Resins polymeric cation-exchange

Cation exchange resins, polymeric perfluorinated resinsulfonic acids... 

Polymeric cation-exchange resins are also used in the separation of fmctose from glucose. The UOP Sarex process has employed both 2eohtic and polymeric resin adsorbents for the production of high fmctose com symp (HFCS). The operating characteristics of these two adsorbents are substantially different and have been compared in terms of fundamental characteristics such as capacity, selectivity, and adsorption kinetics (51). 

Methyl Isopropenyl Ketone. Methyl isopropenyl ketone [814-78-8] (3-methyl-3-buten-2-one) is a colorless, lachrymatory Hquid, which like methyl vinyl ketone readily polymerizes on exposure to heat and light. Methyl isopropenyl ketone is produced by the condensation of methyl ethyl ketone and formaldehyde over an acid cation-exchange resin at 130°C and 1.5 MPa (218 psi) (274). Other methods are possible (275—280). Methyl isopropenyl ketone can be used as a comonomer which promotes photochemical degradation in polymeric materials. It is commercially available in North America (281). 

Strong-acid catalysts, in phenolic resin polymerization, 73 760-761 Strong acid cation-exchange resins, 74 381-382... 

The bile acid-binding agents are large polymeric cationic exchange resins that are insoluble in water. They bind bile acids in the intestinal lumen and prevent their reabsorption. The resin itself is not absorbed. 

Thiophenes are known to polymerize on treatment with acidic materials this is probably due to successive protonation and electrophilic substitution. It has been reported (79BCJ1126) that 2-chlorothiophene (80) on treatment with Amberlyst 15 (cation exchange resin) and 100% orthophosphoric acid gives (82) and (84) as major products and (83) as a minor one. The suggested mechanism involves initial protonation to form (81), which subsequently acts as an electrophile (Scheme 13). Related dimerizations have been reported on treatment of benzo[6]thiophene with A1C13 <80JCS(P1)677, 81JCR(S)307>. 

Exercise 25-10 A cation-exchange resin can be prepared by radical-addition polymerization of phenylethene (styrene, Section 10-8) in the presence of about... 

The separation of peptides by means of this technique makes use of two types of ion exchangers cation exchangers to separate neutral and basic peptides (76,76a,b) and anion exchangers to separate neutral and acid peptides (77). Some workers have separated peptides in polymeric cation-exchange resins (polystyrene divinylbenzene) (78), and automatic peptide analyzers similar to those used in analyses of amino acids have even been designed, with postcolumn detection using... 

Jahn, A., and R H. Neilsen. 1993. Extraction of extracellular polymeric substances (EPS) from biofilms using a cation exchange resin. Water Science and Technology 32 157-164. 

Ion-exchange polymeric resins are the most important types of exchangers currently in use [113-123], The first, totally organic ion-exchange resin was synthesized in 1935 by Adams and Holmer, when they produced a phenol-formaldehyde cation-exchange resin and an amine-formaldehyde anion-exchange resin, both obtained with the help of condensation polymerization reactions [113], In 1944, D Alelio synthesized styrene-based polymeric resins, which could be modified to obtain both cationic- and anionic-exchange resins. The majority of the resins commercially applied currently are of this type, for example, Amberlite IR-20, Lewatit S-100, Permutit Q, Duolite, C-20, Dowex-50, and Nalcite HCR. 

Degradation of beet arabinan and yeast mannan afforded osazones which, on hydrolysis in ethanolic solution with a cationic exchange resin in the acid state, yielded arabinose and a mannobiose, respectively, together with glycerosazone. These results, and also the nitrogen content of the polymeric materials recovered after Barry degradations, show that... 

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