Tag: M.W=50-100

Du, Ming-Xuan published the artcileHydrogen-Bonding Interactions in Polymer-Organic Solvent Mixtures, SDS of cas: 123-39-7, the main research area is hydrogen bonding polymer organic solvent.

Polymer solubility in organic solvents generally is predicted by the Hildebrand solubility parameter (δ) approach based on the “”like dissolves like”” principle. A conspicuous exception is that there exist many soluble pairs that the solubility parameter approach predicts to be insoluble due to the large δ difference between the pair. These cases were attributed to specific attractive interactions (e.g., hydrogen bonding) between the solute and solvent that lead to a neg. enthalpy of mixing to promote the solubility Recently, we find that the polymer solubility in ionic liquids is dominated by hydrogen-bonding interactions (Phys. Chem. Phys.2021,23, 21893-21900). More importantly, three principles based on the Kamlet-Abraham-Taft multiple-polarity scale for dealing with hydrogen-bonding interactions were proposed. Two parameters (α is the hydrogen-bond acidity parameter, and β is the basicity parameter) are required to describe hydrogen-bonding complementarity. The product of ΔαΔβ, where Δ is the difference in parameters between the polymer and solvent, is an indicator of the competition between cross-association and self-association hydrogen bonding. Therefore, an excess interaction parameter χHB, which is proportional to ΔαΔβ, can be introduced to account for the solubility promotion. In this study, these principles were used to test the solubility of polymer/organic solvent mixtures, for which the solubility parameter approach fails. These polymer/organic solvent pairs that consist of 12 polymers and 27 organic small mols. have discrepant solubility parameters (>5 MPa1/2 at least). A good correlation between the solubility data and the solubility criterion (ΔαΔβ < 0) reveals that hydrogen-bonding interactions are responsible for the solubility Therefore, the excess interaction parameter, χHB (~ΔαΔβ), provides a significant correction in the Flory-Huggins theory. This finding can also serve as a prescreening tool for the solubility of polar polymers besides the ""like dissolves like"" principle. Macromolecules (Washington, DC, United States) published new progress about Acidity. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, SDS of cas: 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Mangstl, Martin published the artcileSynthesis and characterization of methylammonium phosphates as crystalline approximants for anhydrous, low melting phosphate glasses, HPLC of Formula: 123-39-7, the main research area is methylammonium phosphate glass crystalline approximant.

Low-melting methylammonium phosphate glasses are synthesized from crystalline starting agents. To this end crystalline tris(methylammonium) cyclotriphosphate [CH3NH3]3P3O9, was synthesized by a novel and simple synthesis route from P4O10 and N-methylformamide. It, undergoes an irreversible phase transition to methylammonium catena-polyphosphate [CH3NH3]PO3. The crystal structure of the catena-polyphosphate was solved and refined from X-ray powder diffraction data by the Rietveld method using constraints obtained by solid-state 31P and 1H NMR spectroscopy. This compound crystallizes in a triclinic space group with a = 13.2236(9), b = 7.8924(6), c = 4.6553(2) Å α = 91.068(4), β = 87.840(5) and γ = 106.550(3)°. Quantum chem. calculations confirm that the obtained structure lies at an energetic min. Finally the reaction of tris(methylammonium) cyclotriphosphate and P4O10 into methylammonium phosphate glass is presented. The synthesized, water-free phosphate glass shows a very low glass transition temperature Tg of 33°C, which was verified by dynamic scanning calorimetry and NMR. The chain-like crystal structure of the high-temperature methylammoniumphosphate [CH3NH3]PO3 serves as an approximation for the short-range order of the glass.

RSC Advances published new progress about Cooling. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, HPLC of Formula: 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Qiu, Dan published the artcileSolubility, density and refractive index of formamide/N-methylformamide/N, N-dimethylformamide + Rb2SO4 + H2O ternary systems at 283.2, 298.2 and 313.2 K, Recommanded Product: N-Methylformamide, the main research area is methylformamide sulfuric acid rubidium water ternary system.

