ECTFE
Encyclopedia
ECTFE is a fluorocarbon
-based polymer
(a fluoropolymer
), a kind of plastic
. It is marketed under the brand name Halar ECTFE by Solvay Solexis. Solvay Solexis is the only producer of Halar.
resistance over a wide temperature range — typically -76°C to +150°C (-105°F to +300°F). It has high resistivity
and low dielectric constant
.
in high-friction
applications, where dimensional stability is a requirement.
Some typical applications include bearing
s, cam
s, valve seats
, semiconductor
tooling and wire
and cable
. It is used as a bearing surface
for machine tool
ways. It is also used in electrical insulators
due to its high resistivity and low dielectric constant.
ECTFE is commonly available as sheets, bars, rods and nonwoven rollgoods. It may be bonded using the same type of epoxy resin
or ultrasonics as other fluoropolymers.
ECTFE can be melt blown into a nonwoven fabric. The resultant fine fibers having the same low reactivity as Halar but important characteristics due to the high surface area
and porosity
. Such applications include filters
for highly reactive acids or alkalis even at elevated temperatures, coalescing
of oil
from water using the high surface energy
or battery
separators. Another unique application of strips of Halar web is to produce a Halar veil that can be used to construct pipes or valves for use in corrosive environments such as chloro-alkalis facilities.
In many ways the chemical properties resemble PTFE
(teflon) but with lower melting point
(and higher price)
Fluorocarbon
Fluorocarbons, sometimes referred to as perfluorocarbons or PFCs, are organofluorine compounds that contain only carbon and fluorine bonded together in strong carbon–fluorine bonds. Fluoroalkanes that contain only single bonds are more chemically and thermally stable than alkanes...
-based polymer
Polymer
A polymer is a large molecule composed of repeating structural units. These subunits are typically connected by covalent chemical bonds...
(a fluoropolymer
Fluoropolymer
A fluoropolymer is a fluorocarbon based polymer with multiple strong carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases.-History:Fluoropolymers were accidentally discovered in 1938 by Dr. Roy J...
), a kind of plastic
Plastic
A plastic material is any of a wide range of synthetic or semi-synthetic organic solids used in the manufacture of industrial products. Plastics are typically polymers of high molecular mass, and may contain other substances to improve performance and/or reduce production costs...
. It is marketed under the brand name Halar ECTFE by Solvay Solexis. Solvay Solexis is the only producer of Halar.
Physical and chemical properties
It offers high impact strength, chemical and corrosionCorrosion
Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen...
resistance over a wide temperature range — typically -76°C to +150°C (-105°F to +300°F). It has high resistivity
Resistivity
Electrical resistivity is a measure of how strongly a material opposes the flow of electric current. A low resistivity indicates a material that readily allows the movement of electric charge. The SI unit of electrical resistivity is the ohm metre...
and low dielectric constant
Dielectric constant
The relative permittivity of a material under given conditions reflects the extent to which it concentrates electrostatic lines of flux. In technical terms, it is the ratio of the amount of electrical energy stored in a material by an applied voltage, relative to that stored in a vacuum...
.
Applications
ECTFE is used to minimize wearWear
In materials science, wear is erosion or sideways displacement of material from its "derivative" and original position on a solid surface performed by the action of another surface....
in high-friction
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and/or material elements sliding against each other. There are several types of friction:...
applications, where dimensional stability is a requirement.
Some typical applications include bearing
Bearing (mechanical)
A bearing is a device to allow constrained relative motion between two or more parts, typically rotation or linear movement. Bearings may be classified broadly according to the motions they allow and according to their principle of operation as well as by the directions of applied loads they can...
s, cam
Cam
A cam is a rotating or sliding piece in a mechanical linkage used especially in transforming rotary motion into linear motion or vice-versa. It is often a part of a rotating wheel or shaft that strikes a lever at one or more points on its circular path...
s, valve seats
Valve
A valve is a device that regulates, directs or controls the flow of a fluid by opening, closing, or partially obstructing various passageways. Valves are technically pipe fittings, but are usually discussed as a separate category...
