Polycyclohexylenedimethylene terephthalate (PCT) is a
thermoplastic
A thermoplastic, or thermosoft plastic, is any plastic polymer material that becomes pliable or moldable at a certain elevated temperature and solidifies upon cooling.
Most thermoplastics have a high molecular weight. The polymer chains associate ...
polyester formed from the
polycondensation
In polymer chemistry, condensation polymers are any kind of polymers whose process of polymerization involves a condensation reaction (i.e. a small molecule, such as water or methanol, is produced as a byproduct). Condensation polymers are for ...
of
terephthalic acid and
cyclohexanedimethanol
Cyclohexanedimethanol (CHDM) is a mixture of isomeric organic compounds with formula C6H10(CH2OH)2. It is a colorless low-melting solid used in the production of polyester resins. Commercial samples consist of a mixture of cis and trans isomers. ...
.
[{{cite encyclopedia, authors=Horst Köpnick, Manfred Schmidt, Wilhelm Brügging, Jörn Rüter, Walter Kaminsky, title=Polyesters, encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry, year=2002, publisher=Wiley-VCH, place=Weinheim, doi=10.1002/14356007.a21_227, isbn=3527306730] Its chemical structure is similar to that of
polyethylene terephthalate (PET), with which it shares properties like dimensional stability and chemical resistance. PCT is also particularly resistant to high temperatures and
hydrolysis
Hydrolysis (; ) is any chemical reaction in which a molecule of water breaks one or more chemical bonds. The term is used broadly for substitution, elimination, and solvation reactions in which water is the nucleophile.
Biological hydrolys ...
. The
melting point
The melting point (or, rarely, liquefaction point) of a substance is the temperature at which it changes state from solid to liquid. At the melting point the solid and liquid phase exist in equilibrium. The melting point of a substance depen ...
is 545 °F (285 °C). Common brand names are ''Thermx'' (
Ticona
Celanese Corporation, formerly known as Hoechst Celanese, is an American technology and specialty materials company headquartered in Irving, Texas. A Fortune 500 corporation, the company is the world’s leading producer of acetic acid, produc ...
), ''Eastar'' (
Eastman) and ''SkyPURA'' (
SK Chemicals
SK Group (Korean: SK그룹, 에스케이그룹) is the second largest South Korean chaebol behind Samsung Group. SK Group is composed of 186 subsidiaries and affiliates that share the SK brand name and the group's management culture, named SKMS ...
).
Application
Polycyclohexylenedimethylene terephthalate has good dimensional stability at excess temperatures (short-term up to 493 °F (256 °C)) making this material suitable for
injection molding or
3D printing
3D printing or additive manufacturing is the construction of a three-dimensional object from a CAD model or a digital 3D model. It can be done in a variety of processes in which material is deposited, joined or solidified under computer co ...
of thin-walled parts. PCT is used for electronics components like plug connectors. PCT is also processed into filaments, fibers, and fabrics that are used in industry as filters. The color stability and lower density are of advantage in other applications, especially in the LED reflector application.
References
External links
PCT using the example of Thermx(PDF)
Polycyclohexylenedimethylene terephthalate (PCT) on MatWeb
Polyesters
Thermoplastics
Terephthalate esters