Alkyl vinyl ether-maleic anhydride copolymer

C.W. Woodruff, G.E. Peck, and G.S. Banker, Dissolution of alkyl vinyl ether-maleic anhydride copolymers and esther derivatives,/. Pharm. Sci., 61 (12), 1916-1921,1972. 

A.4. Alkyl Vinyl Ether-Maleic Anhydride Copolymer Patents A. 5. Vinyl Acetate-Maleic Anhydride Copolymer Patents A.6. Patents on Maleic Anhydride Copolymers with Miscellaneous Monomers... 

Table A.4. Alkyl Vinyl Ether-Maleic Anhydride Copolymer Patents... 

Polymeric anhydrides can be prepared by the above techniques and are beginning to find various commercial uses. These are the styrene-maleic anhydride copolymers and the alkyl vinyl ether-maleic anhydride copolymers. The use of maleic acid or itaconic acid is widely used in the polymer field to give copolymers with anhydride functionality. 

Besides vinyl acetate monomer, three other components are neeessary to earry out an emulsion polymerization water, an emulsifier and/or a proteetive eolloid, and a water-soluble initiator. Most commonly, anionic long-chain alkyl sulfonates are used as surfactants in amounts up to 6%. Studies have shown that the rate of polymerization is dependent on the amoimt of emulsifier present, with the rates inereasing as the amoimt of emulsifier is increased up to a certain point and then falling olF as free-radieal ehain transfer to the surfaetant beeomes a serious competing side reaetion [240]. In general, surfactants are used in eombination with a protective colloid. Especially useful as protective colloids are poly(vinyl alcohol), hydroxyethyl cellulose, alkyl vinyl ether-maleic anhydride and styrene-allyl alcohol copolymers, and gum arable. Water-soluble initiators, particularly potassium persulfate, alkali peroxydisulfates, hydrogen peroxide, and various redox systems, are most commonly used. 

The interactions of a-olefins or styrene with sulfur dioxide (16) or a-olefins (24, 58, 78), frans-stilbene (64), styrene (1,63), p-dioxene (52), 2,2-dimethyl-l,3-dioxole (17), or alkyl vinyl ethers (1, 63) with maleic anhydride yield charge transfer complexes which are stable and generally readily detectable either visually or by their ultraviolet absorption spectra. However, under the influence of a sufficiently energetic attack in the form of heat or free radicals, the diradical complexes open, and alternating copolymers are formed. 

In studies on hydrophobic interactions and conformational transitions of selected hydrolyzed maleic anhydride-alkyl vinyl ether copolymers (I, 2), we found that under certain conditions neutralization by base caused phase separation in aqueous solutions of the hexyl and octyl copolymers. Both the hexyl and octyl copolymers are insoluble at low pH and require partial neutralization by a base for complete dissolution. Under certain conditions, these copolymers will again precipitate as their degree of neutralization is raised with more base. Insolubility at low pH has been reported for other polyacids (3, 4). However, the phase separation at high pH contradicts the wealth of data indicating that neutralization increases the water affinity of polyacids. 

Attempts have been made over time to improve the physical properties of novolacs. The use of phenol formaldehyde resins prepared in alkaline medium in photoresist compositions is mentioned in a Kalle Co. AG patent. The use of polyvinyl ethers in combination with novolacs to impart stickiness and plasticization action to the latter was patented by Christensen. Steinhoff, Isaacson, and Roelants of the Shipley Company mention the use of vinyl ethers in a patent on roller coating. Lower alkyl polyvinyl ethers, such as methyl, ethyl, butyl, and isobutyl, are added to novolac resins to improve coating flexibility and adhesion to metal surfaces as well as to improve resistance to mildly alkaline solutions. The use of styrene, methyl styrene, and styrene-maleic anhydride copolymers in combination with novolac was mentioned in several patents of both Shipley and Kalle Co. AG. When novolac is copolymerized with maleic anhydride, a resin that is readily soluble in alkaline solutions is obtained. ... 

Alternating copolymers ( interpolymers ) of maleic anhydride and alkyl vinyl ethers are prepared by free radical polymerization in solvent, non-solvent or bulk media Products prepared from ethyl-, butyl-, hexyl-, and octyl-, and decyl- vinyl ethers are described in Table I. The decyl-copolymer was prepared by Dr A. W. Schultz. A methyl-copolymer ( Gantrez AN General Aniline and Film Corp.), not described in Table I, was included in some studies. Molecular weight estimates were... 

Maleic copolymers, especially those with alkyl vinyl ethers, were used in drug formulations where only physical interactions occurred between the polymer matrix and the therapeutic agent. The polymers used in the formulations should be biocompatible, nontoxic, and should not induce allergic or pyrogenic reactions. Poly(maleic anhydride-co-methyl vinyl ether) (MA-MVE) is such a polymer, being approved by the FDA. Commercialized as Gantrez AN, MA-MVE copolymer is used as pharmaceutical excipient due to its bio/mucoadhesion and excellent film-forming properties [137]. 

Free-radical copolymerization of alkyl vinyl ethers has been carried out with the following typical monomers acrylic acid (bulk and emulsion) [39,40], acrylonitrile (emulsion) [26,27], acrylic esters (emulsion) [41], methyl methacrylate (bulk) [42], maleic anhydride (solution) [43], vinyl acetate (bulk and emulsion) [27,44,45], and vinyl chloride (emulsion) [26, 37,46]. The properties of these and other copolymers are described in a technical bulletin by General Aniline Film Corporation [38]. 

