Polymers sulfonation

Aromatic compounds, 13 108-109 13 680. See also Aromatics acylation of, 12 173-181 amination of, 12 184 arylation of, 12 170-171 Cycloalkylation of, 12 169 in diesel fuel, 12 425 formylation of, 12 178 Friedel-Crafts acylation of, 12 174 Friedel-Crafts alkylation of, 12 164 nitration of, 12 182-183 oxidative coupling of, 19 654 sulfonation of, 12 181 sulfonation reagents for, 23 521-524 Aromatic-containing polymers, sulfonation of, 23 535-536... 

Post-modification treatments like storage conditions (air/water) and preconditioning may exert a pronounced influence on the zeta potential obtained for surface modified polymers. Sulfonated LDPE samples, which were subjected to an after-treatment by conditioning in an electrolyte solution, showed a shift of the zeta potential to even less negative values. This may be explained by the swelling of the polymer samples, which occur during storage in aqueous media. 

Yoshikawa and Kim (J8) studied the catalytic effect of soluble polymer sulfonic acids, such as poly(ethylensuifonic acid) J, poly (styrenesulfonic acid) 2, and partially sulfonated polystyrene 6. In the hydrolysis of ethyl acetate in aqueous acetone, the... 

TaUe 3-1. Catalytic efficiency of polymer sulfonic acids (J9)... 

Both the salinity and pol5nner concentration affect the volumetric ratios of separated phases and the fractionation of sulfonate and polymer in these phases. A proper selection of polymer concentration and salinity in a polymer-sulfonate mixture can result in equal viscosities of the separated phases (Szabo, 1979). This approach may not be practical, however, because a constant salinity or concentration cannot be maintained along the flow path because of adsorption and mixing, and so on. Therefore, we should try to select a formula that will not have an SPI problem. 

The second route to ionomers Involves modification of a preformed polymer. Sulfonation of EPDM, for example, permits the preparation of sulfonated-EPDM with a level of sulfonate groups in proportion to the amount of sulfonating agent(27). These reactions are conducted in homogeneous solutions permitting the direct neutralization of the acid functionality to the desired level. Isolation of the neutralized ionomer is effected by conventional polymer isolation techniques, such as coagulation in a nonsolvent or solvent flashing. These procedures are detailed in several patents and publications(28-31). 

Makowski HS, Lundberg RD, Singhal GH. Flexible polymer compositions comprising a normally plastic polymer sulfonated to about 0.2 to about 10 mole % sulfonate. U.S. Pat. 3,870,841, assigned to Exxon Research and Engineering Co., 1975. 

Soprophor . [Rhone-Poulenc Surf. Rhone-Poulenc Geronazzo SpA] Al-koxylated alcohols, EO/PO block polymers, sulfonates, or ethoxylates surfactant wetting and suspen g agents for degreasers, add pidding conqxls., pesticides. 

The results show clearly that, in the presence of water, the acid catalytic activity of supported sulfonic acid groups is essentially the same on polymer and silica supports, except where the level of polymer sulfonation is high, when the sulfonic acid exhibits significantly enhanced activity. The trend in molar enthalpies of neutralisation with aqueous NaOH is similar. On silica supports, and polymer supports with low sulfonic acid concentrations, these enthalpies are very similar to those of strong mineral acid solutions. In contrast, resins with high levels of sulfonation show significantly higher molar enthalpies of neutralisation. 

Table 3—1 lists polymer sulfonic acids which possess the catalytic efficiency comparable to and higher than hydrochloric acid (groups A and B, respectively). 

These studies were extended to some related systems (20). In the hydrolysis of partially acetylated polyvinyl alcohtd Why linear allqrlsulfonic acids S, the catalytic efficiency increased with increasing length of the alkyl chain. More interesting is the acid hydrolysis of the vinyl acetate unit in water-soluble copolymers by polymer sulfonic acids. Tte catalytic efficfcnty was generally greater than in other systems... 

