Salts polymers

Effect of Fiber Properties. Acid dyes are attracted to the accessible amine ends of the nylon chains located in the amorphous regions of the fiber. Acid dye affinity of nylon can be adjusted by a dding excess diamine or diacid to the polymer salt or by changing the molecular weight in polymerization. A light acid-dyeable nylon-6,6 is spun with 15—20 amine ends, expressed in terms of gram equivalents per 10 g of polymer. A medium or... 

Obtain free -poly(L-malic acid) after passage over Amberlite IR 120 (H -form) (20 ml bed volume/1 g of polymer salt). Lyophylize, dissolve powder in acetone, remove insoluble material by centrifugation, and evaporate acetone from the supernatant. 

Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterifying alkyl acrylate polymers with 4-morpholinethanol or alkanolamines and fatty alcohols or alkoxyl-ated alkylphenols and neutralizing with phosphoric acid. This polymer salt (pH of a 10% aqueous solution = 5.1) was used as an emulsifying agent for oils and waxes [70]. 

The development of monoalkyl phosphate as a low skin irritating anionic surfactant is accented in a review with 30 references on monoalkyl phosphate salts, including surface-active properties, cutaneous effects, and applications to paste and liquid-type skin cleansers, and also phosphorylation reactions from the viewpoint of industrial production [26]. Amine salts of acrylate ester polymers, which are physiologically acceptable and useful as surfactants, are prepared by transesterification of alkyl acrylate polymers with 4-morpholinethanol or the alkanolamines and fatty alcohols or alkoxylated alkylphenols, and neutralizing with carboxylic or phosphoric acid. The polymer salt was used as an emulsifying agent for oils and waxes [70]. Preparation of pharmaceutical liposomes with surfactants derived from phosphoric acid is described in [279]. Lipid bilayer vesicles comprise an anionic or zwitterionic surfactant which when dispersed in H20 at a temperature above the phase transition temperature is in a micellar phase and a second lipid which is a single-chain fatty acid, fatty acid ester, or fatty alcohol which is in an emulsion phase, and cholesterol or a derivative. 

A chemical cross-hnking of MEEP was obtained by Shriver [606] by using polyethylene glycol (PEG) dialkoxide, which also forms polymer salt complexes. The cross-linked polymers were prepared by substituting a part (1 and 10 mole%) of the methoxyethoxyethoxy ethanol by PEG in the synthesis of MEEP. Contrary to the MEEP, the amorphous polymers obtained do not flow and are stable even at 140 °C. The maximum ionic conductivity at 30 °C, obtained after complexation with liSOjCFj, are 4.1x10" S cm for MEEP/PEG 1% complexed with 6.4 wt% salt and 3x10" S cm for MEEP/PEG 10% com-plexed with 8.9 wt% salt. These values are comparable with those obtained with the parent hnear polyphosphazenes. 

In conclusion, polymer electrolytes based on phosphazene backbone and containing ether side chains are, after complexation with alkali metal salts, among the highest ionically solvent-free polymer salt complexes, with conductivities in the order of 10" -10" S cm However, these conductivities are still below the value of 10 S cm" which is considered to be the minimum for practical applications. Therefore the design of new polyphosphazenes electrolytes with a higher conductivity and also a higher dimensional stability still remains a challenge for future researchers. 

EOF reduction Organic solvents Polymers Salts Methanol, ethanol, propanol, acetonitrile Methyl cellulose, PEO, polyacrylamide, PVA... 

Unique combinations of properties continue to be discovered in inorganic and organometallic macromolecules and serve to continue a high level of interest with regard to potential applications. Thus, Allcock describes his collaborative work with Shriver (p. 250) that led to ionically conducting polyphosphazene/salt complexes with the highest ambient temperature ionic conductivities known for polymer/salt electrolytes. Electronic conductivity is found via the partial oxidation of unusual phthalocyanine siloxanes (Marks, p. 224) which contain six-coordinate rather than the usual four-coordinate Si. 

