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Poly solid-state reactions with

The first poly chalcogenide complex, K4USeg, was obtained by a solid-state reaction. It has a molecular sfructure with a distorted dodecahedral anion, [U(Se2)4] , which is isosfructural with the known peroxoanions [M(02)4]" , where M = V, Nb, Ta, Cr (n = 3) or Mo, W (n = 2). Recently, two additional uranium selenides have been synthesized, MU2Se6 (M = K+, Cs+), using a reactive flux method. The oxidation state of the uranium in these compounds was found to be tetravalent. The selenium has two distinct oxidation states, Se and one similar to a polyselenide network. [Pg.26]

Recently, a novel porphyrin-based polymer, namely a poly(CO-Ru(n)-64) (with CO-Ru(n)-64 = ruthenium carbonyl spirobifluorenylporphyrin), was prepared electrochemically and used for the transfer of carbene to olefins and sulphides in a solid-state reaction. In another original study, a bimetallic porphyrin film using 65 was studied as electrode modifier with catalytic activity for molecular oxygen reduction and hydrogen peroxide reduction " . [Pg.392]

Poly(ethylene glycol) can act as both a reductant and carbon source. Compared with traditional solid-state reactions, the prepared LiFeP04/C composite has a better crystal phase, and its particle size ranges from several nanometers to several hundred nanometers. The particles are connected by a netlike carbon structure to form secondary particles. The reversible capacity is around 157 mAh/g at 0.1 C rate. No ball-milling, preparation of intermediates, presintering, or postdeposition treatment is needed. [Pg.116]

Kaeriyama et al. [10] reported on the Ni(0)-catalyzed coupling of 1,4-dibromo-2-methoxycarbonylbenzene to poly(2-methoxycarbonyl-l,4-phenylene) (4) as a soluble, processable precursor for parent PPP 1. The aromatic polyester-type PPP precursor 4 was then saponified to carboxylated PPP 5 and thermally decarboxy-latcd to 1 with CuO catalysts. However, due to the harsh reaction conditions in the final step, the reaction cannot be carried out satisfactorily in the solid state (film). [Pg.33]

The strategy of Kaeriyama represents a so-called precursor route and was developed to overcome the characteristic shortcomings (insolubility, lack of process-ability) of previous PPP syntheses. The condensation reaction is carried out with solubilized monomers, leading to a soluble polymeric intermediate. In the final reaction step this intermediate is then converted, preferentially in the solid state allowing the formation of homogeneous PPP films or layers, into PPP (or other poly(arylene)s). [Pg.33]

Much less work has been focused on the effect of polymer structure on the resist performance in these systems. This paper will describe and evaluate the chemistry and resist performance of several systems based on three matrix polymers poly(4-t-butoxycarbonyloxy-a-methylstyrene) (TBMS) (12), poly(4-t-butoxycarbonyloxystyrene-sulfone) (TBSS) (13) and TBS (14) when used in conjunction with the dinitrobenzyl tosylate (Ts), triphenylsulfonium hexafluoroarsenate (As) and triphenylsulfonium triflate (Tf) acid generators. Gas chromatography coupled with mass spectroscopy (GC/MS) has been used to study the detailed chemical reactions of these systems in both solution and the solid-state. These results are used to understand the lithographic performance of several systems. [Pg.41]

A mechanistic study by Haynes et al. demonstrated that the same basic reaction cycle operates for rhodium-catalysed methanol carbonylation in both homogeneous and supported systems [59]. The catalytically active complex [Rh(CO)2l2] was supported on an ion exchange resin based on poly(4-vinylpyridine-co-styrene-co-divinylbenzene) in which the pendant pyridyl groups had been quaternised by reaction with Mel. Heterogenisation of the Rh(I) complex was achieved by reaction of the quaternised polymer with the dimer, [Rh(CO)2l]2 (Scheme 11). Infrared spectroscopy revealed i (CO) bands for the supported [Rh(CO)2l2] anions at frequencies very similar to those observed in solution spectra. The structure of the supported complex was confirmed by EXAFS measurements, which revealed a square planar geometry comparable to that found in solution and the solid state. The first X-ray crystal structures of salts of [Rh(CO)2l2]" were also reported in this study. [Pg.202]

Amination (11) and solution carbonation (8) reactions were carried out as described previously. For solid-state carbonations, a benzene solution of poly(styryl)lithium was freeze-dried on the vacuum line followed by introduction of high-purity, gaseous carbon dioxide (Air Products, 99.99% pure). Analysis and characterization of polymeric amines (11) and carboxylic acids (8) were performed as described previously. Benzoyl derivatives of the aminated polystyrenes were prepared in toluene/pyridine (2/1. v/v) mixtures with benzoyl chloride (Aldrich, 99%). [Pg.140]

Besides in the liquid phase, some polyreactions are also performed in the solid state, for example, the polymerization of acrylamide or trioxane (see Example 3-24). The so-called post condensation, for example, in the case of polyesters (see Example 4-3), also proceeds in the solid phase. Finally, ring closure reactions on polymers with reactive heterocyclic rings in the main chain (e.g., poly-imides, see Example 4-20) are also performed in the solid state. [Pg.55]

A considerable amount of attention has also been paid to the photo-Fries rearrangement of polymer pendant groups. For example, the rearrangement of poly (phenyl acrylate) (10,11) in solution or in the solid-state, is usually incomplete and results in the formation of both the ortho and the para-hydroxyphenone rearranged products in amounts which vary with the conditions of the photolysis. A concurrent side-reaction, which we term the Fries degradation, also results in the liberation of small amounts of phenol (Scheme 2). Similar results have been obtained with poly (phenyl methacrylate) and other substituted aryl acrylates (4,9,12). [Pg.269]


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Poly , reaction with

Poly , solid

Poly reaction

Poly state

Solid state reactions

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