Strauss UP, Vesnaver G (1975) Optical probes in polyelectrolyte studies. 2. Fluorescence-spectra of dansylated copolymers of maleic-anhydride and alkyl vinyl ethers. J Phys Chem 79 (22) 2426-2429. doi 10.1021/j 100589a017... 

The data presented here constitute part of the results attained in the development of a research project funded by the European Community (EC) and performed in cooperation with three independent European companies [6]. Hybrid polymeric materials based on intimate blends of human serum albumin (HSA), alkyl hemiesters of alternating copolymers of maleic anhydride (MAn), and vinyl ethers of monomethoxyoligoethylene glycols (PEGVE) were selected as biocompatible matrices for the formulation of the nanoparticles. 

The preparation and characterization of alternating copolymers of Maleic anhydride (MAn) and poly (ethylene glycol-vinyl ether) as well as their chemical conversions to provide various alkyl hemiesters (Scheme 1) have been described elsewhere [7]. The matrices are quoted as PAMm z, where m represent the number of oxyethylene units in R and n the number of carbon atoms in R. Human serum albumin (HSA) was provided by Isti-tuto Sierovaccinogeno Italiano SpA, Italy. 

According to most sources, the homopolymer of the vinyl alkyl ethers react to ionizing radiation predominantly by cross-linking 18). It is safe to conclude that maleic anhydride has contributed a predominance of chain scissioning to the copolymer and that, if cross-linking does take place, it is in very small proportion. 

The processing properties of poly(vinyl chloride) has been improved by copolymerizing vinyl chloride with a small amount of vinyl alkyl ether. Copolymers of vinyl alkyl ethers and maleic anhydride arc used as water soluble thickeners, paper additives, textile assistants and in cleaning formulations. 

Hydrophobic regions can be one or two small, well-defined blocks of pendant hydrophobic moieties in an otherwise water-soluble polymer (2-4). An example is a water-soluble sulfonated BAB triblock copolymer where B is hydrophobic f-butylstyrene and A is vinyltoluene (2). However, hydro-phobic regions can also be less well-defined as well as more numerous in a polymer molecule than is the case for a triblock copolymer (5-22). For example, pendant alkyl esters appear to have been randomly incorporated in styrene-maleic anhydride (5) and vinyl benzyl ether-styrene-maleic anhydride (6-ii) copolymers. Also, alkyl polyoxyethylene acrylate monomers can be copolymerized with acrylamide to yield copolymers with pendant hydrophobic chains (12-15). More recently it was found (16-22) that small amounts of water-insoluble monomers that are solubilized by surfactants into aqueous solutions of a hydrophilic monomer produce copolymers with pendant hydrophobic chains, but the size, number, and nature of the hydro-phobic regions has not been determined. 

The 1-1 copolymer of maleic anhydride and methylvinyl ether were commercial products and were used without fractionnation. The copolymers of maleic anhydride and decyl (or) hexadecyl vinyl ether were obtained by radical polymerization. For hydrolysis of the polymers with a long alkyl side chain, heat treatment was necessary (60 C for several days in pure water). This resulted however in a reduction of average DP and probably in an enlargement of the initial distribution. Therefore, after hydrolysis, the polymer sample was fractionated with 2 1 acetonerbenzene as solvent and methanol as precipitant. 

Maleic anhydride grafting (cont.) poly(styrene-co-divinylbenzene), 694 poly(styrene-co-isobutylene), 675, 689 poly(styrene-co-nfialeic anhydride), 676, 679 poly(vinyl acetate), 676, 694 poly(vinyl acetate-co-vinyl fluoride), 678 poly(vinyl alkyl ethers), 675, 679, 692, 701 poly(vinyl chloride), 683, 692, 693, 695, 702 poly(vinylidene chloride), 691 poly(vinyl toluene-co-butadiene), 689 radical—initiated, 459-462, 464-466, 471, 475, 476 radiation—initiated, 459, 461, 466, 471, 474 redox-initiated, 476 rubber, 678, 686, 687, 691, 694 to saturated polymers, 459-466, 475, 476 solvents used 460-463, 465, 466, 469, 474-476 styrene block copolymers, 679 tall oil pitch, 678, 697 terpene polymers, 679, 700 thermally-initiated, 462, 464-467, 469, 476 to unsaturated polymers, 459, 466-474 vapor-phase techniques, 464, 474, 475 to wool fibers, 476 Maleic anhydride monomer acceptor for complex formation, 207-210 acetal copolymerization, 316 acetone CTC thermodynamic constants, 211 acetone photo-adduct pyrolysis, 195, 196 acetylacetone reaction, 235 acetylenic photochemical reactions, 193-196 acrylamide eutectic mixtures, 285 acylation of aromatic acids, 97 acylation of aromatics, 91, 92 acylation of fused aromatics, 92, 95, 97, 98 acylation of olefins, 99 acylation of phenols, 94-96 acylic diene Diels-Alder reactions, 104-111, 139 addition polymer condensations, 503-505 adduct with 2-cyclohexylimino-cyclopentanedi-thiocarboxylic acid, 51 adducts for epoxy resins curing, 507-510 adduct with 2-iminocyclopentanedithiocarboxylic acid, 51... 

Several vinyl monomers are used to prepare thermoplastics that are useful in certain adhesive applications. The most important vinyl resins for adhesives are polyvinyl acetate, polyvinyl acetals (butyral and formal), and polyvinyl alkyl ethers. PVC and copolymers of both vinyl chloride and vinyl acetate with other monomers, such as maleic acid esters, alkyl acrylates, maleic anhydride, and ethylene, are also used to produce solvent-based adhesives. ... 

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