Salts solid-state properties

Step-Grouch Polymerization Synthesis of a Polyurethane Foam Studies of Solutions and Gels Polymer Precipitation Gels from Alginic Acid Salts Solid State Properties... 

Ionomer. Ionomer is the generic name for polymers based on sodium or zinc salts of ethylene-methacrylic acid copolymers in which interchain ionic bonding, occurring randomly between the long-chain polymer molecules, produces solid-state properties. 

It is common practice in pharmaceutical industry to generate salt forms of a drug substance to improve solid-state properties and solubility. CE has proven its ability to analyze reliably organic acids (direct, indirect detection) and alkaline/earth alkaline metals and basic amino acids. For basic drugs, a non-toxic organic acid or inorganic acid is chosen as counterion. Acidic drug substances will usually be deprotonated by alkaline and earth alkaline... 

The first chemical transformations carried out with Cjq were reductions. After the pronounced electrophilicity of the fullerenes was recognized, electron transfer reactions with electropositive metals, organometallic compounds, strong organic donor molecules as well as electrochemical and photochemical reductions have been used to prepare fulleride salts respectively fulleride anions. Functionalized fulleride anions and salts have been mostly prepared by reactions with carbanions or by removing the proton from hydrofullerenes. Some of these systems, either functionalized or derived from pristine Cjq, exhibit extraordinary solid-state properties such as superconductivity and molecular ferromagnetism. Fullerides are promising candidates for nonlinear optical materials and may be used for enhanced photoluminescence material. 

Murata T, Enomoto Y, Saito G (2008) Exploration of charge-transfer complexes of a nucleobase crystal stracture and properties of cytosine-Et2TCNQ salt. Solid State Sci 10 1364-1368... 

Solid State Properties. Perhaps as a result of the limited intermolecular interactions of these complexes in the solid state, they exhibit few solid-state properties of interest. The dianionic 7a did successfully produce a charge transfer material by mixing it with a solution of the tetrathiafulvalene-based salt (TTF)3(BF4)2. Elemental analysis of the resulting black product gave the formula (TTF)4[7a]3 and the material exhibited a conductivity of 9 x 10 S... 

The ADtcp complexes are the most extensively studied series of Krogmann salts. In particular, the solid state properties of K2[Pt(CN)4]Br0.30 3.2H2O, KCP(Br), have been studied in great detail because of the availability of large high quality single crystals.30-32... 

Rubino, J.T. and Thomas, E.Jnence of solvent composition on the solubilities and solid-state properties of the sodium salts of some drUgfe, J. Pharm., 65, 141-145, 1990. 

Cyclic voltammetry on the cation 192 was not reversible attempted reoxidation of the reduction product of 192 produced the cation-radical of the tetraselenafulvalene 193. Apparently, the initially formed radicals dimerize rapidly with elimination of the SeEt groups at ambient temperatures. The cation-radical of 193 and various substituted derivatives have been reported,As with the sulfur analogs (see Section III,B,7,b), no comprehensive survey of the solid-state properties of these materials is attempted. In general, it is found that 193 and its derivatives, although rather more difficult to oxidize than tetrathiafulvalene counterparts, nevertheless do form electrically conducting salts and complexes. 

Unfortunately, our understanding of the physics and chemistry of salt formation is not yet at a stage where we can predict a priori the physicochemical properties of a proposed salt. A particular problem in this regard is the formation of a range of salt polymorphs and/or solvates. While qualitative/semiempi-rical guidelines have been developed, the selection process is still largely experiment based. It is to be hoped that developments in computational methods will soon lead to the more accurate prediction of bio-pharmaceutically relevant solid-state properties that will ultimately simplify the task of appropriate salt selection. 

It is obvious from the preceding discussion that salt and solid form selection are intertwined. The propensity of a compound, either neutral or a salt, to exist in different crystal forms is considered as part of the salt selection process. However, once selected for inclusion in drug product, the solid-state properties of a given compound must be evaluated in detail. The following section describes the solid-form selection process as it is carried out with a single chemical entity. 

Rubino (1989) has investigated the solid-state properties of the sodium salts of drugs (e.g., barbiturates, sulphonamides and hydantoins). When the logarithm of their aqueous... 

Some studies dealing with the solid state properties of graft copolymers with liquid-crystal side chains have appeared in the literature [353-355]. The main attention is focused on the influence of molecular parameters (nature of the backbone and the side chains, molecular weight, etc.) on the mesomorphic properties of the liquid-crystal side chain. Salt complexes of PEO grafted onto various backbones were also considered [356] and the influence of the nature of thebackbone and salts on the conductivity of the resulting materials was studied. 

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