Methacrylic acid copolymer dispersion

Methacrylic acid copolymer Methacrylic acid copolymer dispersion Note that three separate monographs applicable to polymethacrylates are contained in the USPNF 23 see Section 9. Several different types of material are defined in the monographs. The PhEur 2005 contains four separate monographs applicable to polymethacrylates. 

Ammonio methacrylate copalymer ° Methacrylic acid capolymer Methacrylic acid copolymer dispersion ... 

Methacrylic acid copolymer dispersant, sludge lubricant oils Dimethylaminoethyl methacrylate dispersant, sludge oil drilling Cocoalkonium chloride dispersant, sludge petroleum PVP/eicosene copolymer PVP/hexadecene copolymer... 

Disperse Red 1 methacrylate-methacrylic acid copolymer, Disperse Red 1 metha-crylate-3-hydroxypropyl methacrylate copolymer, Disperse Red 1 methacrylate-polyethylene glycol monomethacrylate graft copolymer, Disperse Red 1 methacrylate-ethylene oxide graft copolymer H tactidty 61... 

The enteric protection properties of a methacrylate polymer were investigated with the use of naproxen tablets [56] enteric coated with an aqueous dispersion of methacrylic acid copolymer (EUDRAGIT L 30 D-55, USP NF type C). 

Naproxen sodium tablets were used in an in vivo-in vitro evaluation with four different polymeric dispersions, cellulose acetate phthalate (CAP), cellulose acetate trimellitate (CAT), 50 50 CAP/CAT, and methacrylic acid copolymer [64], The study indicated that coating material that dissolves at a more acidic pH in vitro (such as CAT at pH 4.5) will also dissolve at a more acidic pH in vivo (i.e., the coating dissolves higher up in the GI tract). In addition, it was found that aging did not markedly affect dissolution characteristics of CAT or methacrylic acid copolymer-coated tablets. 

B. Brogmann, K. Lehmann, Stability of enteric gelatin and starch capsules with aqueous dispersions of methacrylic acid copolymers AAPS Annual Congress, San Diego, 1994. 

K. Lehmann, B. Brogmann, C. J. Kenyon, J. R. Wilding, The in vivo behaviour of enteric naproxen tablets coated with an aqueous dispersion of methacrylic acid copolymer, S.T.P. Pharma Sci 7(6) 403-437 (1997). 

The USPNF 23 describes methacrylic acid copolymer as a fully polymerized copolymer of methacrylic acid and an acrylic or methacrylic ester. Three types of copolymers, namely Type A, Type B, and Type C, are defined in the monograph. They vary in their methacrylic acid content and solution viscosity. Type C may contain suitable surface-active agents. Two additional polymers, Type A (Eudragit RE) and Type B (Eudragit RS), also referred to as ammonio methacrylate copolymers, consisting of fully polymerized copolymers of acrylic and methacrylic acid esters with a low content of quaternary ammonium groups, are also described in the USPNF 23. A further monograph for an aqueous dispersion of Type C methacrylic acid copolymer is also defined see Section 9. 

Eastacryl30D, Kollicoat MAE 30 D, and KollicoatMAE 30 DP are also aqueous dispersions of the anionic copolymer based on methacrylic acid and ethyl acrylate. The copolymer also corresponds to USPNF 23 methacrylic acid copolymer. Type C. The ratio of free-carboxyl groups to ester groups is 1 1. Films prepared from the copolymers dissolve above pH... 

Details are given of the preparation of model ethyl acrylate-methacrylic acid copolymer latices by non-seeded semicontinuous emulsion copolymerisation. Polydispersity was examined using dynamic and static light scattering. Correlations between hydrodynamic volume and viscosity properties of the dispersions are discussed. The different character of the particle structure was confirmed by differences in particle disintegration after alkali addition or in the presence of methanol. 19 refs. 

Dispersion polymerisation of vinylpyridine was performed by nsing SBR as stabiliser in a mixture of DMF and tolnene to prodnce polymer particles. The effect of weight ratio of the solvents on particle size and dispersity is discussed. Details are also given of the preparation of monodisperse particles of vinylpyridine-methacrylic acid copolymers. 11 refs. 

Numerous recipes have been pubUshed, primarily ia the patent Hterature, that describe the preparation of acrylate and methacrylate homopolymer and copolymer dispersions (107,108). A typical process for the preparation of a 50% methyl methacrylate, 49% butyl acrylate, and 1% methacrylic acid terpolymer as an approximately 45% dispersion ia water begias with the foUowiag charges ... 

A waterborne system for container coatings was developed based on a graft copolymerization of an advanced epoxy resin and an acryHc (52). The acryhc-vinyl monomers are grafted onto preformed epoxy resins in the presence of a free-radical initiator grafting occurs mainly at the methylene group of the aHphatic backbone on the epoxy resin. The polymeric product is a mixture of methacrylic acid—styrene copolymer, soHd epoxy resin, and graft copolymer of the unsaturated monomers onto the epoxy resin backbone. It is dispersible in water upon neutralization with an amine before cure with an amino—formaldehyde resin. 

A salt of a polymer or copolymer of acrylic or methacrylic acid, in which the acid is neutralized with alkanolamines, alkylamines, or lithium salts [677], is suitable as a dispersing agent. 

A nonpolluting dispersing agent for drilling fluids [217-219] has been described. The agent is based on polymers or copolymers of unsaturated acids, such as acrylic acid or methacrylic acid, with suitable counter ions. 

Copolymer particles can also be prepared from HIPEs [159]. Thus, a HIPE dispersed phase consisting of styrene and methacrylic acid was polymerised to give copolymers. The surface concentration of carboxylic acid groups increased linearly with concentration of methacrylic acid in the feed. The small amount of water present in the concentrated emulsion, relative to conventional emulsion polymerisation, reduces the loss of methacrylic acid, which is highly water-soluble. 

Poly(acrylic acid) is water soluble. Because of its water solubility and its ability to increase the viscosity of water, it is used as a thickener. It is also a good flocculent for sewage treatment and is added as a pigment dispersant in latex paints, and is used in binders and adhesives. Polymers and copolymers containing acrylic or/and methacrylic acid are manufactured at a rate of about 2,000,000 metric tons yearly. 

Similarly, cobalt(ll)-pyridine (CoPy) complexes bound to copolymers of styrene and acrylic or methacrylic acid, cross-linked with divinylbenzene, catalyze the autoxidation of tetralin dispersed in water at 50°C and 1 bar.45 The rate of oxidation with the colloidal CoPy catalyst was twice as fast as with homogeneous CoPy and nine times as fast as with cobalt(II) acetate in acetic acid. 

The stable polymer dispersions with small-sized polymer particles of diameter >60 nm were prepared by dispersion copolymerization of PEO-MA macromonomer with styrene, 2-ethylhexyl acrylate, acrylic and methacrylic acids, and butadiene at 60 °C [79]. The particle size was reported to decrease with increasing macromonomer fraction in the comonomer feed. Besides, it varied with the type of the classical monomer as a comonomer. Tg of polymer product was found to be a function of the copolymer composition, the weight ratio macromonomer/monomer, and monomer type and varied from 50.6 to 220.4 °C. 

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