Poly sulphones preparation

Not surprisingly a number of other poly(aryl ethers) have been prepared from aromatic dihalides not containing sulphone links. For example, a number have been prepared from difluorobenzophenone and, in general, it is found that such materials have TgS about 30-40°C lower than the corresponding sulphone polyether. In fact it is generally found that the higher Tg values are obtained with the sulphone polyethers. 

In these examples it was not possible to visualise any chiral structure with a microscope, but when PANI was prepared using poly(acrylic acid) as an in situ template, helical microwires were visualised [65]. In an even more general sense, helical fibres of PANI, poly(ethylenedioxythiophene) (PEDOT), and poly(pyrrole) were prepared using synthetic lipids as templates [66,67]. The synthetic lipid molecules used are shown in Fig. 6 along with some of the helical fibres of PEDOT that are formed when the sulphonate salt is used to shape the fibres during the polymerisation. The procedure involves growing the fibres by electrochemical polymerisation onto an ITO electrode with the lipid molecules in the electrolyte. 

Lee, H., Hong, H., Kim, Y-M., Choi, S., Hong, M., Lee, H., IQm, K. (2004). Preparation and evaluation of sulphonated-fluorinated poly(arylene ether)s membranes for a proton exchange membrane fule cell (PEMFC). Electrochimica Acta 49, 2315-2323. 

Poly(2-alkyl oxazoline)s having methacrylate or acrylate end groups were prepared by two methods [182]. a) Living polyoxazoline chains, prepared using methyl p-toluene sulphonate as initiator, were end-capped by reaction with metal salts or tetraalkylammonium salts of acrylic or methacrylic acid or a trialky-lammonium salt or trimethylsilyl ester of methacrylic acid (functional termination). b) The living polymers were terminated with water in the presence of Na2C03 to provide hydroxyl-terminated chains. Subsequent acylation with acry-loyl or methacryloyl chloride in the presence of triethylamine led to the formation of the macromonomers. The procedures are outlined in the following Scheme 51. 

Warren et al. [240] have explored some twenty ditferent sulphonates, mostly aromatic, in the preparation of films of polypyrrole as well as poly(3-methylthiophene), from aqueous solution and from acetonitrile solution. Only PPy-/ TS films from an aqueous medium show the splitting of diffraction peaks this is not interpreted further. Rather, the degree of order is estimated from the intensity of the diffraction peak. Benzenesulphonate ranks first in this respect. Dodecylbenzenesulphonate is also effective, and additionally shows a small-angle peak. This suggests that especially alkyl chains are effective in arranging themselves in a domain of hydrophobic character. (Dodecylbenzenesulphonic acid has been found to be an excellent surfactant for polyaniline and to facilitate its processing see Section 6.4.1.) Some of the films give spot patterns in electron diffraction. Warren et al. [240] state, however, that cell data cannot be derived from these. 

Similar to the behavior of Nafion, poly(ester sulphonic acid) ionomers selectively exclude anionic species and large particles, but cations and neutral molecules are permeable. Of the three Eastman Kodak AQ 29, AQ 38, and AQ 55 polymers, AQ 55 (see the polymer backbone in Fig. 11.12) is the most studied and most applied in biosensor preparation. Wang and coworkers described have features of this polymer as an electrode material, including strong affinity toward hydrophobic counterions, prevention of electrode fouling from proteins, stability of the polymer film on the electrode, ability to preconcentrate catalysts in the film, and lowering the overpotential of many species difficult to oxidize or reduce. Several workers also showed that this poly(ester sulphonic acid) polymer is very stable as an organic phase electrode material. ... 

Sulfonated polybenzoimidazole (sPBI) membranes have also been prepared by poly condensation of 2-sulphoterephthalic acid with 1,2,4,5-tetraaminobenzene tetrahydrochloride [193] or by grafting alkyl or aryl sulfonates on to the imidazole ring [194]. ABPBI was sulphonated by immersion in sulfuric acid followed by heat treatment at 450 °C [195]. Other methods of sulphonation have been reviewed by Asensio et al. [196], along with a detailed description of the properties of PBI blends with sulfonated and non-sulfonated polymers, and block PBI copolymers. 

Other polysulfone membranes for DMFC were prepared by sulfonation of commercial polyethersulfone with Cardo group (sPES-C) [473] (Fig. 6.9), by sulfonation of a commercial poysulfone and the use of silica as a filler [474], by "click" cycloaddition of alkyne sulphonate to polysulfone containing azide moieties and crosslinked with 1,7-octadiyne [475], and by polycondensation of 4,4 -difluorodiphenyl sulfone (DFDPS) and l,3-bis(4-fluorobenzoyl)benzene,6,7-dihydroxy-2-naphtha lene sulfonate with bisphenol [476]. Commercial poly(phtalazinone ether sulfone ketone (PPESK) [477], Udel (Solvay) polysulfone [478-480], and Lasuf Lati SPA) polysulfone [481] were sulfonated to prepare membranes for DMFC. Relative selectivity larger than 7 have been obtained with some of these membranes [477,478], as indicated in Fig. 6.37. 

