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Polycarbonate is mainly used for electronic applications that capitalize on its collective safety features. A good electrical insulator with heat-resistant and flame-retardant properties, it is used in products associated with power systems and telecommunications hardware. It can serve as a dielectric in high-stability capacitors. [6]
Molecular structure of Kevlar Molecular structure of the LCP Vectran [5]. Liquid crystallinity in polymers may occur either by dissolving a polymer in a solvent (lyotropic liquid-crystal polymers) or by heating a polymer above its glass or melting transition point (thermotropic liquid-crystal polymers). [6]
A polycarbonate is an oxocarbon dianion consisting of a chain of carbonate units, where successive carbonyl groups are directly linked to each other by shared additional oxygen atoms. That is, they are the conjugate bases of polycarbonic acids , the conceptual anhydrides of carbonic acid , or polymers of carbon dioxide .
It was also used as a plasticizer in paints and especially "coal tars" that were used widely to coat water tanks, bridges and other infrastructure pieces. Modern sources include pigments, which may be used in inks for paper or plastic products. [32] PCBs are also still found in old equipment like capacitors, ballasts, X-ray machine, and other e ...
The above mechanism considered crystallization from the melt, which is important for injection molding of plastic components. Another type of crystallization occurs upon extrusion used in making fibers and films. In this process, the polymer is forced through, e.g., a nozzle that creates tensile stress which partially aligns its molecules. Such ...
An example of an ionomer, with carboxylate groups bound to a zinc cation. An ionomer (/ ˌ aɪ ˈ ɑː n ə m ər /) (iono-+ -mer) is a polymer composed of repeat units of both electrically neutral repeating units and ionized units covalently bonded to the polymer backbone as pendant group moieties.
There are two main methods used to synthesize conductive polymers, chemical synthesis and electro (co)polymerization. The chemical synthesis means connecting carbon-carbon bond of monomers by placing the simple monomers under various condition, such as heating, pressing, light exposure and catalyst.
The development of plastics has evolved from the use of naturally plastic materials (e.g., gums and shellac) to the use of the chemical modification of those materials (e.g., natural rubber, cellulose, collagen, and milk proteins), and finally to completely synthetic plastics (e.g., bakelite, epoxy, and PVC).