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Oligomerization anionic

Perfluoropolyethers with the linear perfluoropropoxy repeat unit have been commercialized (28). They are prepared by the anionic oligomerization of tetrafluorooxetane followed by direct fluorination to remove the acyl fluoride end group as well as to fluorinate the remaining CH2 groups n can vary widely. [Pg.298]

Hexafluoro-2-butyne readily undergoes anionic oligomerization in the presence of fluoride ion 24 ], but the intermediate vinylic carbamon can be trapped by highly electrophilic fluormated heterocycles [249] (equation 52)... [Pg.81]

The various kinds of growing species differ not only in their propagation but also in their stereochemical preferences. Professor Hogen-Esch will review this subject in his talk on anionic oligomerization of some vinyl monomer, and mechanisms of anionic, stereospecific polymerization of 2-vinyl pyridine will be discussed by Dr. Fontanille. In this context, the interesting paper of Schuerch et al.(12) deserves attention. Their work clearly reveals the effect of cation solvation upon the mode of monomer s approach to the growing centers. [Pg.5]

Ion Pair Structure and Stereochemistry in Anionic Oligomerization and Polymerization of Some Vinyl Monomers... [Pg.231]

We have recently (2,2) reported the stereoregular anionic oligomerization of 2-vinyTpyridine and various alkyl acrylates in THF and similar low dielectric constant media (Eq. 1) ... [Pg.231]

Anionic initiator, PMMA H spectra, 4 Anionic oligomerization, styrene, 182... [Pg.270]

Hall [61] as far back as 1937 first proposed intercellular diffusion. It has recently been clearly demonstrated by Feeder et al. [62] for metal complex dyes. Feeder has shown that a large cationic dye, rhodamine B (479Da) triphenyl pyrazine, a neutral molecule (311 Da) and the high-molecular-weight anionic oligomeric Synthappret BAP (>3,000Da) all penetrate hair through the intercellular route. [Pg.231]

There are also examples where the non-cross-linked polymeric reagent is most readily available by direct polymerization of suitably functionalized monomers. For example, polymerization of a crown ether which contains styrene units is possible by free radical or anionic methods (15). In the case of anionic oligomerization (Equation 6) or in the case of the metalation shown in Equation 4, the reactive intermediate macromolecule is a nucleophilic polymer which can be derivatized with a variety of electro-... [Pg.20]

Anionic Oligomerization of chloral with lithium f-butoxide (5,6)... [Pg.368]

ION PAIR EFFECTS ON THE ANIONIC OLIGOMERIZATION STEREOCHEMISTRY OF VINYL PYRIDINES AND RELATED MONOMERS... [Pg.191]

These studies demonstrate that the geometry of the carbanion site can be an important factor in the methylene stereochemistry of anionic oligomerizations and polymerizations of vinyl monomers. [Pg.1054]

Anionic fluorinated surfactants containing an oligo(hexafluoropropene oxide) chain have been prepared by anionic oligomerization of hexafluoropropene oxide (HFPO) [98,99] and hydrolysis of the oligomer, an acid fluoride [100] ... [Pg.43]

Anionic oligomerization with slow chain initiation or transfer Oligo-styrene and other vinyl oligomers 10" - 10 ... [Pg.51]

See other pages where Oligomerization anionic is mentioned: [Pg.70]    [Pg.23]    [Pg.371]    [Pg.125]    [Pg.1585]    [Pg.1585]    [Pg.14]    [Pg.182]    [Pg.37]    [Pg.39]    [Pg.4]    [Pg.75]    [Pg.331]    [Pg.302]    [Pg.9]    [Pg.145]    [Pg.204]    [Pg.211]    [Pg.182]    [Pg.1054]    [Pg.1054]    [Pg.1061]    [Pg.51]   
See also in sourсe #XX -- [ Pg.4 ]



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