A variety of poly/dihydric oils are used for the preparation of glyddyl ether-type epoxy resins. These include bisphenols, namely bisphenol-A (BPA), bisphenol-F (BPF), bisphenol-S (BPS) and bisphenol-H (BPH) and so on. Other aromatic diols and polyols such as phenolic resin, MF resins and hyperbranched polyol may also be used in the preparation of vegetable oil-based epoxy resins. Bisphenol-A (2,2-bis(4-hydroxyphenyl)propane) is one of the most widely used aromatic diols for the synthesis of epoxy resin. The resins are commonly used as lacquers for coated metal products such as food cans, bottle tops and water pipes. There are also reports on the use of bisphenol-S (BPS) (bis(4-hydroxyphenyl) sulphone), in the synthesis of epoxy resin. The advantages of resistance to deformation by heat and improvement of thermal stability were observed for such epoxy resins. The presence of sulphone group (BPS-based epoxy resin) in the epoxy resin exhibits better gel time than BPA-based epoxy. Another important diol, namely bis(4-hydroxydiphenyl)methane or bisphenol-F (BPF) is used for the synthesis of low viscosity epoxy resins. BPF generally comprises several isomers such as bis(2-hydroxylphenyl)methane (i.e. ortho-ortho isomer), bis(4-hydroxylphenyl)methane (i.e. para-para isomer) and... 

Electrolytes and solvents. The electropolymerization reaction may be sensitive to the nucleophilic nature of the solvent and electrolyte. For this reason, many of the films are prepared in aprotic solvents, such as acetonitrile, which are poor nucleophiles. Electro-oxidative polymerization in the presence of small anions simultaneously incorporates the anions which render the polymer film conductive. Upon reduction, the anions are released from the film. Cycling the film through oxidation and reduction leads to insertion and release in the respective parts of the cycle. Simultaneous incorporation or removal of the solvent and/or cations may also occur, as shown by measurements on the quartz crystal microbalance [51-52]. Polymerization in the presence of large anions such as poly(vinylsulphonate) and poly(4-styrene sulphonate) (PSS") also incorporates the anion during growth [53-56]. Subsequent cycling, however, does not release the anions which are trapped because of their... 

O. Stephan, P. Schottland, P. Y. Le Gall, C. Chevrot, C. Mariet, M. Carrier, Electrochemical behaviour of 3,4-ethylenedioxythiophene functionalized by a sulphonate group. Application to the preparation of poly(3,4-ethylenedioxythiophene) having permanent cation-exchange properties, Journal of Electroanalytical Chemistry 1998, 443, 217. 

Most types of Hot melt adhesives used in the mannfacture of laminates and in rapid Packaging industry applications are mineral oil-derived, hydrophobic and essentially non-dispersible, so they cannot be considered as renewable. However, some basic polymers have been prepared over the last decade from vegetable sources, which are renewable, and are adhesive, although these properties have limitations. These include poly(hydro-xybutyrate/hydroxyvalerate) (PHBV), poly(lactide) (which has poor thermal stability), and starch esters. Adhesives based on sulphonated polyesters with polar petroleum waxes have improved adhesion and adequate water dispersibility. In general, however, the perfect adhesive from renewable resources with satisfactory adhesion properties remains to be discovered. 

We have investigated the use of chemically prepared polyaniline and polyaniline/poly(styrene-4-sulphonate) powders rendered catalytic with Pt by various chemical deposition methods. Heating polyaniline in the presence of formaldehyde decreases its conductivity to unacceptably low values, and so effective catalysts could not be prepared by formaldehyde reduction of Pt compounds. Nanometer size (ca. 10 nm) Pt particle o>uld be depc ited by citrate reduction of H2PtCl6 without unaccepted loss of conductivity (to 10 S cm ), but the catalytic activity of tliis catalyst was not investigated since more promising results were obtained by H2 reduction of K2PtCl4, as described here. 

C. Bailly, DJ. Williams, F.E. Karasz, WJ. Macknight, The sodium salts of sulphonated poly(aryl-ether-ether-ketone) (PEEK) preparation and characterization, Polymer 28 (6) (1987) 1009-1016. 

Solanki PR, Arya SK, Singh SP, Pandey MK, Malhotra BD (2007) Application of electrochemi-cally prepared poly-N-methylpyrrole-p-toluene sulphonate films to cholesterol biosensor. Sens Actuators B Chem 123(2) 829-839... 

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