Trichloroacetyl peroxide

One aspect of both EPR and CIDNP studies that should be kept in mind is that either is capable of detecting very small amounts of radical intermediates. This sensitivity makes both techniques quite useful, but it can also present a pitfall. The most prominent features of either EPR or CIDNP spectra may actually be due to radicals that account for only minor amounts of the total reaction process. An example of this was found in a study of the decomposition of trichloroacetyl peroxide in alkenes. 

Bis(fluoroformyl) peroxide, 0625 Bis-3-(2-furyl)acryloyl peroxide, 3640 Bis(trichloroacetyl) peroxide, 1361 Bis(trifluoroacetyl) peroxide, 1367 Diacetyl peroxide, 1537 Dibenzenesulfonyl peroxide, 3499 Dibenzoyl peroxide, 3639 Di-3-camphoroyl peroxide, 3807 Dicrotonoyl peroxide, 2986 Dicyclohexylcarbonyl peroxide, 3667 Didodecanoyl peroxide, 3857 Di-2-furoyl peroxide, 3245 Dihexanoyl peroxide, 3554 Diisobutyryl peroxide, 3032 Diisopropyl peroxydicarbonate, 3034 Dimethanesulfonyl peroxide, 0931 Di-2-methylbutyryl peroxide, 3354 Di-l-naphthoyl peroxide, 3831 3,6-Dioxo-l,2-dioxane, 1445 Dipropionyl peroxide, 2442 Dipropyl peroxydicarbonate, 3035 Di-4-toluenesulfonyl peroxide, 3656 Peroxodisulfuryl difluoride, 4328 Phthaloyl peroxide, 2900 Potassium benzenesulfonylperoxosulfate, 2257 Potassium O-O-benzoylmonoperoxosulfate, 2684 (9-TriIIuoroacctyl-.S -lluorofonny 1 thioperoxide, 1050 See PEROXIDES, PEROXYCARBONATE ESTERS... 

Bis(l,2,3,4-thiatriazol-5-ylthio)maleimide, 2066 Bis( 1,2,3,4-thiatriazol-5-ylthio)methane, 1081 Bis(trichloroacetyl) peroxide, 1357a Bis(2,4,5-trichlorobenzenediazo) oxide, 3425... 

Acetyl cyclohexanesulfonyl peroxide, 3028 2,2 -Biphenyldicarbonyl peroxide, 3624 Bis(2,4-dichlorobenzoyl) peroxide, 3617 Bis(2-azidobenzoyl) peroxide, 3621 Bis(3,4-dichlorobenzenesulfonyl) peroxide, 3439 Bis-3-(2-furyl)acryloyl peroxide, 3633 Bis(3-carboxypropionyl) peroxide, 2985 Bis(4-chlorobenzenesulfonyl) peroxide, 3452 Bis(bromobenzenesulfonyl) peroxide, 3447 Bis(fluoroformyl) peroxide, 0621 Bis(trichloroacetyl) peroxide, 1357 Bis(trifluoroacetyl) peroxide, 1363 Di-1-naphthoyl peroxide, 3825 Di-2-furoyl peroxide, 3239 Di-2-methylbutyryl peroxide, 3348 Di-3-camphoroyl peroxide, 3801 Di-4-toluenesulfonyl peroxide, 3649 Diacetyl peroxide, 1532 Dibenzenesulfonyl peroxide, 3493 Dibenzoyl peroxide, 3632 Dicrotonoyl peroxide, 2981 Dicyclohexylcarbonyl peroxide, 3660 Didodecanoyl peroxide, 3851 Dihexanoyl peroxide, 3548 Diisobutyryl peroxide, 3027 Diisopropyl peroxydicarbonate, 3029 Dimethanesulfonyl peroxide, 0927 3,6-Dioxo-l,2-dioxane, 1441... 

Copolymers of vinyl fluoride with such monomers as vinylidene fluoride or l-chloro-2-fluoroethylene were prepared in the presence of trichloroacetyl peroxide at 0 C in sealed tubes. The chlorine-containing copolymers were then reductively dechlorinated at 60 C in tetrahydrofuran with tri- -butyltin hydride in the presence of 2,2 -azobis(isobutyronitrile) for up to 40 hr. This general procedure led to the formation of polymers with a reasonable control of the level of head-to-head, tail-to-tail linkages in the product [27]. 

Poly(trifluorochloroethylene) was developed as a competitor to poly-(tetrafluoroethylene). The monomer synthesis proceeds from hexachloro-ethane via 1, l,2-trifluoro-l,2,2-trichloroethane. The monomer is free radically suspension polymerized with the redox system K2S20s/NaHS03/AgN03 or bulk polymerized with bis(trichloroacetyl peroxide). 

The formation of some structure units in head-to-head or tail-to-tail position is an unavoidable phenomenon of the radical polymerization of vinyl monomers. In the ease of poly(vinylidene fluoride) these chain defects are of particular importance because they affect the crystallization and thus the properties of the polymer [521]. In general, the percentage of monomer inversion in PVF2 appears to be a function of the temperature of polymerization The number of H H and T-T units increase from 3.5% at 20 °C to 6.0% at 140 °C. A polymer with a very low content of chain defects has been prepared by Butler et al. [579]. The authors carried out the polymerization in bulk at 0 °C using trichloroacetyl peroxide as the initiator and obtained high-molar-mass PVF2 with only 2.85% of reversed monomer units and low content of branches. 

Apart from the fluoro monomers vinyl fluoride (VF), vinylidene fluoride (VF2), and tetrafluoroethylene (TFE), only chlorofluoroethylene has found commercial use as homopolymer. It is applied as thermoplastic resin based on its vapor-barrier properties, superior thermal stability (Tdec > 350 °C), and resistance to strong oxidizing agents [601]. Chlorofluoroethylene is homo- and copolymerized by free-radical-initiated polymerization in bulk [602], suspension, or aqueous emulsion using organic and water-soluble initiators [603,604] or ionizing radiation [605], and in solution [606]. For bulk polymerization, trichloroacetyl peroxide [607] and other fluorochloro peroxides [608,609] have been used as initiators. Redox initiator systems are described for the aqueous suspension polymerization [603,604]. The emulsion polymerization needs fluorocarbon and chlorofluorocarbon emulsifiers [610]. 

In the work conducted by Chandrasekaran, " initiators for solvent-based polymerization included aliphatic and aromatic peroxy compounds, including fluorine and chlorine substituted organic peroxides. Specific examples are acetyl peroxide, succinic acid peroxide, 2,4-dichlorobenzoyl peroxide, t-butylper-oxypivalate, decanoyl peroxide, trichloroacetyl peroxide, and perfluoropropionyl peroxide. Aqueous polymerization was conducted using persulfate, perphosphate and perborate salts of sodium, potassium. 

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