Ethylene/maleic anhydrid

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. 

Dicar bomethoxy-1,3-diphenyl Dimethyl maleate, dibenzoyl-ethylene, maleic anhydride 316... 

Examples of acid modified polyolefins are the copolymers of ethylene with acrylic acid or methacrylic acid. Variations include the partially neutralised acid copolymers with metal ions (ionomers) or terpolymers of ethylene, an acid and an acrylate such as methyl acrylate or isobutyl acrylate. Acid-containing extrudable adhesives are widely used to bond to aluminium foil. Examples of anhydride-modified polyolefins include terpolymers of ethylene, maleic anhydride and acrylates such as ethyl acrylate or butyl acrylate and the anhydride-grafted polyolefins. Some typical applications and stmctures of a variety of multilayer materials with extruded polymer tie-layer adhesives, as described in Du-Pont trade literature, are detailed in Table 16.2. 

Terpolymers of ethylene maleic anhydride and ethyl acrylate or bntyl acrylate Maleic acid and acrylate esters Low Low... 

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... 

Because the local pH at the surface of the support is lower than the bulk, or measured pH, the apparent pH optimum shifts to higher pH values with this and other negatively charged support materials. Figure 4.4 shows that chymotrypsin immobilized onto an ethylene-maleic anhydride support exhibits a pH optimum of 9.4, almost one full pH unit higher than that observed for the native enzyme. 

Figure 4.6. Enzyme bound to an ethylene-maleic anhydride carrier.

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. 

U.S. 5154847 (1992) LaPetina et al. (Helene Curtis) Ethylene-maleic anhydride resin or polyacrylic acid resin, and alkanolamide and/or wax ester Improved suspending stability improved foaming properties... 

Ethylene/maleic anhydride EMA Monsanto Polymers with amine end groups, polyamides, etc. 

Ethylene/maleic anhydride Lotrene CdF Chemie Polyamides, ionomers... 

In addition to the list, maleated polymers as coupling agents are produced by Arkema as Lotader series. They are not made by reactive extrusion. These compounds are terpolymers of ethylene, maleic anhydride and methyl, ethyl, or butyl acrylates. Acrylates make the compound rubbery and, therefore, reportedly decrease flexural modulus. 

The Fe(CO)s be removed by sublimation in vacuum. Olefins that may be used include ethylene, maleic anhydride, maleic add, fumaric add and PhCH=CHCOMe4 Olefins with strained rings may also be used to form Fe(CO)4 derivatives. The extent to which ring opening occurs depends upon the reaction... 

PE Ethylene maleic anhydride-g-PA immiscible capillary Serpe et al., 1990... 

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... 

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