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Polyester resins are synthetic resins formed by the reaction of dibasic organic acids and polyhydric alcohols. Maleic anhydride is a commonly used raw material with diacid functionality in unsaturated polyester resins. [1] Unsaturated polyester resins are used in sheet moulding compound, bulk moulding compound and the toner of laser printers.
Alternately, resin casting may be accomplished with a resin plus a nearly equal amount of a "hardener" liquid (as in many epoxy resin or polyester resin systems), which functionally contains a second polymer, for use in forming a final product plastic which is a copolymer. Copolymers contain two different alternating chemical entities in the ...
Polyester fiber is used as cushioning and insulating material in pillows, comforters, stuffed animals and characters, and upholstery padding. Polyester fabrics are highly stain-resistant since polyester is a hydrophobic material, making it hard to absorb liquids.
The inclusion of a fatty acid confers a tendency to form flexible coatings. Alkyds are used in paints, varnishes and in moulds for casting. They are the dominant resin or binder in most commercial oil-based coatings. Approximately 200,000 tons of alkyd resins are produced each year. [3]
E. I. DuPont de Nemours in Delaware, United States, first produced Dacron (PET fiber) in 1950 and used the trademark Mylar (boPET film) in June 1951 and received registration of it in 1952. [27] [28] It is still the best-known name used for polyester film. The current owner of the trademark is DuPont Teijin Films.
BMC is manufactured by mixing strands (Greater than 1/8” and less than 2" [2] [3]) of chopped glass fibers, styrene, an initiator, and filler in a mixer with an unsaturated thermoset resin (commonly polyester resin, vinyl ester resin or epoxy resin). The mixing is done at room temperature and stored at low temperatures to slow down curing ...
Polymer solution casting technology can be deployed utilizing a host of different polymer materials depending on the application and design inputs, including those used in Class I, II and III medical devices, [2] and for the preparation of polymer electrolytes.
Lost wax casting can be dated back to 4000 BC or the Chalcolithic period. [4] One of the oldest studied examples of this technique is a 6,000-year-old amulet from the Indus Valley Civilisation. [9] India is attributed as one of the first civilizations to use casting methods to mass-produce coins.