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Biomass-based polymers and their property regulation using functional materials have attracted much interest. In this work, ricinoleic acid-derived cyclic carbonate was prepared and applied to the synthesis of nonisocyanate polyurethane (NIPU) with aliphatic diamine, in which octa(aminopropyl) polyhedral oligomeric silsesquioxane (OAP-POSS) was incorporated as polyamine to partially or totally substitutes for the diamine to introduce POSS units into the polymer thus regulating the properties of the resultant material. In the curing process, Fourier transform infrared spectroscopy (FT-IR) was used to track the reaction and curing at 50[degrees]C for 12 h was found to be sufficient for the polymerization. A series of POSS modified NIPUs were obtained by altering the molar fraction of OAP-POSS in total amine components and the material with the highest thermal stability, shore hardness and water resistance was accessed with 100% substitution of OAP-POSS for diamine. KEYWORDS biomass utilization, nonisocyanate polyurethanes, POSS modification, ricinoleic acid, 1 | INTRODUCTION The excessive consumption of fossil fuels has led to massive carbon dioxide emissions, resulting in global warming and consequent detrimental environmental impacts. [1] Moreover, fossil resources are [...]

The deep eutectic solvent (DES) has emerged in recent years as a valuable medium for converting CO2 into valuable chemicals because of its easy availability, stability, and safety, and its capability to dissolve carbon dioxide. CO2 valorization in DES has evolved rapidly over the past 20 years. As well as being used as solvents for acid/base‐promoted CO2 conversion for the production of cyclic carbonates and carbamates, DESs can be used as reaction media for electrochemical CO2 reduction for formic acid and CO. Among these products, cyclic carbonates can be used as solvents and electrolytes, carbamate derivatives include the core structure of many herbicides and pesticides, and formic acid and carbon monoxide, the C1 electrochemical products, are essential raw materials in the chemical industries. An overview of the application of DESs for CO2 valorization in recent years is presented in this review, followed by a compilation and comparison of product types and reaction mechanisms within the different types of DESs, and an outlook on how CO2 valorization will be developed in the future. [ABSTRACT FROM AUTHOR]

A Cu/Co tandem catalysis protocol was developed to conduct the hydroformylation of olefins using CO2/H2 and PMHS (polymethylhydrosiloxane) as a readily available and environmentally friendly hydride source. This methodology was performed via a two‐step approach consisting of the copper‐catalyzed reduction of CO2 by hydrosilane and subsequent cobalt‐promoted hydroformylation with H2 and the in situ formed CO. The optimized triphos oxide ligand, which presumably facilitates the migratory insertion of CO gives moderate to excellent yields for both terminal and internal alkenes. This earth‐abundant metal catalysis provides a reliable and efficient way to afford useful aldehydes in industry using silicon by‐product PMHS as hydrogen source and renewable CO2 as carbonyl source. [ABSTRACT FROM AUTHOR]

Electrochemical hydrocarboxylation of enol acetates with CO2 is developed. The disclosed process provides β-acetoxycarboxylic acids in 25–66% yields, in contrast to the electrolysis of ketones, silyl enol ethers and vinyl tosylates with CO2, which leads mainly to alcohols. [ABSTRACT FROM AUTHOR]

Designing earth‐abundant metal complexes as efficient molecular photocatalysts for visible light‐driven CO2 reduction is a key challenge in artificial photosynthesis. Here, we demonstrated the first example of a mononuclear iron pyridine‐thiolate complex that functions both as a photosensitizer and catalyst for CO2 reduction. This single‐component bifunctional molecular photocatalyst efficiently reduced CO2 to formate and CO with a total turnover number (TON) of 46 and turnover frequency (TOF) of 11.5 h−1 in 4 h under visible light irradiation. Notably, the quantum yield was determined to be 8.4 % for the generation of formate and CO at 400 nm. Quenching experiments indicate that high photocatalytic activity is mainly attributed to the rapid intramolecular quenching protocol. The mechanism investigation by DFT calculation and electrochemical studies revealed that the protonation of Febpy(pyS)2 is indispensable step for photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

Efficient electrochemical CO2 reduction reaction (ECO2RR) to multi‐electron reductive products remains a great challenge. Herein, molecular engineering of copper phthalocyanines (CuPc) was explored by modifying electron‐withdrawing groups (EWGs) (cyano, sulfonate anion) and electron‐donating groups (EDGs) (methoxy, amino) to CuPc, then supporting onto carbon paper or carbon cloth by means of droplet coating, loading with carbon nanotubes and coating in polypyrrole (PPy). The results showed that the PPy‐coated CuPc effectively catalysed ECO2RR to CH4. Interestingly, experimental results and DFT calculations indicated EWGs markedly improved the selectivity of methane for the reason that the introduction of EWGs reduces electron density of catalytic active center, resulting in a positive move to initial reduction potential. Otherwise, the modification of EDGs significantly reduces the selectivity towards methane. This electronic effect and heterogenization of CuPc are facile and effective molecular engineering, benefitting the preparation of electrocatalysts for further reduction of CO2. [ABSTRACT FROM AUTHOR]

Superbase‐derived ionic liquids (SILs) are promising sorbents to tackle the carbon challenge featured by tunable interaction strength with CO2 via structural engineering, particularly the oxygenate‐derived counterparts (e. g., phenolate). However, for the widely deployed phenolate‐derived SILs, unsolved stability issues severely limited their applications leading to unfavorable and diminished CO2 chemisorption performance caused by ylide formation‐involved side reactions and the phenolate‐quinone transformation via auto‐oxidation. In this work, robust pyrazolonate‐derived SILs possessing anti‐oxidation nature were developed by introducing aza‐fused rings in the oxygenate‐derived anions, which delivered promising and tunable CO2 uptake capacity surpassing the phenolate‐based SIL via a carbonate formation pathway (O−C bond formation), as illustrated by detailed spectroscopy studies. Further theoretical calculations and experimental comparisons demonstrated the more favorable reaction enthalpy and improved anti‐oxidation properties of the pyrazolonate‐derived SILs compared with phenolate anions. The achievements being made in this work provides a promising approach to achieve efficient carbon capture by combining the benefits of strong interaction strength of oxygenate species with CO2 and the stability improvement enabled by aza‐fused rings introduction. [ABSTRACT FROM AUTHOR]