Polytetrahydrofuran
Encyclopedia
Polytetrahydrofuran, also called poly(tetramethylene ether) glycol or poly(tetramethylene oxide), is a chemical compound
with formula n(OH)2 or HO-(-(CH2)4O-)n-OH. It can be viewed as a polymer of tetrahydrofuran
, or as the polyether derived from 1,4-butanediol
.
The product is commercially available as polymers of low average molecular weights, between 250 and 3000 daltons
In this form it is a white waxy solid that melts between 20 and 30 °C. The commercial product can be processed further into polymers with molecular weights of 40,000 and higher.
The product is sold under various trade names including Terathane from Invista
and PolyTHF from BASF
. The BASF plant in Ludwigshafen at one point was producing 185,000 metric tons per year.
(elastan) for stretchable fabric
s and for polyurethane resins. The latter are polyurethane prepolymers dissolved in solvent. They are used in the manufacture of artificial leather. These elastomers are either polyurethanes made by reacting PTMEG with diisocyanates, or polyesters made by reacting PTMEG with diacids or their derivatives.
The polymer is also a starting material for thermoplastic
polyurethane
, thermoplastic polyesters, polyetheramide and cast polyurethane elastomers, used for instance in the wheels of roller skates
and skateboard
s.
of tetrahydrofuran.. The starting material is natural gas, which is converted to acetylene
, then reacted with formaldehyde
to make butynediol and then butanediol
. The latter is turned into tetrahydrofuran by action of a catalyst and then polymerized.
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
with formula n(OH)2 or HO-(-(CH2)4O-)n-OH. It can be viewed as a polymer of tetrahydrofuran
Tetrahydrofuran
Tetrahydrofuran is a colorless, water-miscible organic liquid with low viscosity at standard temperature and pressure. This heterocyclic compound has the chemical formula 4O. As one of the most polar ethers with a wide liquid range, it is a useful solvent. Its main use, however, is as a precursor...
, or as the polyether derived from 1,4-butanediol
1,4-Butanediol
1,4-Butanediol is the organic compound with the formula HOCH2CH2CH2CH2OH. This colorless viscous liquid is derived from butane by placement of alcohol groups at each end of the chain. It is one of four stable isomers of butanediol.-Synthesis:...
.
The product is commercially available as polymers of low average molecular weights, between 250 and 3000 daltons
Atomic mass unit
The unified atomic mass unit or dalton is a unit that is used for indicating mass on an atomic or molecular scale. It is defined as one twelfth of the rest mass of an unbound neutral atom of carbon-12 in its nuclear and electronic ground state, and has a value of...
In this form it is a white waxy solid that melts between 20 and 30 °C. The commercial product can be processed further into polymers with molecular weights of 40,000 and higher.
The product is sold under various trade names including Terathane from Invista
INVISTA
Invista, headquartered in Wichita, Kansas, is the world's largest integrated fiber, resin and intermediates company. DuPont originally formed the company as a subsidiary in 2003 from its textile fibers division and named it DuPont Textiles and Interiors while a permanent identity was established...
and PolyTHF from BASF
BASF
BASF SE is the largest chemical company in the world and is headquartered in Germany. BASF originally stood for Badische Anilin- und Soda-Fabrik . Today, the four letters are a registered trademark and the company is listed on the Frankfurt Stock Exchange, London Stock Exchange, and Zurich Stock...
. The BASF plant in Ludwigshafen at one point was producing 185,000 metric tons per year.
Applications
The main use of polytetrahydrofuran is to make elastic fibers such as spandexSpandex
Spandex or elastane is a synthetic fibre known for its exceptional elasticity. It is strong, but less durable than natural Latex, its major non-synthetic competitor. It is a polyurethane-polyurea copolymer that was co-invented in 1959 by chemists C. L. Sandquist and Joseph Shivers at DuPont's...
(elastan) for stretchable fabric
Fabric
A fabric is a textile material, short for "textile fabric".Fabric may also refer to:*Fabric , the spatial and geometric configuration of elements within a rock*Fabric , a nightclub in London, England...
s and for polyurethane resins. The latter are polyurethane prepolymers dissolved in solvent. They are used in the manufacture of artificial leather. These elastomers are either polyurethanes made by reacting PTMEG with diisocyanates, or polyesters made by reacting PTMEG with diacids or their derivatives.
The polymer is also a starting material for thermoplastic
Thermoplastic
Thermoplastic, also known as a thermosoftening plastic, is a polymer that turns to a liquid when heated and freezes to a very glassy state when cooled sufficiently...
polyurethane
Polyurethane
A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...
, thermoplastic polyesters, polyetheramide and cast polyurethane elastomers, used for instance in the wheels of roller skates
Roller skates
Roller skates are devices worn on the feet to enable the wearer to roll along on wheels. A first basic type of roller skate consists of a boot with four wheels with ball bearings, arranged in the same configuration as the wheels of a typical car.-History:...
and skateboard
Skateboard
A skateboard is typically a specially designed plywood board combined with a polyurethane coating used for making smoother slides and stronger durability, used primarily for the activity of skateboarding. The first skateboards to reach public notice came out of the surfing craze of the early 1960s,...
s.
Synthesis
Polytetrahydrofuran is commonly prepared by acid-catalyzed polymerizationPolymerization
In polymer chemistry, polymerization is a process of reacting monomer molecules together in a chemical reaction to form three-dimensional networks or polymer chains...
of tetrahydrofuran.. The starting material is natural gas, which is converted to acetylene
Acetylene
Acetylene is the chemical compound with the formula C2H2. It is a hydrocarbon and the simplest alkyne. This colorless gas is widely used as a fuel and a chemical building block. It is unstable in pure form and thus is usually handled as a solution.As an alkyne, acetylene is unsaturated because...
, then reacted with formaldehyde
Formaldehyde
Formaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...
to make butynediol and then butanediol
Butanediol
Butanediol may refer to:*1,2-Butanediol*1,3-Butanediol*1,4-Butanediol*2,3-Butanediol...
. The latter is turned into tetrahydrofuran by action of a catalyst and then polymerized.