Journal Article

Rapid and isothermal (at room temperature) uptake of CO2 by solutions or, in some cases, organogels comprised of a primary or secondary aliphatic amine (1) and an organic liquid leads to in situ chemical transformation to the corresponding alkylammonium alkylcarbamate (2) based gels. Chemical reversibility is demonstrated by removal of CO2 from 2-based gels upon gentle heating in the presence of nitrogen. This is a general strategy for reversible self-assembly or disassembly of molecular aggregates relying on the initiation or termination of ionic interactions.

Fifteen different low molar mass compounds are assessed as CO2 solvents based on bubble-point loci on the solvent-rich end (0.6 to 1.0 solvent wt fraction) of the CO2-solvent pressure−composition diagram at 298.15 K. Four of the five best solvents (in descending order of solvent strength on a mass fraction CO2 dissolved basis), acetone, methyl acetate, 1,4-dioxane, and 2-methoxyethyl acetate, are oxygen-rich, low molar mass species possessing one or more oxygen atoms in carbonyl, ether, and/or acetate groups that can interact favorably with CO2 via Lewis acid/Lewis base interactions.

Solubility of CO2 and N2O in Twelve Solvents, 18° to 36° C.-Since according to the Lewis-Langmuir theory these two gases have similar molecular structures, it is of interest to compare their solubilities in various liquids. In the method adopted, the air was thoroughly removed from the solvent by boiling and then the gas to be tested, having been carefully purified with the help of liquid air, was admitted and shaken up with the solvent until no further solution took place. Observations accurate to better than one per cent.

In recent years, carbon dioxide (CO2) has proven to be an environmentally friendly foaming agent for the production of polymeric foams. Until now, extrusion is used to scale-up the CO2-based foaming process. Once the production of large foamed blocks is also possible using the CO2-based foaming process, it has the potential to completely replace the currently used foam production process, thus making the world-wide foam production more sustainable.

The effects of substituents at the alpha-carbon atom on the donor properties of primary amines and amino alcohols have been studied. Such substituted amino species have important applications in industrially relevant gas separation processes. Qualitative molecular orbital arguments, along with detailed calculations at the MNDO level of theory, show that upon methyl substitution at the alpha-carbon atom the interaction of the methyl group properties of the amino species. Infrared spectroscopic data supporting the calculations are also described.

The basicity of several basic ionic liquids is studied quantitatively for the first time, and the basicity of the ionic liquids can be switched repeatedly by bubbling CO2 and N2 through the solution alternately.

The initial phase (solid or aqueous droplet) of aerosol particles prior to activation is among the critical factors in determining their cloud condensation nuclei (CCN) activity. Single-particle levitation in an electrodynamic balance (EDB) was used to measure the phase transitions and hygroscopic properties of aerosol particles of 11 organic compounds with different solubilities (10−1 to 102 g solute/100 g water). We use these data and other literature data to relate the CCN activity and hygroscopicity of organic compounds with different solubilities.

Cyanoacrylate polymer foams can be obtained by blending cyanoacrylate monomer with an appropriate solvent and a polymerization initiator. Foaming takes place in seconds at room temperature. Various monomers, solvents and initiators were tested and best performance compositions and ratios were determined. The resultant foams are lightweight and can occupy volume up to 30 times that of the original cyanoacrylate monomer. The onset time and temperature of foaming can be regulated in wide ranges. Odourless foaming compositions were obtained.

Nowadays, solvent-free, one-part cyanoacrylate adhesive is widely used in medicine and dentistry. According to a literature survey done by the authors, there are few papers concentrated on the role of nano-sized particles on the thermal behavior of cyanoacrylate glue. Thus the main goal of the current research focused on clarifying the role of nano-sized SiO2 on the thermal behavior of cyanoacrylate. Thermal behavior of all materials including cyanoacrylate and its nanocomposites was studied by using Differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) methods.

Nanofibers of poly(ethyl 2-cyanoacrylate) were directly grown via a template-less vapor phase polymerization technique directly on surface modified glass substrates. Several commercially available glass slides were investigated for polymer nanofiber deposition. In addition, glass substrates were also modified in the laboratory using silanes with different functional groups. The growth of nanofibers at different relative humidities was studied using scanning electron microscopy (SEM) and atomic force microscopy (AFM).