, semiconductor
Semiconductor
A semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
tooling and wire
Wire
A wire is a single, usually cylindrical, flexible strand or rod of metal. Wires are used to bear mechanical loads and to carry electricity and telecommunications signals. Wire is commonly formed by drawing the metal through a hole in a die or draw plate. Standard sizes are determined by various...
and cable
Cable
A cable is two or more wires running side by side and bonded, twisted or braided together to form a single assembly. In mechanics cables, otherwise known as wire ropes, are used for lifting, hauling and towing or conveying force through tension. In electrical engineering cables are used to carry...
. It is used as a bearing surface
Bearing surface
A bearing surface is a mechanical engineering term that refers to the area of contact between two objects. It usually is used in reference to bolted joints and bearings, but can be applied to a wide variety of engineering applications....
for machine tool
Machine tool
A machine tool is a machine, typically powered other than by human muscle , used to make manufactured parts in various ways that include cutting or certain other kinds of deformation...
ways. It is also used in electrical insulators
Electrical insulation
thumb|250px|[[Coaxial Cable]] with dielectric insulator supporting a central coreThis article refers to electrical insulation. For insulation of heat, see Thermal insulation...
due to its high resistivity and low dielectric constant.
ECTFE is commonly available as sheets, bars, rods and nonwoven rollgoods. It may be bonded using the same type of epoxy resin
Epoxy
Epoxy, also known as polyepoxide, is a thermosetting polymer formed from reaction of an epoxide "resin" with polyamine "hardener". Epoxy has a wide range of applications, including fiber-reinforced plastic materials and general purpose adhesives....
or ultrasonics as other fluoropolymers.
ECTFE can be melt blown into a nonwoven fabric. The resultant fine fibers having the same low reactivity as Halar but important characteristics due to the high surface area
Surface area
Surface area is the measure of how much exposed area a solid object has, expressed in square units. Mathematical description of the surface area is considerably more involved than the definition of arc length of a curve. For polyhedra the surface area is the sum of the areas of its faces...
and porosity
Porosity
Porosity or void fraction is a measure of the void spaces in a material, and is a fraction of the volume of voids over the total volume, between 0–1, or as a percentage between 0–100%...
. Such applications include filters
Filter (chemistry)
In chemistry and common usage, a filter is a device that is designed to physically block certain objects or substances while letting others through. Filters are often used to remove solid substances suspended in fluids, for example to remove air pollution, to make water drinkable, and to prepare...
for highly reactive acids or alkalis even at elevated temperatures, coalescing
Coalescence (chemistry)
In chemistry, coalescence is a process in which two phase domains of the same composition come together and form a larger phase domain.-References:*...
of oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
from water using the high surface energy
Surface energy
Surface energy quantifies the disruption of intermolecular bonds that occur when a surface is created. In the physics of solids, surfaces must be intrinsically less energetically favorable than the bulk of a material, otherwise there would be a driving force for surfaces to be created, removing...
or battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
separators. Another unique application of strips of Halar web is to produce a Halar veil that can be used to construct pipes or valves for use in corrosive environments such as chloro-alkalis facilities.
In many ways the chemical properties resemble PTFE
Polytetrafluoroethylene
Polytetrafluoroethylene is a synthetic fluoropolymer of tetrafluoroethylene that finds numerous applications. PTFE is most well known by the DuPont brand name Teflon....
(teflon) but with lower melting point
Melting point
The melting point of a solid 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 depends on pressure and is usually specified at standard atmospheric pressure...
(and higher price)
See also
- bs4994BS4994BS4994 is the "specification for the design and construction of vessels and storage tanks in reinforced plastics"...
ECTFE as a thermoplastic lining for dual laminate chemical process plant equipments