Maleic anhydride/acid copolymer with

Alkenylsuccinic anhydrides made from several linear alpha olefins are used in paper sizing, detergents, and other uses. Sulfosuccinic acid esters serve as surface active agents. Alkyd resins (qv) are used as surface coatings. Chlorendric anhydride [115-27-5] is used as a flame resistant component (see Flame retardants). Tetrahydrophthalic acid [88-98-2] and hexahydrophthalic anhydride [85-42-7] have specialty resin appHcations. Gas barrier films made by grafting maleic anhydride to polypropylene [25085-53-4] film are used in food packaging (qv). Poly(maleic anhydride) [24937-72-2] is used as a scale preventer and corrosion inhibitor (see Corrosion and corrosion control). Maleic anhydride forms copolymers with ethylene glycol methyl vinyl ethers which are partially esterified for biomedical and pharmaceutical uses (189) (see Pharmaceuticals). 

PBT has also been blended with styrene-maleic anhydride (SMA) copolymers giving materials similar to the ABS blends. Impact modification appears to be more difficult, and one must always be attentive to possible melt reaction with the anhydride, or its ring-opened acid forms, and the PBT resin. 

Because the urea-urease interaction leads to a pH increase, a polymer that increases erosion rate with increasing pH is needed. A useful polymer for this application is a partially esterified copolymer of methyl vinyl ether and maleic anhydride. This copolymer undergoes surface erosion with an erosion rate that is extraordinarily pH-dependent (J). The polymer dissolves by ionization of the carboxylic acid groups as shown below ... 

Graft reactions and functionalization reactions Graft copolymer of polystyrene and maleic anhydride graft copolymer of polyolefines and vinylsilanes graft copolymers of polyolefines and (meth)acrylic monomers, graft copolymer of EVA with acrylic acid graft copolymer of polyolefines and maleic anhydride halogenation of polyolefines or EVA... 

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. 

Various compatibilizing agents have been used to assist in the toughening of polyamides by core-shell particles Qontaining PMMA shells they include copolymers of styrene with maleic anhydride [150] and with acrylic acid [151]. Good particle dispersions and interfaces are achieved because the copolymers are miscible with the PMMA shells of the particles and react with the polyamide matrix. Blends of polyamides with ABS have been extensively studied, with copolymers of styrene and maleic anhydride again used as compatibilizers [152-156]. 

It was reported by Barb in 1953 that solvents can affect the rates of copolymerization and the composition of the copolymer in copolymerizations of styrene with maleic anhydride [145]. Later, Klumperman also observed similar solvent effects [145]. This was reviewed by Coote and coworkers [145]. A number of complexation models were proposed to describe copolymerizations of styrene and maleic anhydride and styrene with acrylonitrile. There were explanations offered for deviation from the terminal model that assumes that radical reactivity only depends on the terminal unit of the growing chain. Thus, Harwood proposed the bootstrap model based upon the study of styrene copolymerized with MAA, acrylic acid, and acrylamide [146]. It was hypothesized that solvent does not modify the inherent reactivity of the growing radical, but affects the monomer partitioning such that the concentrations of the two monomers at the reactive site (and thus their ratio) differ from that in bulk. 

To increase the starch load up to 40-60% in PO a gelatinized starch is used in the films of poly(ethylene-co-acrylic acid) (EAA) or a mixture of EAA/LDPE or LDPE/EMA (ethylene-maleic anhydride). The difficulty with this system is that the high level of filler seriously impairs the mechanical properties, especially in thin films, and the starch is subjected to moisture-absorption problems. LDPE Mn stea-rate/starch showed a decrease of MW during thermo-oxidation and an increase of MW during UV irradiation. In the mixtures, it has been estabhshed that ethylene-acrylic acid copolymer accelerates LDPE oxidative degradation while plasticized starch inhibits it [62]. 

Styrene Copolymers. Acrylonitrile, butadiene, a-methylstyrene, acryUc acid, and maleic anhydride have been copolymerized with styrene to yield commercially significant copolymers. Acrylonitrile copolymer with styrene (SAN), the largest-volume styrenic copolymer, is used in appHcations requiring increased strength and chemical resistance over PS. Most of these polymers have been prepared at the cross-over or azeotropic composition, which is ca 24 wt % acrylonitrile (see Acrylonithile polya rs Copolyp rs). 

An interesting application of this reaction was the use of macro-molecular anhydrides, namely, styrene-maleic anhydride or vinyl acetate-maleic anhydride copolymers in the presence of perchloric acid as catalyst, these copolymers acylate mesityl oxide or d rpnone to macromolecular pyrylium salts which, with aryl substituents, are fluorescent.No crystalline products could be obtained from succinic anhydride because of the solubility and ease of decarboxylation. 

Corrosion inhibiting compositions for metals subjected to highly acidic environments may be produced by reacting in a condensation reaction a styrene/ maleic anhydride copolymer with a polyamine to produce a polyimidoamine inhibitor [1568]. These inhibitors exhibit film-forming and film-persistency characteristics. Some relevant polyamines are listed in Table 6-2. 

Polymers having ionisable groups along the chain are known as polyelectrolytes. They generally exhibit properties in solution which are quite different from those with non-ionisable structures. Examples of polyelectrolytes include polyacids like poly (acrylic acid) and hydrolysed copolymers of maleic anhydride, polybases like poly (vinyl amine) and poly (4-vinyl pyridine), polyphosphates, nucleic acids, and proteins. 

The interaction of the polymer with the filler is promoted by the presence of reactive functionality in the polymer, capable of chemical reaction or hydrogen bonding with the functionality, generally hydroxyl, on the surface of the filler. Thus, carboxyl-containing polymers, e.g. ethylene-acrylic acid copolymers and maleic anhydride- and acrylic acid-grafted polyethylene and polypropylene interact readily with fillers. 

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