Epoxy Polyesters

Epoxy-based thermosets are the most widely used and versatile thermosets. They dominated the reinforcing piping field until the introduction of the vinyl esters, and they are still widely used. They find usage in many applications, including adhesives, coatings, encapsulants, tooling compounds, composites, and molding compounds. Their versatility is due to the wide latitude in properties that can be achieved by formulation. 

A large variety of epoxy resins, modifiers, and curing agents are available that permit the epoxy formulator to tailor the epoxy system to meet the needs of each application. 

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Eig. 3. Gloss retention ia outdoor exposure ia Florida for A, epoxyresia B, epoxy—polyester hybrid resia C, browa and D, white powder coatings. White... 

Epoxy—polyester hybrids are margiaally better than straight epoxies ia gloss reteatioa oa exterior exposure (Eig. 3) but are aot recommeaded for exterior appHcatioas ia most cases. Eor the most part, appHcatioas for the hybrids are the same as those for decorative epoxies. These latter are gradually being replaced by the hybrids, which are gaining ia market share ia the Uoited States. Ia Europe, hybrids are the most widely used powder coatiag type. 

To improve the weatherabUity of epoxies, which normally chalk and yeUow, epoxy—polyester aUoys or hybrids are used. These powders with improved overbake resistance cure at temperatures as low as 130°C. They have film flexibiHty similar to epoxy resins, but their hardness is slightly decreased. Corrosion resistance is equivalent to epoxy powders in most cases, although solvent and alkaH resistance is inferior. 

The demands on insulating materials in soil and fresh water are relatively low. Anodically evolved oxygen makes the use of aging-resistant insulating materials necessary. These consist of special types of rubber (neoprene) and stabilized plastics of polyethylene, and polyvinylchloride, as well as cast resins such as acrylate, epoxy, polyester resin and many others. 

Self-leveling epoxy, polyester or reactive acrylic resin systems 9/105... 

Epoxy, polyester, phenolic and other resins are used as coatings and linings with or without reinforcement. Glass fiber, silica, carbon and many other materials can be used as filters or reinforcement to produce materials with specific properties of strength, flexibility, wear resistance and electrical conductivity. 

For this use, the preferred powders are based on acrylic, epoxy or polyester and epoxy resins. For best colour, epoxy resins are crosslinked with anhydrides of dicarboxylic acids in the straight epoxy coatings, or with saturated polyesters of high acid content in the epoxy-polyester type. Acrylics contain epoxide rings via, for example, glycidyl methacrylate (CH2=C(CH3) —CO—O—CHj—CH —CH2), and these groups crosslink... 

Two-piece food cans may be made by a draw-redraw process, in which lacquer is first applied to and cured on sheet. Blanks are then cut from the sheet and the can is drawn from the blank in two or three stages. The lacquer deforms with the drawing process and lubricates the draw. It then becomes the interior protective coating. Although epoxy-phenolic solvent-borne lacquers are used, even better drawing properties are obtained from organosols. These are dispersions of colloidal polyvinyl chloride powder in solutions of other mixed resins in solvent, e.g. chosen from epoxy, polyester, vinyl and phenolic. 

Materials. The single films and multilayered materials examined are listed in Tables I and II, respectively. The adhesive (10thick) between any two layers was a two-component curing, epoxy—polyester adhesive, Adcote 503A, Morton Chemical Co. Pouches (11.5 X 17.8 cm) were made from the multilayered materials by heat sealing the sides and bottom under the optimum heat sealing conditions (3). 

Protective coatings and lacquers may be applied as a roller or spray coating, usually based on vinyl, epoxy, polyester, phenol-alkyd resin, or wax coatings. 

Glass fibres dominate this field either as long continuous fibres (several centimetres long), which are hand-laid with the thermoset precursors, e.g., phenolics, epoxy, polyester, styrenics, and finally cured (often called fibre glass reinforcement plastic or polymer (FRP)). With thermoplastic polymers, e.g., PP, short fibres (less than 1 mm) are used. During processing with an extruder, these short fibres orient in the extrusion/draw direction giving anisotropic behaviour (properties perpendicular to the fibre direction are weaker). 

Epoxy-p-menthane, 24 528 Epoxy—polyester automotive coatings, 10 447, 449... 

Adhesives are so numerous and versatile that it is difficult to generalize by chemical type. One breakdown of synthetic adhesives by polymer type gives phenolics (37%), urea and melamine (19%), vinyls (18%), synthetic elastomers (15%), acrylics (4%), polyurethanes (3%), and epoxies, polyesters, and others (4%). For purposes of organization we divide them... 

Finally, metal- and resin-bonded composites are also classified as particulate composites. Metal-bonded composites included structural parts, electrical contact materials, metal-cutting tools, and magnet materials and are formed by incorporating metallic or ceramic particulates such as WC, TiC, W, or Mo in metal matrixes through traditional powder metallurgical or casting techniques. Resin-bonded composites are composed of particulate fillers such as silica flour, wood flour, mica, or glass spheres in phenol-formaldehyde (Bakelite), epoxy, polyester, or thermoplastic matrixes. 

Commonly used materials are gypsum board with epoxy, polyester coating, and seamless PVC coating. 

Fiber reinforced plastics (FRP) are widely utilized now for a number of cryogenic applications. The matrices used are generally thermosetting resins such as epoxies, polyesters and phenolics, since they are easy to apply in impregnating processes. 

Most of the radiation curable raw material technology is based on acrylic or methacrylic acid deritive but may also include modified epoxies, polyesters, and polyurethanes. Thus the backbones of radiation curing and conventional coatings are similar. 

There are RIM systems based on chemistry unrelated to polyurethanes that are not in significant commercial production compared to the polyurethanes. Development work has taken place with materials such as nylon. The nylon RIM material is based on caprolactam. Nylon RIM polymers offer high toughness and abrasion resistance. Polydicyclo-pentadiene is a proprietary thermoset polymer developed by Hercules. PCPD offers high-impact resistance and stiffness. It is used in the production of snowmobile components. Other polymers are used such as epoxies, polyesters, acrylics, phenolics, and styrenics. 

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