In this work, the solid-liquid equilibrium (SLE) of the ternary systems formamide (FA)/N-methylformamide (NMF)/N, N-dimethylformamide (DMF) + Rb2SO4 + H2O was measured at temperatures of 283.2, 298.2, and 313.2 K. The isothermal solubility of Rb2SO4 in mixed solvents, the d. and refractive index of the saturated solutions were determined At a given temperature, with the increase of the amide content in the mixed solvent, the saturated solubility of Rb2SO4 decreased significantly. The d. trend was consistent with the solubility However, the refractive index increased with increasing the content of amide. The solubility increased with increasing the temperature, whereas, the d. curves and refractive index curves at the three temperatures showed a point of intersection. In addition, the influence of the polarity and structure of amide on the solubility of the ternary system was also discussed. Finally, the exptl. data were fitted with empirical equations.

Journal of Chemical Thermodynamics published new progress about Density. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Recommanded Product: N-Methylformamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Pande, Vikram published the artcileDescriptors for Electrolyte-Renormalized Oxidative Stability of Solvents in Lithium-Ion Batteries, Application In Synthesis of 123-39-7, the main research area is HOMO solvent electrolyte density functional theory renormalization oxidative stability.

Electrolyte stability against oxidation is one of the important factors limiting the development of high energy d. batteries. The HOMO (HOMO) level of solvent mols. has been traditionally used for understanding trends in their oxidative stability, but this assumes a noninteracting environment. However, solvent HOMO levels are renormalized because of mols. in their solvation shells. In this work, we first demonstrate an inexpensive and accurate method to determine the HOMO level of the solvent followed by simple descriptors for renormalization of the HOMO level due to different electrolyte components. The descriptors are based on Gutmann donor and acceptor numbers of the solvent and other components. The method uses fast generalized gradient approximation-level d. functional theory calculations compared to previously used expensive, exptl. data-dependent methods. This method can be used to screen for unexplored stable solvents among the large number of known organic compounds to design novel high-voltage stable electrolytes.

Journal of Physical Chemistry Letters published new progress about Anions. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Application In Synthesis of 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Allen, Marshall J. published the artcileMechanically robust hydrophobized double network hydrogels and their fundamental salt transport properties, Product Details of C2H5NO, the main research area is salt transport property mech robust hydrophobized double network hydrogel.

Water swollen polymer networks are attractive for applications ranging from tissue regeneration to water purification For water purification, charged polymers provide excellent ion separation properties. However, many ion exchange membranes (IEMs) are brittle, necessitating the use of thick support materials that ultimately decrease throughput. To this end, novel double network hydrogels (DNHs) with variable water content are prepared and characterized in terms of mech. and ion transport properties to evaluate their potential utility as tough membrane materials. The first network contains fixed anionic charges, while the other is comprised of a copolymer with varied ratios of hydrophobic Et acrylate (EA) and hydrophilic di-Me acrylamide (DMA) repeat units. Characterization of freestanding DNH films reveals a reduction in water content from 88 to 53 wt% and a simultaneous increase in ultimate stress and strain by ∼3.5x and ∼4.5x, resp., for 95%/5% EA/DMA, relative to 100% DMA. Fundamental salt transport properties relevant to water purification, including permeability, solubility, and diffusivity, are measured and systematically compared with conventional membrane materials to inform the development of DNHs for membrane applications. The ability to simultaneously reduce water content and increase mech. integrity highlights the potential of DNHs as a synthetic platform for future membrane applications.

Journal of Polymer Science (Hoboken, NJ, United States) published new progress about Anions. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Product Details of C2H5NO.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Skarmoutsos, Ioannis published the artcileLocal intermolecular structure, hydrogen bonding and related dynamics in the liquid cis/trans N-methylformamide mixture: A density functional theory based Born-Oppenheimer molecular dynamics study, Application In Synthesis of 123-39-7, the main research area is methylformamide hydrogen bond intermol structure DFT mol dynamics.

