What Is Ptfe Used For In Makeup

What is PTFE?

What is PTFE?

Polytetrafluoroethylene or PTFE is the commonly used versatile, high-operation fluoropolymer fabricated up of carbon and fluorine atoms. 1 of the common applications of this polymer is not-stick coating in kitchen cookware (pans, baking trays etc.), hence, you can hands find this in your kitchen.

Apart from being used in the kitchen, PTFE is used as a price-effective solution for industries ranging from oil & gas, chemical processing, industrial to electrical/electronic and construction sector, etc.

The basic properties of PTFE which make information technology an interesting textile with loftier commercial value are:

• Exception chemical resistance
• Adept resistance to estrus and depression temperature
• Good electric insulating power in hot and wet environments
• Good resistance to light, UV and weathering
• Low coefficient of friction
• Low dielectric constant/dissipation factor
• Stiff anti-adhesion properties
• Flexibility
• Skillful fatigue resistance nether low stress
• Availability of food, medical and high-purity grades
• Low water absorption

PTFE is a linear polymer of tetrafluoroethylene (TFE). It is manufactured by a free-radical polymerization mechanism in an aqueous media via the improver polymerization of TFE in a batch process.

The chemic structure of PTFE [CF₂-CF₂]_n is like that of polyethylene (PE), except that the hydrogen atoms are completely replaced by fluorine (hence it is referred equally perfluoro polymer). However, it is important to note that in practise PTFE and PE are prepared and used in totally unlike ways.

Molecular Structure of PTFE

It is the size of a fluorine atom which forms a uniform and continuous sheath around carbon-carbon-bonds and hence imparts skilful chemic resistance and stability to the molecule. This uniform fluorine sheath as well provides electric inertness to the molecule.

The fluorine content in PTFE is theoretically 76% and it has 95% crystallinity.

PTFE was first discovered "accidentally" in 1938 by Dr. Plunkett at DuPont. After that PTFE was made commercially available in 1947 with the trademark "Teflon™" from Chemours . Information technology was the discovery of PTFE that accelerated the development of the other fluoropolymers.

Typical Characteristics and Backdrop of PTFE

Typical Characteristics and Backdrop of PTFE

PTFE is available in granular, fine pulverisation and water-based dispersion forms.

• The granular PTFE resin is produced by suspension polymerization in an aqueous medium with piddling or no dispersing agent. Granular PTFE resins are mainly used for molding (pinch and isostatic) and ram extrusion.
• The fine PTFE powder is prepared past controlled emulsion polymerization, and the products are white, small-sized particles. Fine PTFE powders can exist processed into thin sections by paste extrusion or used equally additives to increment wear resistance or frictional property of other materials.
• PTFE dispersions are prepared past the aqueous polymerization using more dispersing agents with agitation. Dispersions are used for coatings and film casting.

As discussed above, PTFE has excellent properties such equally chemical inertness, estrus resistance (both high and low), electrical insulation backdrop, low coefficient of friction (static 0.08 and dynamic 0.01), and nonstick property over a wide temperature range (260 to 260°C) - thus making information technology suitable for a wide range of applications.

Applications of Polytetrafluoroethylene (PTFE)

• Information technology has a density in the range of 2.one - 2.3 1000/cmⁱⁱⁱ and melt viscosity in the range of 1 -10 GPa per second


• PTFE is amidst the well-nigh chemically resistant polymer. The exceptions include molten alkali metals, gaseous fluorine at high temperatures and pressures, and a few organic halogenated compounds such every bit chlorine trifluoride (ClF₃) and oxygen difluoride (OF_ii)...View PTFE Grades With Good Chemical Resistance


• Mechanical properties of PTFE are mostly junior to engineering plastics at room temperature. Compounding with fillers has been the strategy to overcome this shortage. PTFE has useful mechanical properties in its use temperature range.

  The mechanical properties of PTFE are also affected by processing variables such a preform pressure, sintering temperature, cooling rate, etc. Polymer variable such as molar mass, particle size, particle size distribution poses a meaning impact on mechanical properties.



• PTFE has excellent electrical properties such every bit high insulation resistance, low dielectric abiding. has an extremely depression dielectric constant (two.0) due to the highly symmetric structure of the macromolecules.


• PTFE exhibits high thermal stability without obvious degradation below 440 °C


• PTFE materials tin be continuously used below 260°C .


• PTFE is attacked past radiations, and degradation in the air begins at a dose of 0.02 Mrad.

