Poly esterified with maleic

Poly(vinyl alcohol) (PVA) is one of the hydrogels most often used in biomaterial applications. Because of the presence of excessive hydroxyl groups, PVA contained a significant amount of water. PVA was also claimed to have good mechanical strength. Another hydrogel, poly(2-hydroxyethyl methacrylate) (poly-HEMA), is well known for its excellent biocompatibility. xhe versatile biomedical applications of poly-HEMA are demonstrated by its uses in contact lenses, vitreous humor replacements and suture materials. To explore a new formulation and other usages of these two pol ers, we have copolymerized HEMA with PVA-MA (PVA esterified with maleic anhydride), the preparation and properties of this copolymer are discussed in this article. 

By using a combination of RAFT and ring opening polymerization (ROP), (polyethylene oxide) methyl ether)(polystyrene)(poly(L-lactide) 3-miktoarm star terpolymers have been successfully synthesized [182]. The synthetic approach involved the reaction of the cw-functionalized - OH group of the poly(ethylene oxide) methyl ether with maleic anhydride under conditions where only one hydroxyl group can be esterified (MPEO). The double bond... 

The PS half ester of maleic acid was esterified with poly(ethylene glycol) monoether or PS-fc-PEO in the presence of dicyclohexylcarbodiimide (DCC) and 1-hydroxybenzotriazole (HOBT) to give macromonomers having internal double bonds [201] (Scheme 66). 

Preparations of azide derivatives from styrene-maleic anhydride copolymers, cellulose, and gelatin by attaching aromatic azide compounds are described in the literature [175]. Most of the resultant polymers cross-link rapidly when exposed to light of 260 pm wavelength. Also, as much as 90% of the hydroxy groups of poly(vinyl alcohol) can be esterified with p-azido-benzoyl chloride. These reactions must be carried out in mixtures of chloroform and aqueous sodium hydroxide [175]. Earlier, Merrill and Unruh [175] described formation of derivatives from poly(vinyl alcohol) and attachment of aromatic azide groups. 

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). 

The hydrophobization of cellulose surface was often achieved thanks to the well-known aptitude of cellulose macromolecules to undergo esterification reactions. The main coupling agents used to esterify cellulose using nonswelling solvents, in order to limit the reaction to the fibre s surface, are summarized in Scheme 18.1, namely the classical acetic anhydride [24] (I), alkyl ketene dimer (AKD) II, alkenyl succinic anhydride (ASA) III, fatty acids (IV, with n var5fing from 6 to 22) or their chlorides, poly-(propylene-gra/f-maleic anhydride) (V), trifluoroethoxy-acetic acid (VI) and its anhydride, as well as several other perfluoro-derivatives, p5Tomellitic anhydride (VII), styrene-maleic anhydride copolymer (VIII) and methacrylic anhydride (IX). 

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