Fluoropolymer

A fluoropolymer is a fluorocarbon-based polymer with multiple carbon–fluorine bonds. It is characterized by a high resistance to solvents, acids, and bases. The best known fluoropolymer is polytetrafluoroethylene under the brand name "Teflon," trademarked by the DuPont Company.

History

In 1938, polytetrafluoroethylene (DuPont brand name Teflon) was discovered by accident by a recently hired DuPont Ph.D., Roy J. Plunkett. While working with tetrafluoroethylene gas to develop refrigerants, he noticed that a previously pressurized cylinder had no pressure remaining. In dissecting the cylinder, he found a mass of white solid in a quantity similar to that of the tetrafluoroethylene gas. It was determined that this material was a new-to-the-world polymer. Tests showed the substance was resistant to corrosion from most acids, bases and solvents and had better high temperature stability than any other plastic. By early 1941, a crash program was making substantial quantities of PTFE for the Manhattan Project.^[1][2][3][4]

Properties

Fluoropolymers share the properties of fluorocarbons in that they are not as susceptible to the van der Waals force as hydrocarbons. This contributes to their non-stick and friction reducing properties. Also, they are stable due to the stability multiple carbon–fluorine bonds add to a chemical compound. Fluoropolymers may be mechanically characterized as thermosets or thermoplastics. Fluoropolymers can be homopolymers or Copolymer. ^{[citation needed]}

Examples of monomers used to prepare fluoropolymers

• Perfluorocycloalkene (PFCA)
• Ethylene (Ethene, E)
• Vinyl fluoride (fluoroethylene) (VF1)
• Vinylidene fluoride (1,1-difluoroethylene) (VDF or VF2)
• Tetrafluoroethylene (TFE)
• Chlorotrifluoroethylene (CTFE)
• Propylene (Propene, P)
• Hexafluoropropylene (HFP)
• Perfluoropropylvinylether (PPVE)
• Perfluoro(methyl vinyl ether) (PMVE)

Examples of fluoropolymers

Fluoropolymer	Trade names	Monomers	Melting point (°C)
PVF (polyvinylfluoride)	Tedlar[5]	VF1	200[6]
PVDF (polyvinylidene fluoride)	Kynar[7] Solef[8] Hylar[9]	VF2	175
PTFE (polytetrafluoroethylene)	Sold by AGC under the tradename Fluon PTFE; Sold by Dupont and Chemours Company under the tradename Teflon; sold by Solvay Specialty Polymers under the tradenames Algoflon Hyflon and Polymist; sold by Daikin under the tradename Polyflon	TFE	327
PCTFE (polychlorotrifluoroethylene)	Kel-F (3M), Neoflon (Daikin), Voltalef [10] (Arkema)	CTFE	220[6]
PFA, MFA[11] (perfluoroalkoxy polymer)	Sold by AGC under the tradename Fluon PFA. Sold by DuPont under the tradename Teflon-PFA. Sold by Solvay Specialty Polymers under the tradename Hyflon.[12] Neoflon (Daikin)	PPVE + TFE	305
FEP (fluorinated ethylene-propylene)	Sold by DuPont under the tradename Teflon FEP. Also known as Neoflon (Daikin) and Hyflon	HFP + TFE	260
ETFE (polyethylenetetrafluoroethylene)	Sold by AGC under the trade name of FluonETFE[13] Tefzel,;[14] sold by Daikin under the tradename Neoflon	TFE + E	265
ECTFE (polyethylenechlorotrifluoroethylene)	Halar[15] sold by Solvay Specialty Polymers	CTFE + E
FFPM/FFKM (Perfluorinated Elastomer [Perfluoroelastomer])	Kalrez.[16] Tecnoflon PFR[17] DAI-EL (Daikin)
FPM/FKM (Fluoroelastomer [Vinylidene Fluoride based copolymers])	Viton,[18] Tecnoflon FKM, DAI-EL (Daikin), Fluonox (Gujarat Fluorochemicals Limited)
FEPM (Fluoroelastomer [Tetrafluoroethylene-Propylene])	Sold by AGC under the trade name of AFLAS,[19]	TFE + P
PFPE (Perfluoropolyether)	Sold by DuPont under the tradename Krytox.[20] Sold by Solvay Specialty Polymers S.p.A. as Fomblin and Galden
PFSA (Perfluorosulfonic acid)	Nafion
Perfluoropolyoxetane

Typical properties

^[21]

Property	Method No.	Units	PTFE	FEP	PFA	ETFE	ECTFE	PCTFE	PVDF
Specific gravity	D792	-	2.17	2.15	2.15	1.7	1.7	2.15	1.78
Yield strength	D638	MPa	10	12	15.5	24	31	40	46
Yield strength	D638	PSI	1,450	1,740	2,250	3,480	4,500	5,800	6,670
Elongation		%	200-500	250-350	300	200-500	200-300	80-250	20-150
Tensile modulus	D638	MPa	600	500	700	1500	1655	1500	2400
Tensile modulus	D638	ksi	87	72.5	101.5	217.5	240	218	348
Hardness	D2240	Shore D	60	57	62	75	75	90	79
HDT, @ 66 PSI	D648	°F	250	158	164	219	240	248	300
HDT, @ 264 PSI	D648	°F	122	129	118	160	169	-	239
Limiting oxygen index	D2863	%	>95	>95	>95	30-36
Dielectric constant	D150	1 MHz	2.1	2.1	2.1	2.6

See also

• Organofluorine
• Organohalogen
• Fluorosurfactant
• Perfluorocycloalkene (PFCA)
• Per- and polyfluoroalkyl substances (PFAS)