Early Attempts at Fluoropolymers
Following the discovery of elemental fluorine, scientists began exploring the synthesis and properties of fluorinated compounds. However, the development of practical applications for these compounds was hindered by the extreme reactivity and corrosiveness of fluorine gas. It was not until the 1930s that advancements in polymer chemistry paved the way for the synthesis of stable fluoropolymers. A team of scientists led by Dr. Roy J. Plunkett at the time was investigating the development of a new refrigerant gas. While experimenting with tetrafluoroethylene (TFE), Plunkett accidentally stumbled upon a waxy white substance instead of the anticipated gas. This serendipitous discovery in 1938 led to the identification of polytetrafluoroethylene (PTFE), the first commercially successful fluoropolymer.
Industrial Applications and Commercialization of Fluoropolymers
After its discovery, the commercial potential of PTFE became evident. Throughout the 1950s ~ 1990s, researchers studied fluoropolymer blends to explore new fluoroplastic materials. Here are some important timing nodes:
- In 1953, Kellog Co. introduced polychlorotrifluoroethylene (PCTFE), a more easily processable alternative to PTFE.
- In 1960, FEP (fluorinated ethylene propylene), the first TFE copolymer, was introduced.
- In 1961, polyvinyl fluoride (PVF) and polyvinylidene fluoride (PVDF) were successively released. PVF and PVDF have lower fluorine content, but still maintain many of the chemical and thermal properties of PTFE.
- From 1970 to 1972, ECTFE and ETFE, which are ethylene (E) copolymers of CTFE and TFE, respectively, were launched. It is the first fluoropolymer containing non-fluorinated subunits and has the hybrid properties of hydrocarbon and fluorocarbon polymers.
- In 1972, perfluoroalkoxy (PFA) copolymers obtained from TFE and perfluoropropyl vinyl ether (PPVE) were developed. PFA quickly found applications in the chemical and semiconductor industries, such as pipes, fittings, linings, and specialized films.
- In 1993, THV, a semi-crystalline three-component terpolymer of tetrafluoroethylene, hexafluoropropylene and vinylidene fluoride, came out. THVs are highly flexible, soluble in polar organic solvents, and have excellent adhesion properties, making them ideal for thin film coatings and multilayer structures.
References
- Sina Ebnesajjad. Introduction to Fluoropolymers Materials, Technology and Applications, 2013, 17-35.
- James Gardiner. Australian Journal of Chemistry, 2014, 68(1), 13-22.