These properties come from the special electronic structure of the fluorine atom, the stable carbon-fluorine covalent bonding, and the unique intramolecular and intermolecular interactions between the fluorinated polymer segments and the primary bondage.

Property	Value
Melting Temperature (°C)	317-337
Tensile Modulus (MPa)	550
Elongation at Break (%)	300-550
Dielectric strength (kV/mm)	19.7
Dielectric Constant	2.0
Dynamic Co-efficient of Friction	0.04
Surface Energy (Dynes/g)	18
Appl. Temperature (°C)	260
Refractive Index	ane.35

Limitation of PTFE

Limitation of PTFE

The conventional PTFE has some limitations in its applications, such as:

• Impossibility of using conventional molten-state processing methods and difficulty and toll of the suitable specific methods
• Sensitivity to creep and abrasion
• Significant dimensional variation around glass transition temperature (19°C)
• Difficulties of joining
• Corrosive and prone to toxic fumes
• Low radiation resistance

Affect of Fillers and Additives on PTFE Backdrop

Impact of Fillers and Additives on PTFE Properties

Mechanical properties of PTFE tin be enhanced with the addition of fillers, particularly creep and wear charge per unit. Glass fiber, bronze, steel, carbon, carbon cobweb, graphite, etc. are amidst the mutual fillers used.

Drinking glass fiber has a positive impact on the creep performance of PTFE by reducing its low and loftier temperatures. Drinking glass filled compounds perform well in oxidizing environments. Further, PTFE'due south wear characteristics are improved.

Carbon reduces pitter-patter, increases hardness and elevates the thermal conductivity of PTFE. When combined with graphite, the wearable resistance of carbon-filled compounds tin be improved further. These compounds are well suited for not-lubricated applications such as piston rings in compressor cylinders. Farther, graphite imparts excellent wear backdrop to PTFE and graphite-filled PTFE has an extremely low coefficient of friction.

Carbon fiber lowers creep, increases flex and compressive modulus and raises hardness. Unlike glass fibers, carbon fibers are inert to hydrofluoric acrid and stiff bases. Carbon fiber PTFE compounds take a lower coefficient of thermal expansion and high thermal conductivity. These parts are ideal for automotive parts in shock absorbers, water pumps etc.

Bronze-filled PTFE compounds have loftier thermal and electrical electrical conductivity which is, in turn, makes these compounds well fit for awarding where a part is subjected to load in extreme temperatures.

Other fillers which are incorporated in PTFE to produce specialty compounds include Calcium fluoride, Alumina, Mica, polymeric fillers.

In general:

• Fillers result in excellent properties of PTFE at depression and loftier temperatures.
• Fillers/additives increase the porosity of PTFE compounds and hence touch electrical properties – dielectric force decreases while dielectric abiding and dissipation factor increases
• Chemical backdrop well depend on the type of filler used. In general, the chemical properties of filled PTFE compounds are not as skilful as those of unfilled resin.
• Filler impart change in electrical and thermal conductivity of PTFE

Up to twoscore% past volume of filler can be added to the PTFE without complete loss of physical properties

The impact of fillers beneath 5% is low.

Pop Techniques Used to Process PTFE

Popular Techniques Used to Process PTFE

PTFE has a very high-melt viscosity and a high-melting temperature due to rigid polymer chain structure that makes processing difficult by the normal methods of extrusion and injection molding. Processing technologies have more similarity to those of powder metallurgy than those of traditional plastics processing.

• Sintering , pressing, ram or paste extrusion, pinch molding or isotactic molding, machining, hot stamping and extrusion of presintered powders on special machines.
• Paste extrusion in which PTFE is blended with a hydrocarbon, prior to molding a preform, is used to continuously fabricate PTFE into tubes, tapes, and wire insulation. The hydrocarbon is vaporized earlier the function is sintered
• Dispersion – metallic coatings, coatings, pulverization, impregnation, cast for thin films and cobweb spinning.
• [Operating range (-270°C) -200°C to 260°C (280°C)]

The properties of the PTFE products are strongly dependent on the processing procedure, such as polymer particle size, sintering temperature and processing pressure. Therefore, other fluoropolymers are still needed for some specific applications where PTFE is not completely suitable.

This led to a search for cook-processable fluoropolymers and the evolution of other members of the family unit.

Find Suitable Polytetrafluoroethylene (PTFE) Grade

View a broad range of polytetrafluoroethylene (PTFE) grades available in the market place today, clarify technical information of each production, get technical assistance or request samples.

Source: https://omnexus.specialchem.com/selection-guide/polytetrafluoroethylene-ptfe-fluoropolymer

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