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Methyl vinyl ether and maleic

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 ... [Pg.173]

Figure 2. Hydrocortisone release rate at 35°C from a n-hexyl half-ester of a copolymer of methyl vinyl ether and maleic anhydride at pH 6.25 in the absence and presence of external urea. No external urea IC M external urea s10 M external urea. (Reproduced with permission from Ref. 2. Copyright 1979, American Pharmaceutical Association.)... Figure 2. Hydrocortisone release rate at 35°C from a n-hexyl half-ester of a copolymer of methyl vinyl ether and maleic anhydride at pH 6.25 in the absence and presence of external urea. No external urea IC M external urea s10 M external urea. (Reproduced with permission from Ref. 2. Copyright 1979, American Pharmaceutical Association.)...
In a very recent publication, Bergbreiter, and co-workers studied the extension of this concept using the pH value as a regulatory variable [20 b]. A phosphine-modified polyacid (a copolymer from methyl vinyl ether and maleic acid anhydride, Gantrez ) was taken as a ligand for rhodium. The rate of hydrogenation of various unsaturated substrates was reversibly modified by tuning the pH value. [Pg.335]

TM for an interpolymer of methyl vinyl ether and maleic anhydride. [Pg.595]

An interesting example is the partial esters of a methyl vinyl ether and maleic anhydride copolymer (9., 11). [Pg.376]

The first example of a surface eroding polymer was a partially esterified copolymer of methyl vinyl ether and maleic anhydride, published in 1978 [1], These polymers solubilize by ionization of carboxylic acid groups as shown in Scheme 1 and because at low pH the carboxyl groups are unionized and hence the polymer is insoluble, these materials are useful as enteric coatings to protect oral dosage forms from dissolution in the stomach [4-6]. [Pg.43]

Fig. 1. Rate of polymer erosion ( ) and rate of hydrocortisone release ( ) from thin disks of an n-butyl half ester of methyl vinyl ether and maleic anhydride at pH 7.4 and 37 °C. Drug loading 10 wt% [1], Reprinted with permission... Fig. 1. Rate of polymer erosion ( ) and rate of hydrocortisone release ( ) from thin disks of an n-butyl half ester of methyl vinyl ether and maleic anhydride at pH 7.4 and 37 °C. Drug loading 10 wt% [1], Reprinted with permission...
A.2.2 COPOLYMERS OF METHYL VINYL ETHER AND MALEIC ANHYDRIDE... [Pg.338]

To provide better control of polymer matrix erosion, a more orderly degradation and erosion process is needed. In an effort to achieve this goal, materials that erode heterogeneously have been produced. In particular, for materials that erode from the surface only, the kinetics of dissolution and the release of incorporated drugs can be precisely controlled. The first surface-eroding bio-erodible polymer formulation was produced at Alza Corp. in the 1970s it was a copolymer of methyl vinyl ether and maleic anhydride [20] ... [Pg.338]

The previous two sections reviewed characteristics of polymers that, in general, are not soluble in water and, therefore, are typically used as solid materials fibers, matrices, microspheres, or foams. Water-soluble polymers are also useful as biomaterials. Water-soluble polymers can be used in their molecular, water-soluble form as agents to modify other materials or as solid, dissolvable matrices (see the example of copolymers of methyl vinyl ether and maleic anhydride in Section A.2.2). Alternatively, water-soluble polymers may be cross-linked, by chemical or physical means, into solid materials (gels) that swell in water but do not dissolve. [Pg.346]

Synonyms 2,5-Furandione, polymerwith methoxyethene 2,5-Furandione, polymer with methoxyethylene Methyl vinyl ether/maleic anhydride copolymer Poly (maleic anhydride-methyl vinyl ether) Poly (methyl vinyl ether-alt-maleic anhydride) Poly(methyl vinyl ether/maleic anhydride) Polyvinyl methyl ether-maleic anhydride PVM/MA Definition Copolymer of methyl vinyl ether and maleic anhydride Empirical (C4H2O3 CsHsO),... [Pg.1326]

Definition Copolymer of methyl vinyl ether and maleic anhydride Empirical (C4H2O3 C3HsO)x Formula [-CHzCHOCHaCHCOOCOCH-Jn Properties Wh. powd. sol. in water, oxygenated soivs. m.w. 20,000-67,000 anionic Toxicology Toxic cancer suspect agent TSCA iisted... [Pg.3779]

Chem. Descrip. Copolymer of methyl vinyl ether and maleic anhydride Ionic Nature Anionic CAS 9011-16-9... [Pg.1547]

Uses. Union Carbide consumes its vinyl ether production in the manufacture of glutaraldehyde [111-30-8J. BASF and GAF consume most of their production as monomers (see Vinyl polymers). In addition to the homopolymers, the copolymer of methyl vinyl ether with maleic anhydride is of particular interest. [Pg.116]

Wu, C. S., Senak, L., and Malawer, E. G., Size exclusion chromatography of poly(methyl vinyl ether-co-maleic anhydride) (PMVEMA). I. The chromatographic method, J. Liq.Chromatogr., 12, 2901, 1989. [Pg.363]

Crasto, A.S., Own, S.H. and Subramanian, R.V. (1988). The influence of the interphase on composite properties Poly(cthylene-co-acrylic acid) and poly(methyl vinyl ether-co-maleic anhydride) electrode-posited on graphite fibers. Polym. Composites 9, 78-92. [Pg.321]

