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Abstract  

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 (G s), between 0.24 and 7.43 crosslinking radiochemical yield (G x), from 0.03 to 1.47 and the ratio of G s/G x 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.

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Introduction 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

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Abstract  

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.

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Introduction 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

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. Fluoropolymers Applications in Chemical Processing Industries: The Definitive User’s Guide and Databook ; William Andrew Publishing : Norwich, NY , 2004 ; (c) Tubing . IDEX Health & Science : 2014

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. 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

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. Seiler , DA 1997 PVDF in the chemical process industry J Scheirs eds. Modern fluoropolymers Wiley Chichester 487 – 505 . 3

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