Perfluorobutyl ether

Ethyl pentyl carbinol. See 3-Octanol Ethyl pentyl ketone. See 3-Octanone Ethyl perfluorobutyl ether. See Ethyl nonafluorobutyl ether Ethyl perfluoroisobutyl ether. See Ethyl nonafluoroisobutyl ether... 

Methyl tert-pentyl ether see Methyl 1,1-dimethylpropyl ether Methyl pentyl ketone see Heptan-2-one Methyl perfluorobutyl ether see Methyl nonafluorobutyl ether Methyl phenethyl ketone see 4-Phenylbutan-2-one 3-Metfaylphenol syn. 3-Cresol Methyl phenyl ether... 

For the addition of ethylene, EtOAc as solvent was particularly advantageous and gave 418 in 60% yield (Scheme 6.86). The monosubstituted ethylenes 1-hexene, vinylcyclohexane, allyltrimethylsilane, allyl alcohol, ethyl vinyl ether, vinyl acetate and N-vinyl-2-pyrrolidone furnished [2 + 2]-cycloadducts of the type 419 in yields of 54—100%. Mixtures of [2 + 2]-cycloadducts of the types 419 and 420 were formed with vinylcyclopropane, styrene and derivatives substituted at the phenyl group, acrylonitrile, methyl acrylate and phenyl vinyl thioether (yields of 56-76%), in which the diastereomers 419 predominated up to a ratio of 2.5 1 except in the case of the styrenes, where this ratio was 1 1. The Hammett p value for the addition of the styrenes to 417 turned out to be -0.54, suggesting that there is little charge separation in the transition state [155]. In the case of 6, the p value was determined as +0.79 (see Section 6.3.1) and indicates a slight polarization in the opposite direction. This astounding variety of substrates for 417 is contrasted by only a few monosubstituted ethylenes whose addition products with 417 could not be observed or were formed in only small amounts phenyl vinyl ether, vinyl bromide, (perfluorobutyl)-ethylene, phenyl vinyl sulfoxide and sulfone, methyl vinyl ketone and the vinylpyri-dines. 

Commercial products based on copolymers of ethylene and TEE are made by free radical-initiated addition copolymerization.69 Small amounts (1 to 10 mol%) of modifying comonomers are added to eliminate a rapid embrittlement of the product at exposure to elevated temperatures. Examples of the modifying comonomers are perfluorobutyl ethylene, hexafluoropropylene, perfluorovinyl ether, and hexafluoro-isobutylene.70 ETFE copolymers are basically alternating copolymers,70 and in the molecular formula, they are isomeric with polyvinylidene fluoride (PVDF) with a head-to-head, tail-to-tail structure. However, in many important physical properties, the modified ETFE copolymers are superior to PVDF with the exception of the latter s remarkable piezoelectric and pyroelectric characteristics. 

In this entry, fluoropolymer means a polymer that consists of partially or fully fluorinated olefinic monomers, such as vinylidene fluoride (CH2=CF2) and tetrafluor-oethylene (CF2=CF2). Commercial fluoropolymers include homopolymers and copolymers. Homopolymers contain 99wt.% or more one monomer and lwt.% or less of another monomer according to the convention by American Society for Testing Materials. Copolymers contain 1 wt.% or more of one or more comonomers. The major commercial fluoropolymers are based on tetrafluoroethylene, vinylidene fluoride, and to a lesser extent chlorotrifluoroethylene. Examples of comonomers include perfluoromethyl vinyl ether (PMVE), perfluoroethyl vinyl ether (PEVE), perfluoro-propyl vinyl ether (PPVE), hexafluoropropylene (HFP), chlorotrifluoroethylene (CTFE), and perfluorobutyl ethylene (PFBE). 

The high solubility of many gases, including oxygen, in fluorocarbons has led to these compounds being used as blood substitutes in cardiopulmonary machines and as potential carriers in liquid breathing. Tham et have recently measured the solubility of O2, N2, and CO2 in the three commercially available fluoro-ethers perfluoro-l,4-di-isopropoxybutane, perfluoro-1-isopropoxyhexane, and perfluorobutyl-perfluorotetrahydrofuran and noted... 

The solvent effect in Mn2(CO)io polymerizations was explored with over 40 solvents [51] and perfluorobutyl iodide (PFBI), easily activated by Mn(CO)5 (vide infra) was used as initiator. The comparisons were made under the same conditions (VDF/PFBI/Mn2(CO)io = 25/1/0.2 VDF/solvent = 1/3 wt/v) and revealed that in accordance with the principles outlined above, no polymerization occurred in anisole, a,a,a-trifluorotoluene, diglyme, diethylene glycol monoethyl ether, ethyl ether, THF, dioxane, o-cresol, isopropanol, trifluoroacetic anhydride, tetramethylurea, sulfolane, benzonitrile, cyclopentanone even after 1-3 days. Poor reaction rates (/ p PP < 1 - 9 X 10 h ) were observed in HMPA, 2-butanone, methyl pentanone, DMF, DMSO, PEO, DMAc, 5-valerolactone, BuOH, and EtOAc. Slightly faster polymerizations (/ p PP = 1 - 1.7 X 10 h ) were seen in CH2CI2, acetic anhydride, y-butyrolactone, 1,2-dichloroethane, TMP, MeOH, pentafluorobutane, and HFBz,... 

Commercial fluoropolymers are based on TFE, vinylidene fluoride, and, to a lesser extent, CTFE. Examples of other comonomers include perfluoro-methyl vinyl ether, perfluoroethyl vinyl ether, PPVE, HFP, CTFE, and perfluorobutyl ethylene. The general consequences of the substitution of fluorine for hydrogen in a polymer include increased chemical and solvent resistance, enhanced electrical properties such as lower dielectric constant, lower coefficient of friction, higher melting point, increased photostability and thermal stability, improved flame resistance and weakened mechanical properties. The ultimate, most useful and sought-after properties are achieved in perfluorinated polymers. 

In this chapter, synthesis and properties of major monomers for polymerization of melt-processible fluo-roplastics are discussed. Tetrafluoroethylene is the primary monomer. Small amounts of other monomers are incorporated in the TFE polymer structure to modify its properties and processing characteristics. These monomers include hexafluoropropylene (HFP), per-fluoroalkylvinylethers (PAVE), and chlorotrifluoro-ethylene (CTFE). A number of specialty monomers, though less common, are also used to modify the PTFE structure. Examples include perfluoroisopropyl vinyl ether and perfluorobutyl ethylene. Preparation of important monomers including vinyl fluoride and vinylidene fluoride are reviewed. 

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