Monomeric complexes crosslinking

Tsuchida and co-workers (97) tried similar crosslinking with branched and linear poly(ethylene imin ) and W th poly(vinylimidazole) in the presence of Cu or Co ion templates, but no enhancement of selectivity towards the same metal ions was achieved. The same was true when they prepared a polymer from a monomeric complex (98). In this case the metal-1-vinylimidazole complex (from Ni, Co or Zn as the template) was copolymerized and crosslinked... 

Octahedral ruthenium(II) and osmium(II) polypyridyl complexes combine thermal and chemical stability with very interesting photophysical and electronic properties (see Chapter 2, Section 2.3.2). These considerations have prompted a range of studies that target polymers based on polypyridyl and related complexes [7]. For example, in the mid- and late 1990s, crosslinked films derived from the thermal, electro- or photopolymerization of polyfunctional monomeric complexes 7.1 and... 

Frequency dependent complex impedance measurements made over many decades of frequency provide a sensitive and convenient means for monitoring the cure process in thermosets and thermoplastics [1-4]. They are of particular importance for quality control monitoring of cure in complex resin systems because the measurement of dielectric relaxation is one of only a few instrumental techniques available for studying molecular properties in both the liquid and solid states. Furthermore, It is one of the few experimental techniques available for studying the poljfmerization process of going from a monomeric liquid of varying viscosity to a crosslinked. Insoluble, high temperature solid. 

In another approach, the fact that crystalline monomeric charge transfer complexes exhibit electrical conductivity led to preparation of polymeric charge transfer complexes. These can be obtained from a polymeric electron donor and a monomeric election acceptor or from a polymeric acceptor and a monomeric donor, the former type being the more common, These polymers are not crosslinked and some are soluble, but their conductivities are generally low,... 

Compounds 1-4, 7-13, and 16 should be appropriate as monomeric precursors for modified PA-MPs, whereas the derivatives 17, 20, and 23 must be polymerized previously. The polymerization can be carried out either dehydrogenative (compounds 20 and 23) by the use of transition metal complex catalysts or by intermolecular hydrosilylation of Si-H to the -C=C- unit (compound 17) to yield crosslinked polymeric precursors for Si-alloyed PA-MPs. 

Lignin is synthesised in plants from monomeric molecnles, whose functionality varies from two to four. Thus, both branched chain and the crosslinked structure may be formed. In plant tissue, the polymer chains of lignin are snrronnded by macromolecules of noncellulosic polysaccharides, with which they form an amorphous lignocarbohydrate matrix. The experimental methods that allow the stndy of the complex topology of macromolecules in a multicomponent solid composite are very limited. Therefore, most of the data are interpreted using theoretical methods developed from polymer chemistry. 

The nature of the fimctional groups of the macroligands is also of great importance. For instance, monomeric and polymeric amines dissociate the [Rh(CO)2RS]2 dimer complex in contrast to thiols that yield addition products. Similarly, the nature of the solvent affects chain flexibility and long-range action. For example, the Co complex with a crosslinked PS polymer has a Co L composition of 1 1 (L-monomer unit) in weakly swelling n-hexadecane, whereas a thermodynamically stable 1 2 complex forms in xylene. This observation may be a result of the fact that a PS support is glassy at 70°C in n-hexadecane and gum-like in xylene. 

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