Acids methacrylic

Synonyms 2-methylacrylic acid 2-methyl propenoic acid 

Methacrylic acid is used in the manufacture of methacrylate resins and plastics. 

Colorless liquid with an acrid and repulsive odor boils at 163°C (325.4°F) solidifies at 16°C (60.8°F) density 1.015 at 20°C (68 F) soluble in water and most organic solvents polymerizes readily. 

Methacrylic acid is a highly corrosive liquid. Contact with eyes can resnlt in blindness. Skin contact may prodnce bnms. No inhalation toxicity was observed in rats. Exposnre to its vapors may prodnce skin and eye irritation, which can be mild to moderate. A dermal LD50 valne in rabbits is 500 mg/kg. 

Combnstible liqnid flash point (open cnp) 76°C (I70°F) vapor pressnre 0.1 torr at 20°C (68°F). Fire-extingnishing agent water spray, alcohol foam, dry chemical, or CO2 nse a water spray to dilnte and flnsh the spill and to disperse the vapors. 

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The reaction of CO2 with allene using bis(dicyciohexylphosphino)ethane as a ligand affords a mixture of esters of methacrylic acid 17 and crotonic acid 18, and the lactone 19[12],... 

Polylacrylic Acid) and Poly(methacrylic Acid). Glacial acrylic acid and glacial meth-acrylic acid can be polymerized to produce water-soluble polymers having the following structures ... 

Amberlite DP-1 2.5 1.17 Methacrylic acid-DVB high resin capacity. Use pH >5. 

Amberlite IRC-50 3.5 1.25 Methacrylic acid-DVB. Selectivity adsorbs organic gases such as antibiotics, alkaloids, peptides, and amino acids. Use pH >5. 

VP copolymerization piNYL POLYTffiRS - N-VINYLAMIDE POLYTffiRS] pol 24) Methacrylic acid [71-49-4]... 

Processes have been developed whereby the oxygen is suppHed from the crystal lattice of a metal-oxide catalyst (5) (see Acrylonitrile Methacrylic acid AND derivatives). 

Poly(acrylic acid) and Poly(methacrylic acid). Poly(acryHc acid) (8) (PAA) may be prepared by polymerization of the monomer with conventional free-radical initiators using the monomer either undiluted (36) (with cross-linker for superadsorber appHcations) or in aqueous solution. Photochemical polymerization (sensitized by benzoin) of methyl acrylate in ethanol solution at —78° C provides a syndiotactic form (37) that can be hydrolyzed to syndiotactic PAA. From academic studies, alkaline hydrolysis of the methyl ester requires a lower time than acid hydrolysis of the polymeric ester, and can lead to oxidative degradation of the polymer (38). Po1y(meth acrylic acid) (PMAA) (9) is prepared only by the direct polymerization of the acid monomer it is not readily obtained by the hydrolysis of methyl methacrylate. 

Acrylics. Acetone is converted via the intermediate acetone cyanohydrin to the monomer methyl methacrylate (MMA) [80-62-6]. The MMA is polymerized to poly(methyl methacrylate) (PMMA) to make the familiar clear acryUc sheet. PMMA is also used in mol ding and extmsion powders. Hydrolysis of acetone cyanohydrin gives methacrylic acid (MAA), a monomer which goes direcdy into acryUc latexes, carboxylated styrene—butadiene polymers, or ethylene—MAA ionomers. As part of the methacrylic stmcture, acetone is found in the following major end use products acryUc sheet mol ding resins, impact modifiers and processing aids, acryUc film, ABS and polyester resin modifiers, surface coatings, acryUc lacquers, emulsion polymers, petroleum chemicals, and various copolymers (see METHACRYLIC ACID AND DERIVATIVES METHACRYLIC POLYMERS). 

Dehydrogenation of Propionates. Oxidative dehydrogenation of propionates to acrylates employing vapor-phase reactions at high temperatures (400—700°C) and short contact times is possible. Although selective catalysts for the oxidative dehydrogenation of isobutyric acid to methacrylic acid have been developed in recent years (see Methacrylic ACID AND DERIVATIVES) and a route to methacrylic acid from propylene to isobutyric acid is under pilot-plant development in Europe, this route to acrylates is not presentiy of commercial interest because of the combination of low selectivity, high raw material costs, and purification difficulties. 

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 ... 

Another textile use of acryUc polymers is fabric finishing, to impart a desired hand or feel, or to aid soil release, or for permanent-press features. Copolymers of acrylate esters with acryUc or methacrylic acid serve as thickeners for a variety of textile coating formulations (see Textiles, finishing). 

Anaerobic stmctural adhesives are typically formulated from acryhc monomers such as methyl methacrylate [80-62-6] C Hg02, and methacrylic acid [79-41-4] (see Acrylic ester polymers). Very often, cross-linking agents such as dimethacrylates are also added. A peroxide, such as cumene... 

Acryhc stmctural adhesives have been modified by elastomers in order to obtain a phase-separated, toughened system. A significant contribution in this technology has been made in which acryhc adhesives were modified by the addition of chlorosulfonated polyethylene to obtain a phase-separated stmctural adhesive (11). Such adhesives also contain methyl methacrylate, glacial methacrylic acid, and cross-linkers such as ethylene glycol dimethacrylate [97-90-5]. The polymerization initiation system, which includes cumene hydroperoxide, N,1S7-dimethyl- -toluidine, and saccharin, can be apphed to the adherend surface as a primer, or it can be formulated as the second part of a two-part adhesive. Modification of cyanoacrylates using elastomers has also been attempted copolymers of acrylonitrile, butadiene, and styrene ethylene copolymers with methylacrylate or copolymers of methacrylates with butadiene and styrene have been used. However, because of the extreme reactivity of the monomer, modification of cyanoacrylate adhesives is very difficult and material purity is essential in order to be able to modify the cyanoacrylate without causing premature reaction. 

In these equations I is the initiator and I- is the radical intermediate, M is a vinyl monomer, I—M- is an initial monomer radical, I—M M- is a propagating polymer radical, and and are polymer end groups that result from termination by disproportionation. Common vinyl monomers that can be homo-or copolymeri2ed by radical initiation include ethylene, butadiene, styrene, vinyl chloride, vinyl acetate, acrylic and methacrylic acid esters, acrylonitrile, A/-vinylirnida2ole, A/-vinyl-2-pyrrohdinone, and others (2). 

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 ... 

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