The local intermol. structure and related dynamics in the liquid cis/trans N-methylformamide mixture at ambient temperature and d. conditions have been systematically studied by employing Born-Oppenheimer mol. dynamics simulation techniques. Particular attention has been paid to the local structure around the cis- and trans- conformers and the formation and dynamics of hydrogen bonds with their closest neighbors. The calculated atom-atom radial distribution functions are in very good agreement with available exptl. data and reveal the existence of different types of hydrogen bonding intermol. interactions. The average number of hydrogen bonds formed by the cis- conformers is higher in comparison with the one corresponding to the trans- conformers. Moreover, the lifetimes of the hydrogen bonds formed in the liquid are longer when the cis- conformers participate in the bond formation, either as donors or acceptors. These findings clearly indicate that the local structural network around the cis- conformers in the liquid is more cohesive. The latter finding is also reflected in the slower reorientational dynamics of the cis- conformers and the low- and high-frequency region of the spectral densities of the at. velocity time correlation functions. Finally, the calculated average dipole moments of the trans- and cis- conformers are significantly higher than their corresponding gas-phase values, signifying the importance of polarization effects in this particular polar liquid solvent.

Journal of Molecular Liquids published new progress about Atoms. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Application In Synthesis of 123-39-7.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Belloche, A. published the artcileRe-exploring molecular complexity with ALMA (ReMoCA): interstellar detection of urea, Name: N-Methylformamide, the main research area is urea atacama large millimeter submillimeter array ReMoCA.

Context. Urea, NH2C(O)NH2, is a mol. of great importance in organic chem. and biol. Two searches for urea in the interstellar medium have been reported in the past, but neither were conclusive. Aims. We want to take advantage of the increased sensitivity and angular resolution provided by the Atacama Large Millimeter/submillimeter Array (ALMA) to search for urea toward the hot mol. cores embedded in the high-mass-star-forming region Sgr B2(N). Methods. We used the new spectral line survey named ReMoCA (Re-exploring Mol. Complexity with ALMA) that was performed toward Sgr B2(N) with ALMA in its observing cycle 4 between 84 and 114 GHz. The spectra were analyzed under the local thermodn. equilibrium approximation We constructed a full synthetic spectrum that includes all the mols. identified so far. We used new spectroscopic predictions for urea in its vibrational ground state and first vibrationally excited state to search for this complex organic mol. in the ReMoCA data set. We employed the gas-grain chem. kinetics model MAGICKAL to interpret the astronomical observations. Results. We report the secure detection of urea toward the hot core Sgr B2(N1) at a position called N1S slightly offset from the continuum peak, which avoids obscuration by the dust. The identification of urea relies on nine clearly detected transitions. We derive a column d. of 2.7 × 1016 cm-2 for urea, two orders of magnitude lower than the column d. of formamide, and one order of magnitude below that of Me isocyanate, acetamide, and N-methylformamide. The latter mol. is reliably identified toward N1S with 60 clearly detected lines, confirming an earlier claim of its tentative interstellar detection. We report the first interstellar detections of NH2CH18O and 15NH2CHO. We also report the nondetection of urea toward the secondary hot core Sgr B2(N2) with an abundance relative to the other four species at least one order of magnitude lower than toward the main hot core. Our chem. model roughly reproduces the relative abundances of formamide, Me isocyanate, acetamide, and N-methylformamide, but it overproduces urea by at least one order of magnitude. Conclusions. Urea is clearly detected in one of the hot cores. Comparing the full chem. composition of Sgr B2(N1S) and Sgr B2(N2) may help understand why urea is at least one order of magnitude less abundant in the latter source.

Astronomy & Astrophysics published new progress about Stars. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, Name: N-Methylformamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Pendlebury, M. H. published the artcileBarriers to rotation about carbon-nitrogen bonds. I. Rotation about the carbon-nitrogen bond in mono-, di-, and trifluoroacetamide, and deuterium isotope effects upon fluorine-19 shielding, Synthetic Route of 359-38-6, the main research area is fluoroacetamide NMR; acetamide fluoro NMR; rotation carbon nitrogen fluoroacetamide; fluorine shielding fluoroacetamide.

