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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.
In the context of textile applications, PET is referred to by its common name, polyester, whereas the acronym PET is generally used in relation to packaging. [citation needed] Polyester makes up about 18% of world polymer production and is the fourth-most-produced polymer after polyethylene (PE), polypropylene (PP) and polyvinyl chloride (PVC).
Depending on the chemical structure, polyester can be a thermoplastic or thermoset. There are also polyester resins cured by hardeners; however, the most common polyesters are thermoplastics. [11] The OH group is reacted with an Isocyanate functional compound in a 2 component system producing coatings which may optionally be pigmented ...
Structure of polydimethylsiloxane, illustrating a polymer with an inorganic backbone. The chemist Hermann Staudinger first proposed that polymers consisted of long chains of atoms held together by covalent bonds, which he called macromolecules. His work expanded the chemical understanding of polymers and was followed by an expansion of the ...
For example, the structure of a crystalline protein or polynucleotide, such as a sample prepared for x-ray crystallography, may be defined in terms of a conventional unit cell composed of one or more polymer molecules with cell dimensions of hundreds of angstroms or more. A synthetic polymer may be loosely described as crystalline if it ...
PMMA technology is utilized in roofing and waterproofing applications. By incorporating a polyester fleece sandwiched between two layers of catalyst-activated PMMA resin, a fully reinforced liquid membrane is created in situ. PMMA is a widely used material to create deal toys and financial tombstones.
The structure of isotactic polypropylene. The structure of atactic polypropylene. Whether or not polymers can crystallize depends on their molecular structure – presence of straight chains with regularly spaced side groups facilitates crystallization. For example, crystallization occurs much easier in isotactic than in the atactic ...
Solvent impregnated resins (SIRs) are porous resin particles which contain an additional liquid extractant inside the porous matrix. The contained extractant is supposed to enhance the capacity of the resin particles. A large category of resins, which constitutes 75% of resins used, [citation needed] is that of the unsaturated polyester resins.