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An In-based metal-organic framework, with 1D nanotubular open channels, In2(OH)(btc)(Hbtc)0.4(L)0.6·3H2O (1), has been synthesized via an in situ ligand reaction, in which 1,2,4-H3btc is partially transformed into the L ligand. Compound 1 exhibits exceptional thermal and chemical stability, especially in water or acidic media. The activated 1 presents highly selective sorption of carbon dioxide (CO2) over dinitrogen. Interestingly, diffuse-reflectance infrared Fourier transform spectroscopy with a carbon monoxide probe molecule demonstrates that both Lewis and Brønsted acid sites are involved in compound 1. As a result, as a heterogeneous Lewis and Brønsted acid bifunctional catalyst, 1 possesses excellent activity and recyclability for chemical fixation of CO2 coupling with epoxides into cyclic carbonates under mild conditions. In addition, the mechanism for the CO2 cycloaddition reaction has also been discussed. [ABSTRACT FROM AUTHOR]

Polyethyleneglycol borate (PEG-BAE) toughening agents were preparedfrom the esterification reaction between boric acid and PEG and characterizedby FTIR and NMR. The effect of reaction conditions such as reactiontemperatures, reaction times, and entrainer amounts on the esterificationreaction rate was studied. Incorporation of PEG-BAE into phenolic(PF) foams leads to an improvement in the flexural and compressionstrengths, and a reduced pulverization ratio compared with pure andPEG-toughened foams. The LOI results illustrate the flame-retardingeffect of PEG-BAE is better than that of pure PEG, with LOI in therange 35.5–39.0%, and all PF foams pass UL 94 V-0 rating. Conecalorimeter results indicate that the incorporation of PEG400 increasesthe peak heat-release rate (PHRR) of PF foam by 38%, whereas PEG400-BAEresults in a slightly decreased PHRR. Moreover, thermal decompositionof pure and toughened PF foams was investigated. [ABSTRACT FROM AUTHOR]