Ethylene-maleic anhydride copolymer

Superabsorbent polymers are now commonly made from the polymerization of acrylic acid blended with sodium hydroxide in the presence of an initiator to form a polyacrylic acid, sodium salt (sometimes referred to as cross-linked sodium polyacrylate). Some of the polymers include polyacrylamide copolymer, ethylene maleic anhydride copolymer, cross-linked carboxy-methyl-cellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch grafted copolymer of polyacrylonitrile to name a few. The latter is one of the oldest SAP forms created. 

Anhydride Groups. Anhydride groups present on commercially available ethylene-maleic anhydride copolymers are readily reactive with the nucleophile-containing amino acid residues of proteins.11 These groups react directly with lysine residues, for example, to form amide bonds (4.16) ... 

Figure 4.4. Relative activity versus pH for (b) native chymotrypsin (optimum pH 8.6) and for chymotrypsin bound to (a) polyomithine (optimum pH 7.0), (c) ethylene-maleic anhydride copolymer (optimum pH 9.4). [Reprinted, with permission, from L. Goldstein and E. Katchalski, Fresnius s Z Anal. Chem. 243, 1968, 375-396. Use of Water-Insoluble Enzyme Derivatives in Biochemical Analysis and Separation . 1968 by Springer.]...

The optimum pH for an enzymatic reaction may shift by as much as 3 pH units upon immobilization.24 This shift is a result of both the charge of the support material and the chemical modification of the enzyme. Figure 4.4 illustrates the dramatic shifts that occur in the pH optimum of chymotrypsin, a proteolytic enzyme, following covalent immobilizations onto a polyornithine (positive) carrier and an ethylene-maleic anhydride copolymer (negative). 

When chymotrypsin is immobilized onto the ethylene-maleic anhydride copolymer, one acidic group is created on the surface for each enzyme molecule immobilized, as shown in Figure 4.6. This and other negatively charged supports attract H+ from the bulk of the solution to the surface of the carrier, so that the local pH at the surface is lower... 

Suggest how the covalent immobilization of urease onto particles of an ethylene-maleic anhydride copolymer might be expected to change (a) its apparent pH optimum, and (b) its apparent Km for urea. 

EMA resins [Solutia], TM for ethylene-maleic anhydride copolymers. Water-soluble resins that serve as dispersing agents in cold-water detergents, thickeners, binders, stabilizers, and emulsifiers. 

Chem. Descrip. Ethylene-maleic anhydride copolymer CAS 9006-26-2... 

Synonyms EMA Ethylene/maleic anhydride copolymer 2,5-Furandione, polper with ethene Maleic anhydride/polyethylene copolymer Definition Polymer of ethylene and maleic anhydride monomers Formula [CH CHJ.ICHCOOHCHCOOH],... 

Ethylene/maleic anhydride copolymer. See Ethylene/MA copolymer... 

Thermoplastic starch can also be blended with other polymers such as polyolefins [115]. In this sort of blend, a compatibilizer such as ethylene-maleic anhydride copolymer can be used in order to make hydroxyl starch groups and anhydride copolymer groups to react and obtain ester bonds. This sort of esterification helps to compatibilize the starch (hydrophilic) with polyolefins (lipophilic). 

Ethylene/maleic anhydride copolymer. See Ethylene/MA copolymer Ethylene mercaptan. See Ethylene dimercaptan Ethylene mercaptoacetate. See Glycol dimercaptoacetate Ethylene/methacrylic acid copolymer CAS 25053-53-6... 

Blends of poly (vinyl alcohol) with polycaprolactone [60] and ethylene-maleic anhydride copolymers [61] are also used in biodegradable packaging, though the latter blend is unlikely to be biodegradable. 

L. Goldstein, Immobilized enzymes the coupling of biologically active proteins to ethylene-maleic anhydride copolymers of different anhydride content. Analyt. Biochem., 50 (1), 40-46, 1972. 

One patented method of separating the undesirable high molecular weight fraction involves the formation of complexes of the polymer with poly (acrylic acid) or with an ethylene-maleic anhydride copolymer. The procedure is outlined here for reference only. 

Poly(acrylamide) copolymer Ethylene maleic anhydride copolymer Crosslinked carboxy-methylcellulose Poly(vinyl alcohol) copolymers Crosslinked poly(ethylene oxide)... 

Enzymes were first reacted in Germany with insoluble synthetic particles such as derivatives of polystyrene or of methacrylic acid (Manecke) [23]. They were combined in the famous group of Ephraim Katchalski, in Israel, with synthetic polypeptides [24], then linked to ethylen-maleic anhydride copolymers [28] or included in collodion membranes [20] similar to those used earlier by Sollner [2] to prepare charged membranes. 

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