Alkali and acid treatments have also been used to modify surface properties of polymers sulfonated polyethylene films treated first with ethylenediamine and then with a terpolymer of vinyhdene chloride, acrylonitrile, and acrylic acid exhibited better clarity and scuff resistance and reduced permeabihty. Permanently amber-colored polyethylene containers suitable for storing light-sensitive compoimds have been produced by treating fluorosulfonated polyethylene with alkali. Poly(ethylene terephthalate) dipped into trichloroacetic/chromic acid mixture has improved adhesion to polyethylene and nylons. Antifogging lenses have been prepared by exposing polystyrene films to sulfonating conditions. Acid and alkali surface treatments have also been used to produce desired properties in polymethylmethacrylates, polyacrylonitrile, styrene-butadiene resins, polyisobutylene, and natural rubber. Surface halogenation of the diene polymers natural rubber and polyisobutylene resulted in increased adhesion to polar surfaces. 

BSA BSA+ BSA- BSA- Hydrolysis blocked vinyl pPEGA of NPA polymer sulfone... 

In nanoscale catalyst particles the ratio of the different crystallographic faces are depending on the particle size thus giving an explanation for the particle size effects observed in electrolytes containing adsorbing anions. Since the perfluorinated polymer sulfonic acids are not adsorbing to the platinum sxuface, particle size effects are not so prominent in PEFC. 

Zaidi, S.M.J. 2003. Polymer sulfonation-A versatile route to prepare proton conducting membrane material for advanced technologies. Arabian J. ScL Eng. 28(2B) 183-194. 

Polysulfonate co-polymer (sulfonate-car-boxylate co-polymer) n. A family of transparent, thermoplastic polyesters, moldable at 250-300°C, and formed by reaction of a diphenol, generally bisphenol A, with an aromatic disulfonyl chloride and an aliphatic disulfonyl chloride or carboxylic acid chloride. These co-polymers have good electrical and mechanical properties, and excellent resistance to hydrolysis and aminolysis. 

Sulfonated polyester polymer Sulfonated poly(styrene)... 

When the S-PEEK-WC membranes are obtained by using concentrated sulphuric acid, a DS 40% after 3 hours of polymer sulfonation is achieved [39,40]. The S-PEEK-WC,... 

Ioti exchange membranes are primarily produced in large amounts for electrodialysis in aqueous media, e.g., for seawater desalination. They are typically made of polystyrene, cross-linked with divinylbenzene, as a base polymer. Sulfonic acid groups are introduced as fixed ions for CEM and quaternary ammonium groups for AEM. These materials may be of limited stability in combination with organic compounds due to increased swelling or even chemical attack, particularly at elevated temperatures. Simple AEMs of this type will be destroyed in alkaline media, i.e., they cannot work for longer time as OH conductor. However, many membranes made from newly developed materials are also available. Different manufacturers should be contacted to identify suitable membranes for a particular task. 

Compared to the polymer sulfone membrane, which demonstrates that the improved properties of the composite membranes induce an increase in power density, the strategy for carbon nanotube-sulfonated polyarylene sulfone composite membranes discussed here could potentially be extended to other carbon nanotube-polymer composite systems. Recent advances in the chemistry of carbon nanotube functionalization [54], and further understanding of the interaction between the carbon nanotubes and the polymer, may encourage the preparation of a variety of new composite materials. 

As an extension of our earlier work we have studied soluble conductive polymers (sulfonic acids doped polyaniline (4), poly(3-alkyl thiophenes) (5)) for the design of a new generation of microwave absorbing materials (6). These studies have own that microwave properties were very dependent on minor changes in e q)erimental procedures. Therefore it was necessary to determine how synthetic conditions effects influence structural parameters of polymers, and how these structural parameters influence electrical, optical properties and stability over time. In the case of poly(a]kylthiophene)s, solubility of polymers permits a complete structural characterization and then a better understanding of links between... 

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