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A nanocomposite able to function as a hydrogenation catalyst under strongly acidic conditions without the presence of noble metals is synthesized and thoroughly studied. This specially designed catalyst possesses a unique structure composed of carbon nitride (CN) with underlying nickel, in which the nickel endows the CN with new active sites for hydrogen adsorption and activation while it itself is physically isolated from the reactive environment and protected from poisoning or loss. The CN is inert for hydrogenation without the help of nickel. The catalyst shows good performance for hydrogenation of nitro compounds under strong acidic conditions, including the one-step hydrogenation of nitrobenzene in 1.5 M H 2 SO 4 to produce p-amoniophenol, for which the acid in the reaction system has restricted the catalyst only to noble metals in previous studies. Further characterization has demonstrated that the nickel in the catalyst is in an electron-deficient state because some of its electron has been donated to CN (HRTEM, PES); thus, the hydrogen can be directly adsorbed and activated by the CN (HD exchange, in situ IR and NMR). With this structure, the active nickel is protected by inert CN from the corrosion of acid, and the inert CN is activated by the nickel for catalytic hydrogenation. The assembly of them gives a new catalyst that is effective and stable for hydrogenation even under a strongly acidic environment.

In this study, novel biobased pressure-sensitive adhesives (PSAs) derived from epoxidized soybean oils and carboxylic acid-terminated polyesters were developed with flame retardance, thermal stability, and peel strength comparable to those of current PSAs. The dynamic mechanical analysis indicated that the PSAs exhibited a dynamic mechanical response consistent with related high-performance PSAs. The thermal properties of the PSAs were investigated by thermogravimetric analysis, and the results suggested that the onset decomposition temperatures in both nitrogen and air atmospheres were improved by incorporating both 9,10-dihydro-10-[2,3-di­(hydroxycarbonyl)­propyl]-10-phosphaphenanthrene-10-oxide (DDP) and 2-(6-oxido-6H-dibenz<1,2>oxaphosphorin-6-yl)-1,4-hydroxyethoxyphenylene (DOPO-HQ-HE) as the flame-retardant monomer. Microscale combustion calorimetry, the limiting oxygen index test, UL-94, and the test method for flame resistance of PSA tapes were used to evaluate the flame retardance of the PSAs. With an increase in the content of the flame-retardant monomers, the flame retardance of two phosphorus-containing PSAs improved. The PSAs were based on renewable materials without any volatile organic compound, thus being environmentally friendly together with having the expected thermal stability and flame retardance. If we take advantage of these features, the PSAs can provide more opportunities for versatile applications.

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