Authors:L. Olvera, E. Bucio, A. Contreras-García, G. Cedillo, C. Booth, and P. Cassidy
A series of fluoropolymer films was synthesized by reacting 1,3-bis(1,1,1,3,3,3-hexafluoro-2-pentafluorophenylmethoxy-2-propyl)benzene
(12F-FBE) with a series of bisphenol monomers via a polycondensation reaction. The biphenols used included a diphenol-substituted
spirodilactam, biphenol, bisphenol A, bisphenol AF, bisphenol F and bisphenol O. Polymers films from these new fluoropolyaryl
ethers were irradiated by a Gamma Beam 657-PT at a dose rate of 9 kGy/h; the absorbed dose was varied between 30 and 150 kGy.
The effect on the chemical structure upon radiation was studied by DSC, TGA, FTIR-ATR, NMR, and GPC, both before and after
irradiation. The data obtained allowed the determination of the degradation radiochemical yield (Gs), between 0.24 and 7.43 crosslinking radiochemical yield (Gx), from 0.03 to 1.47 and the ratio of Gs/Gx was between 2.89 and 8.28. There was no apparent physical change, from 30 to 150 kGy; the films continue to be flexible and
transparent after irradiation.
Poly(vinylidene fluoride) (PVF 2 ) based coatings are widely used as an exterior architectural coatings due to good long-term weathering and superior resistance to color fade. Conventional fluoropolymer coatings
Authors:R. Sanderson, F. du Toit, P. Carstens, and J. Wagener
Polyolefins and fluoropolymers were reacted with elemental fluorine under carefully controlled conditions in a thermobalance
adapted to be compatible with fluorine gas. The fluorination reactions were monitored by measuring the mass increase as a
result of hydrogen substitution by fluorine. The mass increase was directly proportional to the square root of the fluorination
time, which indicates that fluorine gas diffusion to the unreacted surface is the rate determining step. The fluorination
rate was increased by increasing the fluorine concentration and the fluorination temperature. The fluorination rate is higher
when nitrogen rather than helium is used as diluting gas. The fluorination rate for the reaction in which CO2 is used as diluting gas is the same as during fluorination with nitrogen as diluting gas, while the presence of oxygen dramatically
decreased the fluorination rate. Oxygen is incorporated during fluorination with oxygen as diluting gas, while no functionalization
was observed when CO2 was employed as diluting gas. The effect of polymer structure on fluorination was studied. Poly(vinylfluoride) gained mass
during fluorination, while no reaction was observed for poly(vinylidenefluoride). The reaction rate for polypropylene was
higher than that of polyethylene.
Fluoropolymers are technical polymers with very special properties and applications. The most important fluoropolymer is poly(tetrafluoroethene) (PTFE or Teflon) consist of a fluorinated straight chain polymer
Authors:Hengfeng Li, Kaiyuan Tan, Zeming Hao, and Guowen He
Lu , Y , Claude , J , Zhang , Q , Wang , Q . Microstructures and dielectric properties of the ferroelectric Fluoropolymers synthesized via reductive dechlorination of poly(vinylidene fluoride-co-chlorotrifluoroethylene)s . Macromolecules