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Methacrylates
Methacrylates are derivatives of methacrylic acid. * Methyl methacrylate * Ethyl methacrylate * Butyl methacrylate * Hydroxyethyl methacrylate * Glycidyl methacrylate Glycidyl methacrylate (GMA) is an ester of methacrylic acid and glycidol. Containing both an epoxide and an acrylate groups, the molecule is bifunctional. It is a common monomer used in the production of epoxy resins. While typical home epoxies c ... {{set index Carboxylate anions Monomers Methacrylate esters ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methyl Methacrylate
Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (MAA), is a monomer produced on a large scale for the production of poly(methyl methacrylate) (PMMA). Production and properties Given the scale of production, many methods have been developed starting from diverse two- to four-carbon precursors.. Two principal routes appear to be commonly practiced. Cyanohydrin route The compound is manufactured by several methods, the principal one being the acetone cyanohydrin (ACH) route. ACH is produced by condensation of acetone and hydrogen cyanide. The cyanohydrin is hydrolyzed in the presence of sulfuric acid to a sulfate ester of the methacrylamide. Methanolysis of this ester gives ammonium bisulfate and MMA. Although widely used, the ACH route coproduces substantial amounts of ammonium sulfate. :(CH3)2CO + HCN → (CH3)2C(OH)CN :(CH3)2C(OH)CN + H2SO4 → (CH3)2C(OSO3H)C(O)NH2. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Methacrylic Acid
Methacrylic acid, abbreviated MAA, is an organic compound. This colorless, viscous liquid is a carboxylic acid with an acrid unpleasant odor. It is soluble in warm water and miscible with most organic solvents. Methacrylic acid is produced industrially on a large scale as a precursor to its esters, especially methyl methacrylate (MMA), and to poly(methyl methacrylate) (PMMA). MAA occurs naturally in small amounts in the oil of Roman chamomile. Production In the most common route, methacrylic acid is prepared from acetone cyanohydrin, which is converted to methacrylamide sulfate using sulfuric acid. This derivative in turn is hydrolyzed to methacrylic acid, or esterified to methyl methacrylate in one step. Another route to methacrylic acid starts with isobutylene, which obtainable by dehydration of ''tert''-butanol. Isobutylene is oxidized sequentially to methacrolein and then methacrylic acid. Methacrolein for this purpose can also be obtained from formaldehyde and ethylene. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ethyl Methacrylate
Ethyl methacrylate is the organic compound with the formula C2H5O2CC(CH3)=CH2. A colorless liquid, it is a common monomer for the preparation of acrylate polymers.. It is typically polymerized under free-radical conditions. Ethyl methacrylate was first obtained by treating 2-hydroxyisobutyric acid with phosphorus pentachloride in an apparent dehydration reaction.{{cite journal, journal=Justus Liebigs Annalen der Chemie, volume= 136, page= 12, title=Untersuchungen über Säuren aus der Acrylsäure-Reihe; 1) Umwandlung der Säuren aus der Milchsäure-Reihe in die der Acrylsäure-Reihe, author=E. Frankland, B. F. Duppa, year=1865, doi=10.1002/jlac.18651360102 Environmental issues and health hazards The acute toxicity of the related butyl methacrylate is the LD50 is 20 g/kg (oral, rat). Acrylate esters irritate the eyes and can cause blindness. See also * Methyl methacrylate * Butyl methacrylate Butyl methacrylate is the organic compound with the formula C4H9O2CC(CH3)=CH2. A c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Butyl Methacrylate
Butyl methacrylate is the organic compound with the formula C4H9O2CC(CH3)=CH2. A colorless liquid, it is a common monomer for the preparation of methacrylate polymers.. It is typically polymerized under free-radical conditions.{{cite journal, title=Controlled Radical Polymerization of Methacrylic Monomers in the Presence of a Bis(ortho-chelated) Arylnickel(II) Complex and Different Activated Alkyl Halides, last1=Granel, C., last2=Dubois , first2=Ph., last3=Jérôme , first3=R., last4=Teyssié , first4=Ph., journal=Macromolecules, year=1996, volume=29, issue=27, page=8576–8582, doi=10.1021/ma9608380, bibcode=1996MaMol..29.8576G Health hazards In terms of the acute toxicity of butyl methacrylate, the LD50 is 20 g/kg (oral, rat). It is an irritant to the eyes and can cause blindness. See also * Methacrylic acid * Methyl methacrylate Methyl methacrylate (MMA) is an organic compound with the formula CH2=C(CH3)COOCH3. This colorless liquid, the methyl ester of methacrylic acid (M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydroxyethyl Methacrylate
