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Materials made from covalently cross-linked polymer networks are ubiquitous in everyday life but are difficult to process at the end of their life cycle. Therefore, it is essential to design materials with sustainability in mind to reduce the detrimental effects of plastic waste buildup. Functionalized triazines such as 1,3,5-triazine-2,4,6-triamine (melamine), hexamethylolmelamine (HMM), and hexakis(methoxymethyl)melamine (HMMM) are key components of robust thermosets, adhesives, and coatings. We combine HMM and HMMM with an alkoxysilane to produce transparent thermosets with remarkable glass adhesion. The dynamicity of silyl ether bonds in the network makes the materials susceptible to methanolysis, enabling the recovery of HMMM and the substrate. A combination of solution- and solid-phase techniques is used to elucidate both gelation and degradation pathways. 

Abstract Due to their diverse potential in advanced electronics and energy technologies, electrically conducting metal‐organic frameworks (MOFs) are drawing significant attention. Although hexagonal 2D MOFs generally display impressive electrical conductivity because of their dual in‐plane (through bonds) and out‐of‐plane (through π‐stacked ligands) charge transport pathways, notable differences between these two orthogonal conduction routes cause anisotropic conductivity and lower bulk conductivity. To address this issue, we have developed the first redox‐complementary dual‐ligand 2D MOF Cu₃(HHTP)(HHTQ), featuring a π‐donor hexahydroxytriphenylene (HHTP) ligand and a π‐acceptor hexahydroxytricycloquinazoline (HHTQ) ligand located at alternate corners of the hexagons, which form either parallel HHTP and HHTQ stacks (AA stacking) or alternating HHTP/HHTQ stacks (AB stacking) along the c‐axis. Regardless of the stacking pattern, Cu₃(HHTP)(HHTQ) supports more effective out‐of‐plane conduction through either separate π‐donor and π‐acceptor stacks or alternating π‐donor/acceptor stacks, while promoting in‐plane conduction through the pushpull‐like heteroleptic coordination network. As a result, Cu₃(HHTP)(HHTQ) exhibits higher bulk conductivity (0.12 S/m at 295 K) than single‐ligand MOFs Cu₃(HHTP)₂(7.3 × 10⁻²S/m) and Cu₃(HHTQ)₂(5.9 × 10⁻⁴S/m). This work introduces a new design approach to improve the bulk electrical conductivity of 2D MOFs by supporting charge transport in both in‐ and out‐of‐plane direcations. 

Renewable 1,3-butadiene (1,3-BD, C4H6) was synthesized from the tandem decyclization and dehydration of biomass-derived tetrahydrofuran (THF) on weak Brønsted acid zeolite catalysts. 1,3-BD is a highly solicited monomer for the synthesis of rubbers and elastomers. Selective conversion of THF to 1,3-BD was recently measured on phosphorus-modified siliceous zeolites (P-zeosils) at both high and low space velocities, albeit with low per-site catalytic activity. In this work, we combined kinetic analyses and QM/MM calculations to evaluate the interaction of THF with the various Brønsted acid sites (BAS) of Boric (B), Phosphoric (P), and Sulfuric (S) acid modified silicalite-1 catalysts toward a dehydra-decyclization pathway to form 1,3-BD. Detailed kinetic measurements revealed that all three catalysts exhibited high selectivity to 1,3-BD ca. 64–96% in the order of S-MFI > P-MFI > B-MFI at a given temperature (360 °C). Notably, the S-MFI maintained a selectivity >90% for all evaluated process conditions. The computational results suggested that the nature of the Brønsted acid sites and the adsorption energetics (relative THF-acid site interaction energies) are distinct in each catalyst. Additionally, the protonation of THF can be improved with the addition of a water molecule acting as a proton shuttle, particularly in S-MFI. Overall, S-containing zeosils exhibited the ability to control reaction pathways and product distribution in dehydra-decyclization chemistry optimization within microporous zeolites, providing another alternative weak-acid catalytic material.