Polycarboxylic acid anhydride

Imide-Modified Isocyanurate Foams. The imide linkage is a thermally stable linkage, and therefore, imide-modified isocyanurate foams have higher thermal stability and flame retardance than urethane-modified isocyanurate foams. R. Grieve (114) prepared such foams in a one-shot process by reacting a polycarboxylic acid anhydride with an organic polyisocyanate in the presence of a catalytic amount of a monomeric homocyclic polyepoxide and a tertiary amine. 

Polycarboxylic acid anhydrides by oxidation of aromatic compounds, e.g.—phthalic anhydride from naphthalene or o-xylene and also maleic anhydride from benzene... 

The potential combinations and applications of starches is almost limitless. For example, the esterification of an oxidized, crosslinked, thin boiling starch with a polycarboxylic acid anhydride forms a modified, derivatized starch often used as a warp size in the textile industry (19). This combination of modifications demonstrates the variety of changes that can be made to produce a unique gum. As new modifications and techniques are developed, the number of combinations continues to increase, and the potential of developing new, beneficial modified starches is assured. 

Numerous methods of modifying epoxidized polydienes aim at introducing into the structure of these resins some unsaturated groups with increased reactivity. One of these is the reaction of oxiranic groups with unsaturated carboxylic acids (acrylic, methacrylic, itaconic) [222] and, more frequently, with acrylic hydroxy esters, like 2-hydroxyethylmethacrylate, 2-hydroxyethylaciylate, and especially reaction products of the semiester type obtained by the reaction between hydroxyalkylmethacrylates and polycarboxylic acid anhydrides [223,224]. 

Acid Anhydrides. Symmetrical anhydrides of monocarboxylic acids, when unsubstituted, are named by replacing the word acid by anhydride. Anhydrides of substituted monocarboxylic acids, if symmetrically substituted, are named by prefixing bis- to the name of the acid and replacing the word acid by anhydride. Mixed anhydrides are named by giving in alphabetical order the first part of the names of the two acids followed by the word anhydride, e.g., acetic propionic anhydride or acetic propanoic anhydride. Cyclic anhydrides of polycarboxylic acids, although possessing a... 

The diacids are characterized by two carboxyHc acid groups attached to a linear or branched hydrocarbon chain. AUphatic, linear dicarboxyhc acids of the general formula HOOC(CH2) COOH, and branched dicarboxyhc acids are the subject of this article. The more common aUphatic diacids (oxaUc, malonic, succinic, and adipic) as weU as the common unsaturated diacids (maleic acid, fumaric acid), the dimer acids (qv), and the aromatic diacids (phthaUc acids) are not discussed here (see Adipic acid Maleic anhydride, maleic acid, and fumaric acid Malonic acid and derivatives Oxalic acid Phthalic acid and OTHERBENZENE-POLYCARBOXYLIC ACIDS SucciNic ACID AND SUCCINIC ANHYDRIDE). The bihinctionahty of the diacids makes them versatile materials, ideally suited for a variety of condensation polymerization reactions. Several diacids are commercially important chemicals that are produced in multimillion kg quantities and find appHcation in a myriad of uses. 

By depolymerizing PET waste with a polyol and subsequently condensing the oligomeric product with a polycarboxylic acid or anhydride, polyester resins are produced which have wide industrial applications. Depending on the polyol and polycarboxylic acid or anhydride used, saturated resins, alkyd resins, or unsaturated resins are obtained. PET wastes have been used for the production of alkyd resins in water thinnable paints. The materials obtained from the reaction of PET with a mixture of fatty acids high in linoleic acid content and trimethylolethane have been used in the preparation of water-dispersible coatings. Products of the depolymerization of PET with trimethylolpropane and pentaerythritol are used in the manufacture of high-solids paints. In the first step, PET is depolymerized with trimethylopropane and pentaerythritol at temperatures of 230-240°C. The final paint compositions contain 30-50% of PET depolymerization products.12... 

There is an interesting technique which makes it possible to introduce carboxylic acid groups into a copper phthalocyanine structure by an economical route. Carrying out the phthalic anhydride/urea process in the presence of a small amount of trimellitic acid or another benzene polycarboxylic acid will afford a car-boxylated pigment. 

The mechanism of high-temperature, base-catalyzed esterification involves cyclic anhydride formation by the polycarboxylic acid, followed by base-catalyzed reaction of anhydride groups with cellulosic hydroxyls. Fumaric acid, which cannot form a cyclic anhydride because of the trans arrangement of the two carboxyl groups, fails to react with cotton in the presence of weak bases and heat. 

Curing of epoxy resins by polycarboxylic acids and cyclic anhydrides is also important in applications, but it is much less understood due to more complex reaction mechanism. Also, the statistical treatment is less developed and partly requires a revision. In this section, the statistics of curing of epoxy resins with polycarboxylic acids and cyclic anhydrides is discussed. 

Fatty alcohol can be fractionated to separate the C8-C10 fraction, known as plasticizer range alcohol, and the C12-C18, known as the detergent range alcohol. The plasticizer range alcohol is a liquid with good dissolving power. It can be used in a limited way as a solvent for printing inks and lacquers. Esterification with a polycarboxylic acid, such as phthalic anhydride, yields an excellent plasticizer especially for PVC. 