In fact, the copolymers of methacrylic acid with maleic anhydride (14) and the copolymers of vinyl alcohol with maleic anhydride (127) obtained respectively from optically active (l-methyl-benzyl)-methacrylate or (l-methyl-benzyl)-vinyl-ether and maleic anhydride, were optically active, but their rotatory power was rather small. [Pg.437]

Poly(methyl vinyl ether-co-maleic anhydride) and their monoalkyl ester derivatives have been shown on rabbits to be neither primary irritants nor primary sensitizers to skin and eyes The acute oral toxicities on white rats of the two copolymers are, respectively, 29 g/kg and 25 g/kg body weight. [Pg.1690]

MVE/MAN Copolymers. Various mol wt grades of poly(methyl vinyl ether-fo-maleic anhydride) (PMVEMA) are available from International Specialty Products, Inc. (formerly GAF Corp.), under the trade name of Gantrez. Table 6 illustrates the M. and MWD found for commercially available polymers. As can be seen, high molecular weights are readily achieved. [Pg.518]

Several polymers were found to fit all or most of the above criteria and were used to prepare the carrier films. Many polymers have been used for this purpose, viz., ethyl cellulose, poly(y-benzyl glutamate), poly(vinyl acetate), cellulose acetate phthalate, and the copolymer of methyl vinyl ether with maleic anhydride. In addition to the base polymers, plasticizers were often needed to impart a suitable degree of flexibility. Plasticizers, which are found to be compatible with polymeric materials include, acetylated monoglycerides, esters of phthalic acid such as dibutyl tartarate, etc. An excipient was usually incorporated into the matrix of the carrier films. The excipients used were water-soluble materials, which are capable of creating channels in the polymer matrix and facilitate diffusion of the drug. PEGs of different molecular weights were used for this purpose. [Pg.93]

Research on nasal powder drug delivery has employed polymers such as starch, dextrans, polyacrylic acid derivatives (e.g., carbopol, polycarbophil), cellulose derivatives (microcrystalline cellulose, semicrystalline cellulose, hydroxypropylmethyl cellulose, hydroxypropyl cellulose, carboxymethyl cellulose), chitosan, sodium alginate, hyaluronans, and polyanhydrides such as poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA). Many of these polymers have already been used as excipients in pharmaceutical formulations and are often referred to as first-generation bioadhesives [38-45], In nasal dry powder a single bioadhesive polymer or a... [Pg.655]

Surfactant- and Amphiphilic Acid-Assisted Synthesis PANI-NTs have been prepared by the oxidative polymerization of aniline with APS in an aqueous solution in the presence of SDS [82,328], SDBS [329], a mixture of ionic surfactants (CTAB and SDBS) [204], polymeric acids [330] e.g. poly(methyl vinyl ether-alt-maleic acid) [331-334] (Figure 2.16), poly(3-thiopheneacetic acid) [70], PSSA and PAA (Figure 2.16) [333],... [Pg.44]

Figure 2.16 SEM and TEM images of PANI-NTs obtained from solutions that contained different polymeric acids (A) PSSA, (B) PAA and (C) poly (methyl vinyl ether-alt-maleic acid). The synthesis conditions were 0.1 M aniline, 2 wt% of the polyacid, which were reacted for 16 h at 3°C. (Reprinted with permission from Current Applied Physics, Polyaniline nanotubes doped with polymeric acids by L. Zhang, H. Peng, J. Sui et al., 8, 3, 312-315. Copyright (2008) Elsevier Ltd)... Figure 2.16 SEM and TEM images of PANI-NTs obtained from solutions that contained different polymeric acids (A) PSSA, (B) PAA and (C) poly (methyl vinyl ether-alt-maleic acid). The synthesis conditions were 0.1 M aniline, 2 wt% of the polyacid, which were reacted for 16 h at 3°C. (Reprinted with permission from Current Applied Physics, Polyaniline nanotubes doped with polymeric acids by L. Zhang, H. Peng, J. Sui et al., 8, 3, 312-315. Copyright (2008) Elsevier Ltd)...
Mixtures of hydrocoUoidal gelling agents in an aqueous medium have also been employed as water-soluble or water-dispersible additives to provide gels having solids-suspending properties. Such mixtures include a mixture of hydroxypropyl-cellulose and poly(l-alkene-maleic anhydride) as poly(isobutylene-co-maleic anhydride), and a blend of hydroxypropylcellulose and poly(alkyl vinyl ether-co-maleic anhydride) as poly(methyl vinyl ether-co-maleic anhydride) [91]. [Pg.271]

Journal of Applied Polymer Science 91, No.3, 5th Feb.2004, p. 1576-89 INFLUENCE OF PLASTICISER TYPE AND STORAGE CONDITIONS ON PROPERTIES OF POLY(METHYL VINYL ETHER-CO-MALEIC ANHYDRIDE) BIOADHESIVE FILMS Hou T H Costen R C... [Pg.52]

M. Karahan, S. Tuglu, and Z. Mustafaeva, Synthesis of microwave-assisted poly(methyl vinyl ether-co-maleic anhydride)-bovine sermn cdbumin bioconjugates, Artif. Cells Blood Substit. Biotechnol., 40 (6), 363-368,2012. [Pg.300]


See other pages where Methyl vinyl ether and maleic is mentioned: [Pg.44]    [Pg.1417]    [Pg.44]    [Pg.1417]    [Pg.325]    [Pg.363]    [Pg.27]    [Pg.666]    [Pg.68]    [Pg.558]    [Pg.123]    [Pg.98]    [Pg.300]    [Pg.228]   


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