The 19F NMR spectra of FCH2CONH2 (I) and F2CHCONH2 (II) are used to derive the activation parameters for rotation about the C-N bond; it is not possible to obtain useful results for CF3CO2NH2 (III). A total line shape anal. is used. Unusually large D isotope effects on the shielding of the 19F nucleus were observed for N-deuterated derivatives The magnitude of the isotope effect is different for I-III, and in the mono-deuterated species the isotope effect is different for cis and trans rotational isomers.

Organic Magnetic Resonance published new progress about Bond. 359-38-6 belongs to class amides-buliding-blocks, name is 2,2-Difluoroacetamide, and the molecular formula is C2H3F2NO, Synthetic Route of 359-38-6.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Claeys, E. G. published the artcileHigasi’s method for the determination of electric dipole moments, Application of 2,2-Difluoroacetamide, the main research area is .

The Higasi equation for calculating the dipole moment (CA 43, 7764a) does not require determination of n or calculation of molar refraction. Application to air- and moisture-sensitive compounds would be useful, to avoid the exposure these measurements require. Organometallic compounds of As and Sn and several halo derivs of acetamide and acetaldehyde in several solvents were used and the values for elec. moment were compared, for the classical method, and Higasi’s treatment. Agreement was within exptl. error; there was a maximum deviation of 0.17D., but an average deviation of only 0.05 D. for 14 compounds Solvent effects on measured moments are counted for both classical and Higasi methods.

Bulletin des Societes Chimiques Belges published new progress about Air. 359-38-6 belongs to class amides-buliding-blocks, name is 2,2-Difluoroacetamide, and the molecular formula is C2H3F2NO, Application of 2,2-Difluoroacetamide.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics

Brown, Trevor N. published the artcileEmpirical regressions between system parameters and solute descriptors of polyparameter linear free energy relationships (PPLFERs) for predicting solvent-air partitioning, COA of Formula: C2H5NO, the main research area is solvent air partitioning regression system parameter solute descriptor PPLFER.

Polyparameter Linear Free Energy Relationships (PPLFERs) are an empirical tool used to predict the equilibrium partitioning of solutes between two phases, referred to as a system. There are exptl. determined solute descriptors for thousands of chems., but there are only on the order of 100 systems with calibrated system parameters, the majority of which are solvents and environmental matrixes in equilibrium with air or water. The goal of this work is to create empirical regressions which use the much more numerous solute descriptors to predict the system parameters of systems which have not yet been calibrated due to a lack of partitioning data. The special case of liquid solvents in equilibrium with air is the focus of this work because this is the case in which the relationship between solute and solvent properties is most clear. First a consistent dataset of PPLFER equations was compiled using partition coefficient data from the literature to recalibrate equations for solvent-air partitioning into the Goss form (Goss, K.-U. 2005) for 89 solvents including water. All 89 solvents have also solute descriptors available in a database curated for this work which describe their behavior as solutes. The pool of descriptors drawn from to create the empirical regressions were the solute descriptors of the solvents normalized to McGowan volume (V), along with interaction parameters between the normalized descriptors. An applicability domain (AD) for the empirical regressions was defined using leverage to measure similarity to the training dataset of solvents, and solvents in the AD typically had lower RMSE for predictions. Some of the empirical regressions for the six system parameters have good predictive power (s, a, b, c) while others are only adequate (v, l). However, when these equations are combined to predict partition coefficients there is a significant cancellation of error and when predicting partition coefficients in an external validation dataset the RMSE is in the range 0.30-0.35. The empirical regressions combined with the PPLFER equations and solvent d. can also be used to predict vapor pressures as an addnl. external validation. Predictions for a dataset of vapor pressures from the literature had an RMSE of 0.26-0.75. Analyzing and comparing the results from these two external validation datasets the RMSE for predicting datasets of partition coefficients for arbitrary solutes in arbitrary systems of solvents in equilibrium with air is estimated to be 0.66 on average

Fluid Phase Equilibria published new progress about Air. 123-39-7 belongs to class amides-buliding-blocks, name is N-Methylformamide, and the molecular formula is C2H5NO, COA of Formula: C2H5NO.

Referemce:
Amide – Wikipedia,
Amide – an overview | ScienceDirect Topics