acid anhydride


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acid anhydride

(ănhī`drīd, –drəd), chemical compound that reacts with water to form an acid (see acids and basesacids and bases,
two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Properties
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). Anhydrides of inorganic acids are usually oxides of nonmetallic elements. Carbon dioxide, CO2, is the anhydride of carbonic acid, H2CO3 . Nitrogen pentoxide, N2O5, is the anhydride of nitric acid, HNO3 . Phosphorus pentoxide, P2O5, is the anhydride of phosphoric acid, H3PO4 . Sulfur dioxide, SO2, is the anhydride of sulfurous acid, H2SO3 . Sulfur trioxide, SO3, is the anhydride of sulfuric acid, H2SO4 . Anhydrides of organic acids, like the acids themselves, contain the carbonyl group, CO. Organic anhydrides include acetic anhydride or ethanoic anhydride, (CH3C=O)2O, and benzoic anhydride, (C6H5C=O)2O.

acid anhydride

[′as·əd ‚an′hīd‚rīd]
(chemistry)
An acid with one or more molecules of water removed; for example, SO3 is the acid anhydride of H2SO4, sulfuric acid.
References in periodicals archive ?
1996), and among the different reagent used; acid chloride and acid anhydride are the most applied (Samaranayake and Glasser 1993) in both heterogeneous and homogeneous media.
The patent describes the use of sorbitol (easily derived from starch) as the polyhydric alcohol and the use of succinic acid anhydride as the polycarboxylic acid.
An acid anhydride with a chlorine content of 54.5%, it is used as a flame retardant and corrosin-resistant agent for unsaturated polyester and alkyd resins, and as a cross-linking agent in epoxy.
Resolution Specialty Materials LLC has been granted a patent for a waterborne acrylate-functionalized alkyd coating composition comprised of an acrylate-fnnctionalized alkyd resin comprising the reaction product of: 79-95% weight of an alkyd resin having an acid number of from 0-100 mg KOH/g; 2-8% of an acid anhydride; and 3-13% weight of a glycidyl acrylate, wherein the glycidyl moiety of the glycidyl acrylate is the reactive moiety and the reaction product contains reactive acrylate moieties, and wherein the weight percents are based on the total weight; at least one drier; and water.
Chlorendic anhydride is an acid anhydride with a chlorine content of 54.5% The product is used as a flame retardant and corrosion-resistant agent for unsaturated polyester and alkyd resins, and also as a crosslinking agent in epoxy.
* Succinic anhydride (SAA) for applications where a dibasic acid anhydride is desired.
DDSA (dodecenyl succinic anhydride) is offered for producing tougher, more flexible cured polymers; Succinic anhydride (SAA) is recommended for applications where a dibasic acid anhydride is desired; and HHPA (hexahydrophthalic anhydride) hardener is also recommended for curing epoxies.
An acid anhydride with a chloride content of 54.5%, it is used as a flame retardant and corrosion-resistant agent for unsaturated polyester and alkyd resins, and as a crosslinking agent in epoxy.
Summary: Acylated low molecular weight chitosans (LChA) were prepared from nucleophilic acylation of chitosan using acid anhydrides of short and medium chain length (4 - 10) to study the response of applied heat as a function of acyl chain length.
groups in the molecule with one or more saturated polycarboxylic acids or acid anhydrides; the polyester acrylic polymer containing less than 10 weight percent aromatic content and having a number average molecular weight of 560-2500 and a viscosity less than 1500 cps at 70 weight percent NVM solids dispersed in 30 weight percent styrene based on the total weight of the polymer and the styrene; the polyester acrylic polymer blended with a polymerizable vinyl monomer.
The infrared technique employed also allowed for the quantitative analysis of the compound types absorbing in the carbonyl region of the IR spectra including carboxylic acids, dicarboxylic acid anhydrides, 2-quinolone type.