Resin polyester

Polyester resins, reinforced with glass fibers, are used widely in the construction of process equipment. Some physical and mechanical properties are presented in Table 3.48. Table 3.49 lists various materials used as filler and the properties they impart to different plastics. 

The biphenol polyesters, being considerably more expensive than isophtha-leics, have better chemical resistance to strong alkaline solutions and oxidizing solutions. For about the same price as the biphenols, the 

Property Polyester/ Glass Mat Polyester/ Woven Glass Qoth Epoxy/ Woven Glass Cloth Epoxy/ Filament Wound Glass Rovings 

Filler Material Qiemical Resistance Heat Resistance Electrical Insulation Impact Strength Tensile Strength 

The growth of Glyptal resins was hampered by hi cost and insufficient supply of phthalic anhydride. Tffis problem was solved in 1936 by the development of the Gibbs catalytic process for the oxidation of naphthalene. R.H. Kienle of General Electric Co. modified Glyptal resins with drying oils and coined the named alkyd . Kienle s patent for alky resins obtained in 1933 was declared invalid in 1935 but the acronym alkyd continues to be used to describe this major coating resin. 

Glycyl maleates were described by D. Vorlander in 1894 and synthesized by W.H. Carothers in 1929. Carlton Ellis was granted a patent for the polymerization of a solution of glycol maleate in vinyl acetate in 1937. Because of its volatility, the vinyl acetate was replaced later by styrene and these tems were used to impregnate fiberglass for the production of polyester composites. The annual production of unsaturated polyester resins in the U.S. is 1.4 billion pounds. 

Unsaturated polyester resins are the product of an esterification reaction between dibasie organic acids (or anhydrides) and a dihydric alcohol (glycol) with the formation of H2O. One of these groups, generally the acid, contributes the unsaturation to enable erosslinking to take 

During esterification, maleic acid readily isomerizes, when reacting with ethylene glycol, into the ira 5-isomer (fumaric add), with a conversion of about 95%. Hence in this instance, there would be no advantage using fumaric acid in place of maleic anhydride, unless 100% of the ira 5-configuration is required for some specific purpose. 

The product is dissolved in a monomer containing vinyl unsaturation such as styrene, with its pendant vinyl group. 

The monomer must be non-aromatic, otherwise crosslinking will not occur. The polyester and reactive diluent crosslink with heat and/or free radical initiation into a soKd non-melting network. 

Saturated acids can also be used, which can contain an aromatic nucleus and have no pendant double bonds that would react with a peroxide catalyst. Phthalic add exists in three isomeric forms and one of the isomers, orthophthalic acid, can form an anhydride and is widely used in this form  

The basic materials used to make a polyester resin are a dibasic organic acid or anhydride and a dihydric alcohol. 

Catalyst or initiators for unsaturated polyester resin system consist of 

Typical properties of the three principal types are listed in Table 4.1. Resins 

These three groups form the basis of most resins. Many blends and variations are available depending upon, inter alia, the nature of the application and the process used. 

A major difference between the groups is their elongation at break, particularly as a high elongation aids toughness and impact properties (section 6.2). 

Resins with similar heat distortion temperatures are shown in Table 4.1. However, higher temperature versions of these resins are also available, for example, iso-polyesters have the highest HDT (c.l30°C), iso-NPG, somewhat lower (c.llO°C) and ortho-polyesters the lowest (c.lOO°C). 

Post curing at or above the required temperature of use may be necessary, and indeed required, depending upon the type of application (Table 9.7). 

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Used as fibres, particularly in textiles and film. Many other polyester polymers are of importance, e.g. unsaturated polyester resins from phthalic anhydride, propylene glycol and maleic anhydride used with reinforcement in boats, cars, etc. (alkyd resins). U.S. production 1983 1-7 megatonnes. 

About 2 X 10 Ib/year of 1 2 epoxypropane is produced in the United States as an intermediate in the preparation of various polymeric materials including polyurethane plastics and foams and polyester resins A large fraction of the 1 2 epoxypropane is made from propene by way of its chlorohydrm... 

Organic peroxides are used extensively for the curing of unsaturated polyester resins and the polymerization of monomers having vinyl unsaturation. The —O—O— bond is split into free radicals which can initiate polymerization or cross-linking of various monomers or polymers. 

Alkyds are formulated from polyester resins, cross-linking monomers, and fillers of mineral or glass. The unsaturated polyester resins used for thermosetting alkyds are the reaction products of polyfunctional organic alcohols (glycols) and dibasic organic acids. 

Polyester film Polyester plasticizers Polyester polyol Polyester polyols Polyester resins... 

ALCOHOLS,HIGHERALIPHATIC - SURVEY AND NATURALALCOHOLSMANUFACTURE] (Voll) Unsaturated polyester resins... 

Almost all of the OX that is recovered is used to produce phthaUc anhydride. PhthaUc anhydride is a basic building block for plasticizers used in flexible PVC resins, for polyester resins used in glass-reinforced plastics, and for alkyd resins used for surface coatings. OX is also used to manufacture phthalonitrile, which is converted to copper phthalocyanine, a pigment. 

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). 

Bisphenol A. One mole of acetone condenses with two moles of phenol to form bisphenol A [80-05-07] which is used mainly in the production of polycarbonate and epoxy resins. Polycarbonates (qv) are high strength plastics used widely in automotive appHcations and appHances, multilayer containers, and housing appHcations. Epoxy resins (qv) are used in fiber-reinforced larninates, for encapsulating electronic components, and in advanced composites for aircraft—aerospace and automotive appHcations. Bisphenol A is also used for the production of corrosion- and chemical-resistant polyester resins, polysulfone resins, polyetherimide resins, and polyarylate resins. 

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