This chapter is concerned with the cathodic reduction of carboxylic acids and their derivatives, that is, esters, amides, anhydrides, acyl halides, hydrazides, nitriles, and corresponding thio derivatives. Cyclic derivatives of substituted carboxylic and polycarboxylic acids, such as lactones, lactams, imides, and anhydrides, are also included. Only those transformations in which the functional group itself is involved are discussed. Reductive coupling of carboxylic acids and derivatives is covered in Chapter 22, and there is some overlap with reduction of heterocycles in Chapter 18. 

Anhydrides of acyclic polycarboxylic acids 348 Epoxy compounds, general... 

Benzoic acid prepared catalytically from phthalic anhydride may contain certain undesirable compounds, tars, and coloring materials and must of necessity be purified in some cases to obtain a marketable product. Naphthoquinone impurities are reduced to naphthohydroquinones by treatment of the product with sulfur dioxide or sodium bisulfite at 40° to 50° C. for 3 to 4 hours. Any phthalic anhydride remaining is converted to phthalic acid at the same time. Leaching with water is used to remove the reduced impurities.72 Unconverted phthalic acid may also be separated from benzoic by treatment of the mass with sodium carbonate so as to convert the polycarboxylic acid into a primary salt while leaving the mono-carboxylic acid unreacted. Solvent leaching is then used to separate the salt from the acid.78 Colored impurities in benzoates from synthetic benzoic acid may be removed by oxidation with potassium permanganate.71... 

Permanent-press fabrics are often cured with TV-methy-lol compounds, such as 4.18, and tend to release formaldehyde after the cure. (Formaldehyde [a carcinogen] from various formaldehyde resins is a problem in some homes.115) These can be replaced with polycarboxylic acids, such as the 1,2,3,4-butanetetracarboxylic acid (4.19), which cure via the cyclic anhydride.116 Both dyeing and durable-press treatments can be combined in a single step, if desired.117... 

The reactive methods of compatibili2ation developed subsequently allowed the second generation Noryl (a blend of PPO with PA) to be developed. The compositions claimed usually cover 30-70% of each of the main ingredients, PPO and PA, with additionally up to four parts of such modifier as polycarboxylic acid, trimellitic anhydride acid chloride, quinine, oxidized polyolefin wax, and so on. In most cases, PA forms a matrix with spherical inclusions of PPO acting as compatibilized low-density filler. 

DeTinltlon Polymer consisting of partial butyl ester of the polycarboxylic acid formed from vinyl methyl ether and maleic anhydride Empirical (C H,805) ... 

Another important group are the polyamide imides and polyimides. The substitution of tricarboxylic acid anhydride for dicarboxylic acids during synthesis results in thermally more stable polyamide imides. The polycondensation reaction proceeds in two steps, with the solution of the intermediate polycarboxylic acid used in applications where the final product can be generated by a thermal or baking process. Uses include heat-resistant wire and cable coatings. The basic synthesis of polyamide imides is as follows ... 

TTiere are two processes for making alkyd resins, the fatty acid process, in which the three components are heated together at around 200 C, and the monoglyceride process in which the oil and polyol are first heated together to form partial glycerides, which are then reacted with the polycarboxylic acid or its anhydride. In the latter case the glycerol of the oil forms part of the total polyol component. 

Some additives, or combinations of additives, have been disclosed as impact or heat shock resistance promoters for cyanoacrylates. For example, a variety of alkyl and aryl polycarboxylic acids and anhydrides have been described as impact resistance promoters. The property measured was impact strength on steel according to ASTM D-950. In this test, an improvement in adhesion will result in an improved impact strength. These formulations show little or no improvement over a control in tests for fracture toughness. In other words, these additives are adhesion promoters, not... 

Some of the adhesion promoters listed in the previous section are also moisture resistance promoters. For example, the polycarboxylic acids and their anhydrides of ref. 79 were alleged to improve moisture resistance, but no evidence was presented to back this claim. Also, phthalic anhydride was shown to impart improved moisture resistance to ethyl cyanoacrylate stainless steel-stainless steel bonds. 

Metal acetylacetonates are covalently bound by the reaction of crosslinked chloromethyl-ated polystyrene (DMF, 100 °C) under formation of 7 [104]. Rare earth Eu(III)-complexes of l-carboxy-8-naphthoyl bound covalently at polystyrene 8 are obtained by Friedel-Crafts acylation of the corresponding naphthalenetetracarboxylic acid anhydride with the polymer followed by reaction with Eu [105]. The luminescence properties of lanthanide ions with polycarboxylates were investigated in detail [106]. The effects of the conformation of polymer chains on electron transfer and luminescence behaviour of Co(II)-, Co(III)-ethylenediamine complexes at polycarboxylates were studied [107]. 

In recent years the availability of several aromatic polycarboxylic acids has been exploited in specialty alkyd resin preparations [57, 58]. For example, trimellitic acid-based alkyds are used in alkyd-melamine enamels and acrylic lacquers [57]. Isophthalic acid can be used alone or in conjunction with trimellitic anhydride or phthalic anhydride [59]. Pyromellitic acid and pyromellitic anhydride have also been suggested as partial replacements for phthalic anhydride in long or short oil alkyds to give more water-resistant (also caustic- and gasoline-resistant) coatings [60]. 

Polycarboxylic acid or anhydride Polyol Oil Catalyst Temp. CF) Time (hr) Acid no. Ref. 

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