Methylmethacrylate from methacrylic acid

FIGURE 6.24 Experimental observation of dimensional changes during the release of oxpre-nolol HC1 from poly(methylmethacrylate-co-methacrylic acid) beads. [Graph reconstructed from data by Kim and Lee, Pharm. Res., 9, 1268 (1992).]... 

Formulations for acryHc copolymers involve monomers such as acryHc acid [79-10-7], methacrylic acid [79-14 ], or esters of these acids. Formation of a copolymer from a methylmethacrylate ester (3), where DVB serves as the cross-linker, gives the stmctures ... 

The current industrial production of methylmethacrylate by the acetone-cyanohydrin process suffers from a number of drawbacks, which make it environmentally unfriendly. In particular, it makes use of a very toxic reactant (HCN) and intermediate (acetone cyanohydrin), and coproduces large amounts of impure ammonium sulphate, contaminated with organic compounds. Among the several alternative synthetic routes which have been proposed, particularly interesting from both the practical and scientific points of view is the single-step oxidation of isobutane to methacrylic acid, intermediate in the synthesis of methylmethacrylate. Several industrial companies have studied this reaction (and the selective oxidation of propane to acrylic acid, as well), and it has been established that the most active and selective catalysts are those which are based on Keggin-type polyoxometalates (POM s), containing phosphorus and molybdenum as the main components [1-18]. 

Batch Di (3-pentyl) Malate Process Acetaldehyde from Acetic Acid Ethylene by Oxidative Dehydrogenation of Ethane Butadiene to n-Butyraldehyde and n-Butanol Methacrylic Acid to Methylmethacrylate Coproduction of Ethylene and Acetic Acid from Ethane Methylmethacrylate from Propyne Mixed-C4 Byproduct Upgrade Hydrogen Peroxide Manufacture Di-tem fljy-butyl-peroxide Manufacture Vinyl Acetate Process PM Acetate Manufacture Propoxylated Ethylenediamine Petroleum Products Fuel Additives for Cleaner Emissions Gas Manufacture... 

Figure 1.16. Fractional release rate of prednisolone from a hydrogel formed by cross-linked PEO and poly(methacrylic acid-c6>-methylmethacrylate) versus time. The effects of pH changes on the release rate are also shown (data from ref. (217))...

Carboxy-terminated nitrile rubber Elastomeric copolymer from ethylene and ethyl acrylate Ethylene-glycidyl methacrylate copolymer Copolymer from ethylene and methacrylic acid Copolymer from ethylene and methylmethacrylate... 

Carbon nanofibers derived from electrospun PAN are long (centimeter long nanofibers are fabricated routinely), continuous and relatively well aligned, hence they are ideal for strengthening, stiffening and toughening of polymers [10]. PAN homopolymer has been hardly used because of its poor properties and processability, so the monomers such as acrylic acid (AA), methacrylic acid (MAA) and methylmethacrylate (MMA) have been widely added to PAN monomer to form high performance carbon fibers [11]. 

Classical poly(methylmethacrylate)-type AR properties are far from those necessary for a definitive filling material. They do not adhere to hard dental tissues. As a result their receipts included monomers (methacrylic acid) to improve ad-... 

The monomers used for preparation of acrylic polymers vary in nature and can generally be classified as hard (such as methylmethacrylate, styrene and vinyl acetate) or soft (such as ethyl acrylate, butyl acrylate, 2-ethyl hexyl acrylate). Reactive monomers may also have hydroxyl groups (such as hydroxy ethyl acrylate). Acidic monomers such as methacrylic acid are also reactive and may be included in small amounts in order that the acid groups may enhance pigment dispersion. The practical coating systems are usually copolymers of hard and soft monomers. The polymer hardness is characterized by its glass transition temperature, Tg. The Tg (K) of the copolymer can be estimated from the Tg of the individual Tg (K) of the homopolymers with weight fractions and Wj,... 

Figure 3.20 Pyrograms of polymethylmethacrylates and some acid copolymers after propylation. Polymethylmethacrylate containing the following amoimts of copolymerised acid A 10% methacrylic B 1% methacrylic acid C 10% acrylic acid D 1 % acrylic acid E no acid elution times methylmethacrylate 9 min, propyl acrylate 15 min, propylmethacrylate 28 min. Reprinted with permission from J.L. Sharp and G. Paterson, Analyst, 1986, 105, 1250, 517. 1986, RSC) [41]...

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