environments, stands as a pivotal material in modern high-end manufacturing sectors including aerospace, marine equipment fabrication, machinery production, and the electronics industry. Herein, a silicon-hybridized epoxy resin, amenable to room-temperature curing and designed for high-temperature applications, was synthesized using a sol–gel methodology with silicate esters and silane coupling agents serving as silicon sources. Resin characterization indicates a uniform distribution of silicon elements in the obtained silicon hybrid epoxy resin. In comparison to the non-hybridized epoxy resin, notable improvements are observed in room-temperature curing performance, heat resistance, and mechanical strength.

The glass transition temperature (Tg) of room-temperature curing epoxy adhesives is limited by the temperature used during curing. It is already known that the excess of epoxy groups can undergo a homopolymerization reaction initiated by tertiary amines at elevated temperatures, resulting in an increase in Tg. However, there is no evidence of this reaction occurring at room temperature. In the present work, the influence of formulation stoichiometry on Tg and mechanical properties was investigated. Dynamomechanical, rheological and mechanical properties of epoxy adhesives were determined by DSC, DMA, rheometer and tensile and shear strength testing. It has been probed that an excess of epoxy resin combined with a complex curing system composed of a primary amine, a polymercaptan and a tertiary amine leads to an increase in Tg up to 70 °C due to the homopolymerization reaction that takes place at room temperature. However, as the excess of epoxy resin is increased, gel time becomes slower. Regarding mechanical properties, it has been proven that an excess of epoxy resin provides a tighter and tougher material but maintains flexibility of the stoichiometric formulation, which is meant to enhance the resistance to impact-type forces, thermal shock and thermal cycling. [ABSTRACT FROM AUTHOR]

An acrylic binder with excellent physical properties is prepared using copolymer of methyl methacrylate (MMA) and butyl acrylate monomer (BAM), 2‐hydroxyethyl methacrylate (2‐HEMA), 3‐(trimethoxysilyl)propyl methacrylate (TMSPMA), and additives. The obtained acrylic resins are subjected to a redox initiator system (ROIS) for room temperature curing. The effects of the TMSPMA concentration and [acryl‐copolymer]/[2‐HEMA] ratio on backbone content are studied in terms of traffic marking paint. The mechanical and morphological properties are thoroughly evaluated using universal testing machine (UTM), UV spectrum, and SEM. With increasing TMSPMA content, the adhesive strength and transmittance of the cured resins increase up to a limiting value of TMSPMA content because of the optimizing crosslink network in backbone structure. The introduction of TMSPMA may be effectively attributed to strong adhesive and high transparency of an acrylic resin series. Consequently, acrylic resins with optimal TMSPMA content can be mostly utilized as a high‐performance binder in the traffic marking paint field. [ABSTRACT FROM AUTHOR]

The glass transition temperature (Tg) of room-temperature curing epoxy adhesives is limited by the temperature used during curing. It is already known that the excess of epoxy groups can undergo a homopolymerization reaction initiated by tertiary amines at elevated temperatures, resulting in an increase in Tg. However, there is no evidence of this reaction occurring at room temperature. In the present work, the influence of formulation stoichiometry on Tg and mechanical properties was investigated. Dynamomechanical, rheological and mechanical properties of epoxy adhesives were determined by DSC, DMA, rheometer and tensile and shear strength testing. It has been probed that an excess of epoxy resin combined with a complex curing system composed of a primary amine, a polymercaptan and a tertiary amine leads to an increase in Tg up to 70 °C due to the homopolymerization reaction that takes place at room temperature. However, as the excess of epoxy resin is increased, gel time becomes slower. Regarding mechanical properties, it has been proven that an excess of epoxy resin provides a tighter and tougher material but maintains flexibility of the stoichiometric formulation, which is meant to enhance the resistance to impact-type forces, thermal shock and thermal cycling.

One-part or “just add water” alkali activated materials (AAMs) have attracted a lot of attention thanks to the use of solid alkaline activators that makes these materials more suitable to commercialization compared to conventional AAMs (two-part). This is mainly because large quantities of caustic solutions should be handled for producing conventional AAMs. So, one-part AAMs have a great potential for in-situ applications. However, heat curing (

High emissivity coatings on nickel-based superalloy, with good infrared radiating ability and good high temperature resistance, were prepared at room temperature, using preceramic polymer cured at room-temperature as coating former and CeO 2 and B 4 C as passive high emissivity fillers. The influences of high temperature and wind channel test on the microstructure and thermal performance of the high emissivity coating were investigated in detail. The high emissivity coating has good thermal stability and no cracking and flaking after heating at 1100 K and the wind tunnel test. The emissivity of the coating reached 0.85−0.92 between room temperature and 1100 K. The high emissivity coating on the nickel-based alloy can make the back temperature of the nickel-based alloy decrease from 686 to 646 ℃. [ABSTRACT FROM AUTHOR]

We report the fabrication of a corrosion‐resistant and room‐temperature curing composite latex coating with simple and environmentally friendly characteristics. Poly(vinylidene chloride) (PVDC) seed latex was first synthesized by emulsion polymerization of vinylidene chloride (VDC) monomers, subsequently the core‐shell structure of PVDC/poly(chlorotrifluoroethylene‐co‐methyl methacrylate‐co‐butyl acrylate) (PVDC/PCMB) particles were prepared via seeded emulsion copolymerization of PVDC seed particles with chlorotrifluoroethylene (CTFE), methyl methacrylate (MMA), and butyl acrylate (BA) comonomers. Furthermore, the PVDC/PCMB composite waterborne coating was smoothly fabricated. Besides, the film‐forming and anticorrosive performances could be improved by adjusting the feed ratio of acrylate comonomers in the shell layer and the core‐shell ratio, which was attributed to the synergistic effect of the low‐temperature curing PCMB nanodomains and the anticorrosive PVDC nanodomains. Moreover, the PVDC/PCMB coating still showed the outstanding corrosion resistance even after immersion in 3.5 wt% NaCl solution for 400 h. [ABSTRACT FROM AUTHOR]

