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Fabrication of glass with complex geocd the low resolution of particle‐based or fused glass technologies. Herein, a high‐resolution 3D printing of transparent nanoporous glass is presented, by the combination of transparent photo‐curable sol–gel printing compositions and digital light processing (DLP) technology. Multi‐component glass, including binary (Al2O3‐SiO2), ternary (ZnO‐Al2O3‐SiO2, TiO2‐Al2O3‐SiO2), and quaternary oxide (CaO‐P2O5‐Al2O3‐SiO2) nanoporous glass objects with complex shapes, high spatial resolutions, and multi‐oxide chemical compositions are fabricated, by DLP printing and subsequent sintering process. The uniform nanopores of Al2O3‐SiO2‐based nanoporous glasses with the diameter (≈6.04 nm), which is much smaller than the visible light wavelength, result in high transmittance (>95%) at the visible range. The high surface area of printed glass objectives allows post‐functionalization via the adsorption of functional guest molecules. The photoluminescence and hydrophobic modification of 3D printed glass objectives are successfully demonstrated. This work extends the scope of 3D printing to transparent nanoporous glasses with complex geometry and facile functionalization, making them available for a wide range of applications. [ABSTRACT FROM AUTHOR]

Bio‐based "thiol‐epoxides" thermosets containing dynamic cross‐linked network topologies, permanent cross‐linking and recyclability have been successfully utilized in coatings, adhesives and composites. However, these materials typically have a low glass transition temperature and limited mechanical strength. Combining excellent mechanical properties with thermal properties remains a significant challenge. In this study, we developed a recyclable itaconic acid‐based epoxy thermoset material with high glass transition temperature and tensile strength through thiol‐olefin/thiol‐epoxy click reaction and alkyl bond radical copolymerization to construct a hybrid cross‐linked network. The tensile strength reached up to (105.9 MPa) while maintaining a high Tg (93.3°C), which is the highest value reported in the literature so far. In addition, the itaconic acid‐based epoxy has excellent recyclable processing, self‐healing properties, high hardness, solvent resistance, and surface bond strength as an adhesive and coating. The results hold potential applications in achieving sustainable development in coatings and adhesives. [ABSTRACT FROM AUTHOR]

Purely organic room‐temperature phosphorescence (RTP), especially blue phosphorescence, has aroused considerable attention in organic optoelectronic applications. Herein, a purely solid supramolecular assembly with blue phosphorescence is constructed by 6‐bromoisoquinoline‐modified β‐cyclodextrin (CD‐IQ), acrylamide (AAm), and cucurbit[7]uril (CB[7]) based on in situ photopolymerization strategy, accompanied by blue RTP emission at 450 nm. The abundant hydrogen‐bonding network between the formed polyacrylamide matrix and the β‐CD effectively restricts the motion of the 6‐bromoisoquinoline chromophore and suppresses the nonradiative transition, realizing purely blue RTP emission. As compared with CD‐IQ‐polymer, supramolecular assembly between CB[7] and CD‐IQ can improve the quantum yield and lifetime from the initial 25.5% and 238.47 ms to 49.41% and 268.9 ms, respectively, which is attributed to the confinement effect of the cucurbituril hydrophobic cavity, and can be further applied in fields of anti‐counterfeiting, information encryption, and writing. [ABSTRACT FROM AUTHOR]

Endowing epoxy resin with high performance, controllable degradation as well as feasible upcycling is a huge challenge. Herein, we synthesized a bio‐based amine curing agent containing spiro diacetal unit using an environment‐friendly method, then the controllable degradable epoxy resin was obtained after the curing reaction between diamine (DVPM) and bisphenol A epoxy resin (DGEBA). Results showed that DVPM‐DGEBA resin performed high glass translation temperature of 136°C, glassy storage modulus of 3.93 GPa, and tensile strength of 85.9 MPa, owing to spiro diacetal unit and abundant methoxyl‐related hydrogen bonds confirmed by non‐isothermal fourier transform infrared spectra (FT‐IR) and dynamic mechanical analyses. More importantly, DVPM‐DGEBA resin could decompose into soluble linear oligomers in mild acidic solution. Systematically investigated by 1H nuclear magnetic resonance, gel permeation chromatography, and FT‐IR. Furthermore, the recycled oligomers could be reprocessed into thermosetting resins in the presence of diamines, and the upcycling resin performed high‐performance (glass translation temperature of 170°C, glassy storage modulus of 6.03 GPa and tensile strength of 86.4 MPa) and flame‐retardant (V‐0 rating). This work gives us some new ideas to achieve the upcycling of the thermoset resin. [ABSTRACT FROM AUTHOR]

Generally, high‐performance epoxy resins, which are derived from aromatic compounds have two major disadvantages of yellowing and brittleness, and thus it presently remains a challenge for the facile synthesis of epoxy resin with excellent ultraviolet resistance and superior strength and toughness. Herein, a novel bio‐based epoxy resin diglycidyl ester of camphoric acid (DGECA) was synthesized from the renewable camphoric acid via an efficient and scalable route. The chemical structure of DGECA was carefully characterized by Fourier transform infrared (FT‐IR), nuclear magnetic resonance (NMR), and mass spectrometry before being cured with methylhexahydrophthalic anhydride (MHHPA). Compared with the cured diglycidyl ether of bisphenol A (DGEBA)/MHHPA, the cured DGECA/MHHPA system achieved 11.5%, 16.7%, and 109.4% increment in flexural strength (126 MPa vs. 113 MPa), modulus (2.8 GPa vs. 2.4 GPa), and impact strength (6.7 kJ/m2 vs. 3.2 kJ/m2), respectively. Moreover, cured DGECA exhibited extremely lower ultraviolet absorption (0.038A) and better ultraviolet resistance than that of cured DGEBA. This work provides a new strategy to synthesize epoxy resin with excellent ultraviolet resistance and high toughness by using the unique structure of renewable feedstock. [ABSTRACT FROM AUTHOR]