Hydroxyethylmethacrylate (also known as glycol methyacrylate) is the organic compound with the chemical formula . It is a colorless viscous liquid that readily polymerizes. Hydroxyethylmethacrylate is a monomer that is used to make various polymers. Synthesis Hydroxyethylmethacrylate was first synthesized around 1925. Common methods of synthesis are: * reaction of methacrylic acid with ethylene oxide; * esterification of methacrylic acid with a large excess of ethylene glycol. Both these methods give also some amount of ethylene dimethacrylate. During polymerization of hydroxyethylmethacrylate, it works as crosslinking agent. Properties Hydroxyethylmethacrylate is completely miscible with water and ethanol, but its polymer is practically insoluble in common solvents. Its viscosity is 0.0701 Pa⋅s at 20°C and 0.005 Pa⋅s at 30°C. During polymerization, it shrinks by approximately 6%. Applications Contact lenses In 1960, O. Wichterle and D. Lím described its use in synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycidyl Methacrylate
Glycidyl methacrylate (GMA) is an ester of methacrylic acid and glycidol. Containing both an epoxide and an acrylate groups, the molecule is bifunctional. It is a common monomer used in the production of epoxy resins. While typical home epoxies contain diglycidyl ether of bisphenol A (DGEBA), glycidyl methacrylate is instead used to provide epoxy functionalization to polyolefins and other acrylate resins. Glycidyl methacrylate is produced by several companies worldwide, including Dow Chemical. It is used to prepare a range of composites.{{cite journal , doi=10.1038/nmat1890, title=Multifunctional chondroitin sulphate for cartilage tissue–biomaterial integration , year=2007 , last1=Wang , first1=Dong-An , last2=Varghese , first2=Shyni , last3=Sharma , first3=Blanka , last4=Strehin , first4=Iossif , last5=Fermanian , first5=Sara , last6=Gorham , first6=Justin , last7=Fairbrother , first7=D. Howard , last8=Cascio , first8=Brett , last9=Elisseeff , first9=Jennifer H. , journal=N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboxylate Anions
In organic chemistry, a carboxylate is the conjugate base of a carboxylic acid, (or ). It is an ion with negative charge. Carboxylate salts are salts that have the general formula , where M is a metal and ''n'' is 1, 2,...; ''carboxylate esters'' have the general formula (or ). R and R′ are organic groups; R′ ≠ H. Synthesis Carboxylate ions can be formed by deprotonation of carboxylic acids. Such acids typically have p''K''a of less than 5, meaning that they can be deprotonated by many bases, such as sodium hydroxide or sodium bicarbonate. :RCOOH + NaOH -> RCOONa + H2O Resonance stabilization of the carboxylate ion Carboxylic acids easily dissociate into a carboxylate anion and a positively charged hydrogen ion (proton), much more readily than alcohols do (into an alkoxide ion and a proton), because the carboxylate ion is stabilized by resonance. The negative charge that is left after deprotonation of the carboxyl group is delocalized between ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monomers
In chemistry, a monomer ( ; ''mono-'', "one" + '' -mer'', "part") is a molecule that can react together with other monomer molecules to form a larger polymer chain or three-dimensional network in a process called polymerization. Classification Monomers can be classified in many ways. They can be subdivided into two broad classes, depending on the kind of the polymer that they form. Monomers that participate in condensation polymerization have a different stoichiometry than monomers that participate in addition polymerization: : Other classifications include: *natural vs synthetic monomers, e.g. glycine vs caprolactam, respectively *polar vs nonpolar monomers, e.g. vinyl acetate vs ethylene, respectively *cyclic vs linear, e.g. ethylene oxide vs ethylene glycol, respectively The polymerization of one kind of monomer gives a homopolymer. Many polymers are copolymers, meaning that they are derived from two different monomers. In the case of condensation polymerizations, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
