Carboxylated polyester resin

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). 

Of particular importance in describing the difference between these two families of resins are the locations of die reactive unsaturation. In the polyester resin, these groups are located along the backbone of die polymer with terminal hydroxyl or carboxylic acid groups. The vinyl ester resins contain no significant acidity but terminate in reactive vinyl ester groups. Because of the location of these reactive sites, the vinyl ester resins will homopolymerize as well as coreact with various vinyl monomers. 

Oxidation. Ketones are oxidized with powerful oxidizing agents such as chromic or nitric acid. During oxidation, carbon—carbon bond cleavage occurs to produce carboxylic acids. Ketone oxidation with hydrogen peroxide, or prolonged exposure to air and heat, can produce peroxides. Concentrated solutions of ketone peroxides (>30%) may explode, but dilute solutions are useful in curing unsaturated polyester resin mixtures (see... 

To overcome these drawbacks, in recent years much attention has been paid to the development of resins which cem be f2d ricated with the same processes as those for conventional polyester resins, but having superior properties. Vinyl ester resins are the result of such development efforts (4-6). Vinyl ester resins are addition products of Vcurious epoxide resins and ethylenically unsaturated mono-carboxylic acids ( ). It condsines the excellent mechcuiical, chemical cuid solvent resistemce of epoxy resins with the properties found in the unsaturated polyester resins. In general, the cured vinyl ester resin has physical properties superior to the cured conventional ester resin, particulcurly corrosion resistcuice. This arises from the differences in the number and arremgement of polar groups such as ester and hydroxyl groups eind ccurbon-to-ccirbon double bonds present in the polymer chains. 

For laboratory use and, perhaps, for small-volume production, another first stage can be added. Microreactors, which require much less solvent, are being studied for fluorina-tion,6 DNA chips, and other uses.7 A variation on item 2 is the use of a polyhydroxyester based on aromatic epoxy resins and aliphatic carboxylic acids to reduce the loss of styrene from unsaturated polyester resins by 95-99%.8... 

In general, polyester resins are synthesized by the reaction between carboxylic acids and alcohols, with three or more reactive groups. Recently, unsaturated polyesters were incorporated in various ways to produce terminal, pendant, and internal double bonds [57-59]. In the case of unsaturated polyesters, maleic anhydride is most commonly used to produce internal unsaturation. The double bond present on unsaturated polyester reacts with a vinyl monomer, mainly styrene, resulting in a 3D crosslinked structure. This structure acts as a thermoset. The crosslinking is initiated through an exothermic reaction involving an organic peroxide, such as methyl ethyl ketone peroxide or benzoyl peroxide (Fig. 3.18). 

DIN 53183 defines an alkyd resin as follows Alkyd resins are synthetic polyester resins produced by esterifying polyhydric alcohols with polybasic carboxylic acids. At least one of the alcohols must be trihydric or higher. Alkyd resins are always modified with natural fatty acids or oils and/or synthetic fatty acids. In order to obtain particular application technology properties, alkyd resins may be additionally modified with compounds such as resin acids, benzoic acid, styrene, vinyltoluene, isocyanates, acrylic, epoxy, or silicone compounds. ... 

Polyester resins are condensation products of di- or polyfunctional monomers containing hydroxyl groups and carboxyl groups. The development of saturated polyesters began in 1901 with Glyptal resins , formed from glycerol and phthalic anhydride (Smith, United States). Soluble resins obtained with fatty acids were first employed in 1925. Alkyd resins formed from unsaturated fatty acids can be cured by atmospheric oxidation (see Section 2,6). Other unsaturated polyester resins are discussed in Section 2.8. 

Polyester resins for waterborne paints mostly contain anionic groups (e.g., carboxyl groups) and become water soluble after amine neutralization. Waterborne paints based on polyesters also contain cosolvents, preferably glycol ethers. Powder coatings based on low molecular mass resins are solvent-free, like radiation-curable polyester paints. 

Alkylated melamine-, urea-, and benzoguanamine-formaldehyde resins are the principal cross-linking agents in many industrially applied baked coatings. They are combined with acrylic, alkyd, epoxy, and polyester resins. The amide, hydroxyl, or carboxyl groups of these backbone polymers are used as functional sites for reaction with the amino resin. 

Chem. Descrip. Carboxyl-terminated polyester resin Uses Powd. coating resin for interior applies., appliances, automotives, elec./electronics, general metal, machinery, equip., metal furniture/fix-tures, low gloss hybrids... 

MP PDEG in the composition of the polyester resin has end hydroxyl and carboxyl groups capable of interacting with the isocyanate groups. To prevent the chemical interaction of the individual IPN networks, the MP PDEG end groups were pre-blocked with a monofunctional isocyanate (phenyl isocyanate) later this reaction was excluded with almost no effect upon the adhesive properties. 

The condensation reaction between carboxylic acid and alcohol to form an ester and water is a fundamental chemical reaction, and has been known at least from when the term organic chemistry was coined in the early nineteenth century. From the mid- to late-nineteenth century, studies were carried out on the reactions of compounds containing more than one acid group with compounds containing more than one hydroxyl group. These studies produced the first polyester resins, and lead to the development in the early twentieth century of various thermoset polymers such as the alkyd resins. 

The presence of reactive sites such as double bonds, hydroxyl and carboxyl groups and phenyl rings in aromatic anhydride and ester linkages all provide tremendous potential for the modification of oil-modified polyester. Epoxy resins are considered to be polyols, which react with the carboxylic functions of polyester resin. The modification of oil-modified polyesters with epoxy resins results in products with excellent adhesion properties and improved water and chemical resistance. Epoxy modified polyesters are less expensive than epoxy resins. 

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