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Macromolecular solid state

Fourier transform infrared (FTIR) spectroscopy is the most popular method for determining the imidization process in the solid state and identifying specific substituents on the macromolecular backbone (e.g., CN, SO3H, CO, SO2).131 A method for calculating the diermal imidization extent based on FTIR data has been reported by Pride.132 Raman spectroscopy was used on the model study of PMDA-ODA condensation, and the possible formation of an inline bond by reaction of an amino group with an imide carboxyle was evidenced.133... [Pg.300]

The solid state conformations of macromolecular phosphazene chains can be successfully modeled using short chain oligomers. [Pg.383]

This chapter draws a comprehensive picture of what has been done in the field of dendrimers with polymeric cores putting emphasis first on synthetic issues and then on experiments investigating the aggregation behavior of these intruiging macromolecules both in the solid state and on surfaces. Additionally, experiments will be described which show that some of these dendrimers can be considered cylindrical molecular objects. The macromolecules treated in this chapter may be considered as either dendrimers with polymeric core or alternatively dendronized polymers (or polymers with appendent dendrons) depending on whether one sees them from the vantage point of an organic or macromolecular chemist. [Pg.175]

Shenhar R, Sanyal A, Uzun O, Nakade H, Rotello VM. Integration of recognition elements with macromolecular scaffolds effects on polymer self-assembly in the solid state. [Pg.154]

In the early stages of the development of NMR techniques (1950s-mid 1970s), the studies of polymers could be classified into two major domains broad line NMR of the solid state and the high resolution NMR of polymer liquids and solutions. In this period, crosslinked polymers were investigated by the broad line and pulsed NMR techniques, respectively. These studies in the solid state yield information primarily on macromolecular dynamics, and indirectly on the network structure. [Pg.8]

As has been shown in an ever increasing number of practical systems, particularly polymers and biological macromolecular systems, solid state NMR/I is not only useful for real solids but also very important and perhaps indispensible for neither-solid-nor-liquid samples or both-solid-and-liquid samples, which are nowadays called soft materials . Hence, there is no definite boundary between solid state and liquid state NMR/I. [Pg.105]

The structures of the element trihalides EX3 are covered in a number of textbooks on structural inorganic chemistry (4, 5), and these will not be discussed in great detail here. It is, however, worth mentioning some of the salient structural features. In most cases, a molecular trigonal pyramidal EX3 unit consistent with VSEPR theory predictions is readily apparent in the solid-state structure, although there are usually a number of fairly short intermolecular contacts or secondary bonds present. A general description of the structures as molecularly covalent but as having a tendency toward macromolecular or polymeric networks is therefore reasonable. Only in the case of the fluorides is an ionic model appropriate. [Pg.234]

The emphasis of this review clearly is on the electronic behavior of radical ions. The key ingredients of the approach taken are 1) the active physical function of the organic title systems and 2) the combination of solution and solid-state properties. Nevertheless, it should not be overlooked that some major problems of the materials science of organic radical ions can only be solved by way of synthesis. It is highly appropriate, therefore, to conclude this text by pointing out some important challenges for future work in organic and macromolecular synthesis. [Pg.90]

A HE SEARCH FOR PLASTIC, solvent-free electrolytes for use in solid-state batteries is being actively pursued in several laboratories (1-4). A number of reports have stressed the need for facile motion of the macromolecular chain in order to promote the ion conduction process in the polymer matrix, because this process occurs primarily via a free-volume mechanism (1-4). Comblike polymers with oligooxyethylene side chains constitute effective media for ion conduction of solubilized alkali salts (5-8). The low glass transition temperature (Tg) of poly(dimethylsiloxane) suggests that polysi-loxane could serve as a suitable backbone for such a comb polymer, and recent studies (9-J2) indicate this to be the case indeed. [Pg.113]

In a recent NMR study, Derenne et al.(77) obtained evidence for non hydrolyzable amide structures in refractory fractions of the algae Scenedesmus quadricauda. The solid-state NMR spectra showed a major peak around -260 ppm for amides accompanied by a peak around -195 ppm for substituted pyrroles and a shoulder at -235 ppm assigned to unsubstituted pyrroles of the insoluble residue. The authors suggest, that the amides are protected by association with long polymethylenic chains within a macromolecular network. Knicker and Hatcher offer an alternative explanation,- that protection of amide functional groups as part of proteinaceous material are affected by encapsulation within the macromolecular matrix forming sedimentaryhumic material(7.. ... [Pg.71]


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See also in sourсe #XX -- [ Pg.124 ]




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Macromolecular solids

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