Polytetrahydrofuran, also called poly(tetramethylene ether) glycol or poly(tetramethylene oxide), is a
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
with formula ()
''n''OH
2 or HO-(-(CH
2)
4O-)
''n''-H. It can be viewed as a polymer of
tetrahydrofuran
Tetrahydrofuran (THF), or oxolane, is an organic compound with the formula (CH2)4O. The compound is classified as heterocyclic compound, specifically a cyclic ether. It is a colorless, water-miscible organic liquid with low viscosity. It is ma ...
, or as the
polyether
In organic chemistry, ethers are a class of compounds that contain an ether group—an oxygen atom connected to two alkyl or aryl groups. They have the general formula , where R and R′ represent the alkyl or aryl groups. Ethers can again be c ...
derived from
1,4-butanediol
1,4-Butanediol, colloquially known as BD or BDO, is a primary alcohol, and an organic compound, with the formula HOCH2CH2CH2CH2OH. It is a colorless viscous liquid. It is one of four stable isomers of butanediol.
Synthesis
In industrial sy ...
.
The product is commercially available as polymers of low average
molecular weight
A molecule is a group of two or more atoms held together by attractive forces known as chemical bonds; depending on context, the term may or may not include ions which satisfy this criterion. In quantum physics, organic chemistry, and bioch ...
s, 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
Invista (stylized as INVISTA), headquartered in Wichita, Kansas, United States, is a fiber, resin and intermediates company. It has about 10,000 employees in over 20 countries worldwide. The predecessor DuPont Textiles and Interiors was formed fro ...
and PolyTHF from
BASF
BASF Societas Europaea, SE () is a German multinational corporation, multinational chemical company and the List of largest chemical producers, largest chemical producer in the world. Its headquarters is located in Ludwigshafen, Germany.
The ...
. The BASF plant in
Ludwigshafen
Ludwigshafen, officially Ludwigshafen am Rhein (; meaning " Ludwig's Port upon Rhine"), is a city in the German state of Rhineland-Palatinate, on the river Rhine, opposite Mannheim. With Mannheim, Heidelberg, and the surrounding region, it form ...
at one point was producing 250,000 metric tons per year.
Polytetrahyrofuran polyethylene glycol can be controlled for export from the U.S. under the Export Administration Regulations on th
Commerce Control Listand/or on export control regulations based on th
Wassenaar Arrangement(ECCN: 1C111.b.5). Under these regulations export/transfer of the product may require a license or export authorization.
Applications
![Container 【 22T6 】 CCRU 164132(1) 【 Pictures taken in Japan 】](https://upload.wikimedia.org/wikipedia/commons/3/33/Container_%E3%80%90_22T6_%E3%80%91_CCRU_164132%281%29_%E3%80%90_Pictures_taken_in_Japan_%E3%80%91.jpg)
The main use of polytetrahydrofuran is to make
elastic
Elastic is a word often used to describe or identify certain types of elastomer, elastic used in garments or stretchable fabrics.
Elastic may also refer to:
Alternative name
* Rubber band, ring-shaped band of rubber used to hold objects togeth ...
fibres such as
spandex
Spandex, Lycra, or elastane is a synthetic fiber known for its exceptional elasticity. It is a polyether-polyurea copolymer that was invented in 1958 by chemist Joseph Shivers at DuPont's Benger Laboratory in Waynesboro, Virginia, US.
The ge ...
(elastane) for stretchable
fabric
Textile is an umbrella term that includes various fiber-based materials, including fibers, yarns, filaments, threads, different fabric types, etc. At first, the word "textiles" only referred to woven fabrics. However, weaving is not the ...
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
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethane is produced fro ...
made by reacting PTMEG with di
isocyanates
In organic chemistry, isocyanate is the functional group with the formula . Organic compounds that contain an isocyanate group are referred to as isocyanates. An organic compound with two isocyanate groups is known as a diisocyanate. Diisocyan ...
, or
polyester
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include natural ...
s made by reacting PTMEG with diacids or their derivatives.
The polymer is also a starting material for
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 ...
polyurethane
Polyurethane (; often abbreviated PUR and PU) refers to a class of polymers composed of organic chemistry, organic units joined by carbamate (urethane) links. In contrast to other common polymers such as polyethylene and polystyrene, polyurethan ...
, thermoplastic
polyesters
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include natural ...
,
polyetheramide and cast polyurethane elastomers, used for instance in the wheels of
roller skates
Roller skates, are shoes or bindings that fit onto shoes that are worn to enable the wearer to roll along on wheels. The first roller skate was an inline skate design, effectively an ice skate with wheels replacing the blade. Later the "quad ska ...
and
skateboard
A skateboard is a type of sports equipment used for skateboarding. They are usually made of a specially designed 7-8 ply maple plywood deck and polyurethane wheels attached to the underside by a pair of skateboarding trucks.
The skateboarde ...
s.
Synthesis
Polytetrahydrofuran is commonly prepared by acid-catalyzed
polymerization
In polymer chemistry, polymerization (American English), or polymerisation (British English), is a process of reacting monomer, monomer molecules together in a chemical reaction to form polymer chains or three-dimensional networks. There are ...
of tetrahydrofuran.
The starting material is natural gas, which is converted to
acetylene
Acetylene (systematic name: ethyne) is the chemical compound with the formula and structure . 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 its pure ...
, then reacted with
formaldehyde
Formaldehyde ( , ) (systematic name methanal) is a naturally occurring organic compound with the formula and structure . The pure compound is a pungent, colourless gas that polymerises spontaneously into paraformaldehyde (refer to section F ...
to make
butynediol and then
butanediol Butanediol, also called butylene glycol, may refer to any one of four stable structural isomers:
* 1,2-Butanediol
* 1,3-Butanediol
*1,4-Butanediol
*2,3-Butanediol
2,3-Butanediol is the organic compound with the formula (CH3CHOH)2. It is classif ...
. The latter is turned into tetrahydrofuran by action of a
catalyst
Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recyc ...
and then polymerized.
References
{{reflist
Diols
Polyethers