VIII. Polymer/Salt Hybrid Including Boron-Stabilized Imidoanion 190... 

VIII. POLYMER/SALT HYBRID INCLUDING BORON-STABILIZED IMIDOANION 190... 

To improve the lithium transference number, a typical approach has been the preparation of a polymer/salt hybrid,8 17 in which an ionic group is immobilized in... 

As described in previous sections (Sections VI and VII), macromolecular design of polymer/salt hybrids with a highly dissociable lithium borate unit proved to be a valuable approach for single-ion conductive polymers. To further improve the degree of lithium salt dissociation, we have designed a polymer/salt hybrid bearing the boron-stabilized imidoanion (BSI)38 (Fig. 10). 

The ionic conductivity of these polymer/salt hybrids was evaluated after the polymers were thoroughly dried under vacuum (Fig. 12a). These polymers showed... 

Figure 12 (a) Temperature dependence of ionic conductivity, (b) VFT plots for polymer/salt hybrids 10. 

Table 6 Glass Transition Temperature, Ionic Conductivity and VFT Parameters For Polymer/Salt Hybrids 10...

Two general types of polymer electrolytes have been intensively investigated, polymer-salt complexes and polyelectrolytes. A typical polymer-salt complex consists of a coordinating polymer, usually a polyether, in which a salt, e.g. LiC104, is dissolved. Fig. 5.1(a). Both anions and cations can be mobile in these types of electrolytes. By contrast, polyelectrolytes contain charged groups, either cations or anions, covalently attached to the polymer. Fig. 5.1(h), so only the counterion is mobile. 

The interaction of poly(ethylene oxide) and other polar polymers with metal salts has been known for many years (Bailey and Koleska, 1976). Fenton, Parker and Wright (1973) reported that alkali metal salts form crystalline complexes with poly(ethylene oxide) and a few years later, Wright (1975) reported that these materials exhibit significant ionic conductivity. Armand, Chabagno and Duclot (1978, 1979) recognised the potential of these materials in electro-chemical devices and this prompted them to perform more detailed electrical characterisation. These reports kindled research on the fundamentals of ion transport in polymers and detailed studies of the applications of polymer-salt complexes in a wide variety of devices. 

Many polymer-salt complexes based on PEO can be obtained as crystalline or amorphous phases depending on the composition, temperature and method of preparation. The crystalline polymer-salt complexes invariably exhibit inferior conductivity to the amorphous complexes above their glass transition temperatures, where segments of the polymer are in rapid motion. This indicates the importance of polymer segmental motion in ion transport. The high conductivity of the amorphous phase is vividly seen in the temperature-dependent conductivity of poly(ethylene oxide) complexes of metal salts. Fig. 5.3, for which a metastable amorphous phase can be prepared and compared with the corresponding crystalline material (Stainer, Hardy, Whitmore and Shriver, 1984). For systems where the amorphous and crystalline polymer-salt coexist, NMR also indicates that ion transport occurs predominantly in the amorphous phase. An early observation by Armand and later confirmed by others was that the... 

The rate of growth of polymer-salt complexes can provide fundamentally important information that is difficult to determine otherwise. The rate of crystal growth of (PEO)3 NaSCN from its undercooled liquid was measured and used to determine values for the diffusion coefficients of Na" " and SCN (Lee, Sudarsana and Crist, 1991). Also it was shown that the rate of the salt diffusion is independent of the molecular weight of the polymer for PEO molecular weights above 10. This result is fully consistent with the concept that ion motion is due to local segmental motion of the polymer. 

The structures of crystalline polymer-salt complexes provide insight into the structure of the more conducting amorphous materials. To date, large single crystals of polymer-salt complexes have not been prepared, but it has been possible to obtain structural information from single crystal X-ray diffraction applied to stretched oriented fibres in the PEO NaI and PEOiNaSCN systems (Chatani and Okamura, 1987 Chatani, Fujii, Takayanagi and Honma, 1990). One of the most detailed studies is of (PEO)3 NaI, Fig. 5.11(a). The sodium ion in this structure is coordinated to both the polymer and to the iodide ion and the polymer is coiled in the form of an extended helix. 

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