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The synthesis of 1-methoxy-2-propanol (1-MP), which is expected as a safe alternative for toxic ethylene glycol ether, is highly demanded in chemical engineering. Herein, we report a series of task-specific anion-functionalized poly(ionic liquid)s (PILs) to trigger an effective catalysis in the 1-MP production through a reaction of propylene oxide (PO) and methanol. The acquired PIL catalysts, which are induced by phenolate anions, allow extraordinary PO conversion of 90.8 % and outstanding 1-MP yield and selectivity of 86.5 % and 95.3 % under very mild conditions. It also feasibly applies to the catalysis of a wide range of alcohols and PO to synthesize propylene glycol ethers (PGEs), and shows robust and facilitate reusability. Through a DFT calculation and in-situ 2D-IR survey, we reason that these significant performances are enabled by hydrogen-bonding interaction from the imidazole on the backbone for PO activation, and by the unique nucleophilicity of anions for the generation of activated methanol. [Display omitted] • P[BVim]PhO enables production of propylene glycol monomethyl ether under mild conditions. • P[BVim]PhO shows robust and facilitate reusability. • DFT calculation and in-situ 2D-IR survey confirm the catalytic mechanism. • Our PILs activate methanol and propylene oxide by nucleophilic anions and imidazole groups. [ABSTRACT FROM AUTHOR]

In response to the First Industrial Fluid Simulation Challenge issued by the Computational Molecular Science and Engineering Forum (CoMSEF) of American Institute of Chemical Engineers (AIChE), we have performed osmotic molecular dynamics (OMD) simulations on model mixtures representing propylene + dimethyl ether and nitroethane + propylene glycol monomethyl ether (PGME) at each of two temperatures. The models are standard force-field models available in the literature for site–site interactions between heavy nuclei. Coulombic and Lennard–Jones (LJ) potentials are defined at each site and cross Lennard–Jones interactions are obtained from the Lorentz–Berthelot combining rules. OMD simulations yield the activity coefficients for each component in the mixture at the specified composition. However, because values of individual activity coefficients are less accurate for smaller mole fractions, when the composition difference across the membrane is large, we have chosen to impose thermodynamic consistency to smooth the data over the whole composition range. This is done by fitting simulated values of both activity coefficients simultaneously to the Wilson activity coefficient correlation. Pxy diagrams and data are then reported at the desired compositions for both systems at two different temperatures using the smoothed activity coefficients. [Copyright &y& Elsevier]

A series of inhalation studies with propylene glycol monomethyl ether (PGME) vapor were undertaken to characterize its subchronic toxicity in mice and chronic toxicity/oncogenicity in rats and mice. Groups of male and female Fischer 344 rats and B6C3F1 mice were exposed to 0,300, 1,000, or 3,000 ppm vapor from 1 week to 2 years. Primary treatment-related effects included: initial sedation of animals exposed to 3,000 ppm and its subsequent resolution correlating with induction of hepatic mixed function oxidase activity and S-phase DNA synthesis; elevated mortality in high-exposure male rats and mice (chronic study); elevated deposition of alpha[sub 2U]-globulin (α[sub 2U]-G) and associated nephropathy and S-phase DNA synthesis in male rat kidneys; accelerated atrophy of the adrenal gland X-zone in female mice (subchronic study only); and increased occurrence and/or severity of eosinophilic foci of altered hepatocytes in male rats. No toxicologically relevant statistically significant increases in neoplasia occurred in either species. A numerical increase in the incidence of kidney adenomas occurred in intermediate-exposure male rats; however, the association with α[sub 2U]-G nephropathy, a male rat specific effect, indicated a lack of relevance for human risk assessment. [ABSTRACT FROM AUTHOR]

• Densities of six dilute solutions of three ILs with two solvents were measured. • Compounds are [Emim][NTf 2 ], [Bmim][NTf 2 ], [Bmmim][NTf 2 ], DEC and PEGMME. • Interactions of ion-ion and ion–solvent were discussed. • Influence of methyl and methylene introduction on the properties were discussed. Different groups have important influence on the interaction between molecules. In order to understand the effect of group introduction on the molecular interaction in solution, the densities of six diluted solutions including three ionic liquids (ILs) and two organic solvents were measured. The groups include methylene and methyl. The three ILs are 1-ethyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Emim][NTf 2 ]), 1-butyl-3-methylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmim][NTf 2 ]), and 1-butyl-2,3-dimethylimidazolium bis[(trifluoromethyl)sulfonyl]imide ([Bmmim][NTf 2 ]). The organic solvents are diethyl carbonate (DEC) and propylene glycol monomethyl ether (PEGMME). The measured densities were used to calculate apparent molar volumes, V ϕ / cm 3 · m o l - 1 , from 293.15 to 328.15 K with ± 0.02 K. Then, the fitting of infinite dilution apparent molar volumes, V ϕ 0 / cm 3 · m o l - 1 , were obtained by using the calculated values of apparent molar volumes. The effects of different structures of ILs cations and organic solvents on the apparent molar volume, infinite dilution apparent molar volume, limiting apparent molar expansibility and thermal expansibility coefficient were discussed. [ABSTRACT FROM AUTHOR]