SiO 2 based superhydrophobic coating has been widely studied as a promising material to extend the service life of various materials. However, the simple preparation of a robust superhydrophobic coatings with room temperature curing capability at low cost is still a challenge in this field. In this work, the fluorinated SiO 2 is made from inexpensive industrial water glass by a simple sol-gel method, and the coating is produced by a two-step brushing process and cured at room temperature. The stability of superhydrophobic coatings was verified by wear resistance, chemical stability, and high temperature resistance. Under the ideal preparation conditions obtained by hydrophobic characterizations, the contact angle can be as high as 158.9°, the slide angle is only 3.2°, and it has outstanding self-cleaning properties. The SiO 2 -EP superhydrophobic coatings notably possess exceptional wear resistance in both smooth glass and rough cement mortar surfaces. Especially on the glass, it can maintain to be superhydrophobic after being worn 50 cycles with 100 g load and 35 cycles with 200 g load on 600-mesh sandpaper. In addition, it maintains excellent superhydrophobic properties even under high temperatures of 300 °C and extreme acid and alkaline corrosive environments. This offers a broad range of application prospects for the application of superhydrophobic coatings for use on various substrates and in extreme environments. [Display omitted] • A low-cost, room-temperature curable SiO 2 -epoxy resin superhydrophobic coating. • It can be applied to various substrates, including smooth and rough surfaces. • The excellent stabilities for abrasion, high-temperature and acid-alkali corrosion. • The coating presents splendid self-cleaning properties. [ABSTRACT FROM AUTHOR]

Abstract: Cross-linked gel polymer electrolytes containing aluminum oxide nanoparticles are successfully prepared using in-situ chemical cross-linking at room temperature after injection of the gel precursor into a dye-sensitized solar cell (DSSC). This makes it possible to directly solidify the electrolyte in the cell without leakage of solvent and to maintain close interfacial contact with the porous TiO2 electrode. The quasi-solid-state DSSC assembled with gel polymer electrolyte containing 20wt.% Al2O3 particles yields an overall conversion efficiency of 5.25% under AM 1.5 illumination at 100mWcm−2. [Copyright &y& Elsevier]

[Display omitted] • Room-temperature fast-curing polybenzoxazine hybrid resins have been synthesized. • The physical state of the resin can be tuned by adjusting the thiol content. • This work provides an efficient method for room-temperature curing of benzoxazine. Room-temperature fast-curing polybenzoxazine hybrid thermosets were synthesized by crosslinking allyl-containing benzoxazine oligomer (O-ABZ) and thiol-containing siloxane oligomer (O-TS) under UV irradiation via thiol-ene click reaction. The O-ABZ was synthesized through the thermally-activated ring-opening polymerization of mono-functional benzoxazine (ABZ) obtained via Mannich reaction of the p -cresol, allylamine, and paraformaldehyde. The O-TS was synthesized by the co-hydrolysis and condensation of 3-mercaptopropylmethyldimethoxysilane with dimethyldimethoxysilane. The structures and molecular weights of O-ABZ and O-TS were characterized by FT-IR, 1H NMR, and SEC. The kinetics of thiol-ene click reaction were studied by FT-IR spectroscopy. The results showed that the curing reaction of polybenzoxazine/polysiloxane hybrid resin proceeded rapidly at room temperature under UV irradiation. The conversions of thiol and allyl groups were 56.6% and 58.3% in the first 30 s, respectively. Nearly complete curing was obtained after 3 min of UV irradiation. Meanwhile, the gel contents of the resulting resin were greater than 95%. On the other hand, the crosslinking density of the hybrids could be tuned by adjusting the thiol content of the siloxane oligomers. Their physical states transformed from rubber to plastic. [ABSTRACT FROM AUTHOR]

• The composite coatings were prepared by a low-cost and scale-up process. • The composite latex can form a film at room temperature with no baking. • Self-assembling film has dispersed phases of PVDF and continuous phases of PACL. • The waterborne coatings exhibit good adhesion and organic solvent resistance. • The coatings show super weather resistance after tolerating UV irradiation. We report a simple method for fabricating poly(vinylidene fluoride) (PVDF) /polyacrylate (PACL) composite waterborne coatings with safe, environmentally friendly and low-cost characteristics. The PVDF/PACL composite latex with functional groups was synthesized by the seeded emulsion copolymerization of PVDF and multiple acrylate monomers. By adjusting the feed ratio among different kinds of acrylate monomers, the as-prepared composite latex could easily form a film at room temperature with no baking. In addition, the self-assembly film-forming process of composite colloidal particles and the surface microstructure & performance of the latex coating were systematically explored. The water-based composite coatings presented good adhesion to the substrate and excellent weather resistance, which was attributed to the contributions of PACL and PVDF. It is worth noting that the composite coatings also had outstanding organic solvent resistance and almost retained the original gloss after tolerating repeated high-intensity UV irradiations. The composite latex fabricated by the proposed method is suitable for protective coatings of various substrates. [ABSTRACT FROM AUTHOR]