Definitions of terms relating to individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers (IUPAC Recommendations 2014)

This document defines terms relating to the properties of individual macromolecules, macromolecular assemblies, polymer solutions, and amorphous bulk polymers. In the section on polymer solutions and amorphous bulk polymers, general and thermodynamic terms, dilute solutions, phase behaviour, transport properties, scattering methods, and separation methods are considered. The recommendations are a revision and expansion of the IUPAC terminology published in 1989 dealing with individual macromolecules, macromolecular assemblies, and dilute polymer solutions. New terms covering the principal theoretical and experimental developments that have occurred over the intervening years have been introduced. Polyelectrolytes are not included.△1143Ysciescopu

Caractère de microgel des cyclopolyisoprènes préparés par voie cationique

Une élude de masses moléculaires [math], de rayons de giration [math] et de viscosités intrinsèques [ƞ] a été effectuée sur deux échantillons de cyclopolyisoprènes en fonction de la température dans différents solvants. Les résultats montrent la formation des agrégats dans de mauvais solvants. Les viscosités intrinsèques et les dimensions des macromolécules restent pour tous les solvants et toutes les températures dans le même ordre de grandeur, soit quelques unités de ml/gr. De même, l’introduction de groupes polaires — Cl et — SO2Cl dans les macromolécules n’a pas pour résultat de changements importants de leur comportement en solution. La variation des valeurs de ηsp/c avec la concentration c montre une longue partie linéaire ce qui est caractéristique pour les microgels. Il en résulte que la compacité et la forme quasi-sphérique des macromolécules des cyclopolyisoprènes est due à leur réticulation intramoléculaire

Structure of bis[ethyl (trifluoroacetyl)acetato]copper(II) and its adduct with 4-(dimethylamino)pyridine: EPR and X-ray study

Bis[ethyl (trifluoroacetyl)acetato]copper(II), [Cu(etfac)(2)], has been prepared and studied by X-ray crystallography and EPR spectroscopy. The complex is centrosymmetrical and crystallizes in the P2(1)/c space group with two formula units per unit cell. After dissolving of the complex in solid matrix or in suitable solvents some changes are detected in the EPR spectra and are discussed. The EPR spectra of the complex magnetically diluted in the corresponding Pd(II) complex reveal the presence of only one paramagnetic species further denoted as B. However, EPR spectra measured in solution indicate the presence of two different paramagnetic species: (i) non-distorted parent species B, and (ii) rhombic-distorted species A, which prevail in solutions. The A:B species ratio is a function of the solvent and temperature. The [Cu(etfac)2] adduct with 4-(dimethylamino)pyridine has also been studied and found to crystallize in the C2/c space group. The adduct EPR spectrum monitored in solution shows the presence of only one paramagnetic species. (C) 2003 Elsevier B.V. All rights reserved

Polybenzimidazole-supported [Rh(cod) Cl]2 complex:effective catalyst for polymerization of substituted acetylenes.

The first heterogeneous catalyst which affords polymerization of substituted acetylenes into readily available high molecular weight polymers is reported. The catalyst (Rh/PBI) has been prepared by supporting di-mu-chloro-bis(eta(4)-cycloocta-1,5-diene)dirhodium(i), [Rh(cod)Cl](2), on commercial polybenzimidazole (PBI) porous beads by means of a simple quantitative adsorption from THF solution, and tested in polymerization of phenylacetylene, 4-fluorophenylacetylene, and 4-pentylphenylacetylene. The polymer molecules formed were found to be released from the Rh/PBI to surrounding solution during the polymerization performed in THE Formation of high molecular weight ((w) values up to 325000) polymers in prevailing cis-transoid configuration has been observed with all monomers. In a comparison with free [Rh(cod)Cl](2) used as the homogeneous catalyst, the Rh PBI can be used repeatedly, exhibits somewhat lower polymerization activity but almost no oligomerization activity, and provides polymers of higher molecular weight

Semiconducting polymer composites containing noble metal nanoparticules: preparation and optical properties

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