Peroxy dicarbonates

Figure 14.3.3 The molecular structure of di-(4-tert-butylcyclohexyl)peroxy-dicarbonate, an initiator in a free-radical polymerization reaction.

The autoxidation of cyclohexane initiated by dicyclohexyl peroxy-dicarbonate (DCPD) takes this pathway 38> ... 

Synonyms potassium peroxydicarbonate potassium perdicarbonate peroxy-dicarbonic acid dipotassium salt. 

In the multiple-feed process an initiator mix is used to obtain a smooth temperature profile and low initiator consumption. The initiator mix consists of three or four organic peroxides from Table 5.1-2 differing in activity. To cover the range of lower temperatures, dicyclohexyl peroxy dicarbonate, /-butylperoxy neodecanoate, or /-butylperoxy pivalate are used. The peroxide for moderately high temperatures is frequently /-butylperoxy 2-ethylhexanoate or /-butylperoxy benzoate. The high-temperature initiator in the mix is di(/-butyl)peroxide. 

The costs assume the production of pellets on 1997 German prices. Polymerization-grade ethylene is available at 5 MPa. The on-stream time is 8,000 h/a. The tubular reactors equipped with multiple feeds of ethylene and peroxide initiators are operated at 200 MPa. The initiators are a mix of dicyclohexyl peroxy dicarbonate, /-butylperoxy pivalate, /-butylperoxy 2-ethylhexanoate, and di(/-butyl)peroxide, which is fed in after the heating zone and at two further locations downstream. 

Of the 3 possible types of peroxycarbonate esters —dialkyl monoperoxycarbon-ates, dialkyl diperoxycarbonates and dialkyl peroxydicarbonates—, the latter are by far the least stable group. Several of the 16 alkyl and substituted-alkyl esters prepared decomposed violently or explosively at temperatures only slightly above the temperature of preparation (0—10°C), owing to self-accelerating exothermic decomposition. Several were also explosive on exposure to heat, friction or shock [1]. Amines and certain metals cause accelerated decomposition of dialkyl peroxy dicarbonates by a true catalytic mechanism [2]. Individually indexed compounds are ... 

Figure 13.5 Reaction profile of a fast polymerization batch dotted line di-2-ethylhexyl peroxy dicarbonate (OPD) solid line OPD + cumyl peroxy neodecanate (after Saeki et al. [1])...

Diisopropyl peroxydicarbonate See Diisopropyl peroxy dicarbonate Amines, etc. 

Dideuterodiazomethane, 0336 Didodecanoyl peroxide, 3857 Didodecyl peroxy dicarbonate, 3865... 

Although this reaction appears to be a clear-cut example of a SET reaction, several presumptions are necessary. First the bimolecular reaction to form hydrogen peroxide is assumed to be faster than reaction of HO- with either COs -or with TEMPO radical (the latter is produced with HO- in the solvent cage). Second, formation of HOOH is assumed to be solely via HO- coupling (it also can be formed from secondary reactions e.g., from peroxy dicarbonates). ... 

Dialkyi peroxy-dicarbonates CH3 0 0 CH3 1 II II 1 H-C-O-C-O-O-C-O-C-H 1 1 C2H5 C2H5 Di-sec-butylperoxydicarbonate 45... 

Beilstein Handbook Reference) Bisisopropyl peroxydicarbonate BRN 1786996 Diisopropyl perdicarbonate Diisopropyl peroxy-dicarbonate Diisopropyl peroxydiformale EINECS 203-317-4 HSDB 349 Isopropyl percarbonate Isopropyl peroxydicarbonate Luperox IPP Peroxydicarbonate d isopropyle Petoxydicarbonic acid, bis(l-methylethyl) ester Peroxydicarbonic acid, diisopropyl ester. 

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