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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 [...]

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]

Cobalt 5,15-diazaporphyrin as a novel molecular catalyst immobilized onto carbon nanotubes was developed for highly efficient electrocatalytic CO2 reduction to CO with a faradaic efficiency above 99% at −0.7 V and −0.8 V versus a reversible hydrogen electrode. Compared to cobalt phthalocyanine, the decrease in electronegative nitrogen atoms at the meso position effectively increases the electron density of the central metal, making it easier to react with Lewis acid CO2. [ABSTRACT FROM AUTHOR]