Propene oxide, polymerization

Hexafluoro-1 -propene, oxidized, polymerized. See Perfluoropolymethyl isopropyl ether... 

Synonyms 1,1,2,3,3,3-Hexafluoro-1 -propene, oxidized, polymerized 1-Propene, 1,1,2,3,3,3-hexafluoro-, oxidized, polymerized Classification Fluorine-based polymer Formula CF3(OCF3CFCF2)x(OCF2)yOCF3 Toxicology TSCA listed Uses Lubricant, emollient in cosmetics Trade Name Synonyms Fomblin HC/01 [Solvay Solexi s http //www.solvaysolexis. com] Fomblin HC/02 [Solvay Solexis http //www.solvaysolexis. com], Fom bli n HC/03 [Soivay Solexis http //www.solvaysolexis. com] Fom bli n HC/04 [Soivay Soiexis http //www.solvaysolexis.com]-, Fomblin HC/25 [Soivay Soiexis http //www.solvaysolexis. com]... 

The degradation products of GOS were 1,3-dimethyl pyrogallol (HI), 2-(2 ,6 dimethoxy phenoxy)-2-propenal (Vni), 2-(2, 6 -dimethoxy phenoxy)-3-hydroxypropanal (XII), and GOS-Dimer. These products show that the reaction includes oxidative polymerization and the cleavage of -0-4 ether linkage following the alkyl-phenyl cleavage. This depolymerization pathway of GOS is also similar to that of SOS (Table I). 

The importance of stabilizers for SCF polymerization was briefly outlined in Section 9.1.4. The drawback with existing stabilizers, however, is that most of them are based on fluorocarbons or siloxanes, which are high-cost chemicals. Cheaper polymeric stabilizers are usually only soluble in SCCO2 at pressures too high to make viable their widespread use. Very recently, Beckman and co-workers reported [68] a totally new approach to the problem polymers were prepared by co-polymerization of propene oxide and SCCO2. These polymers are not only much cheaper than fluorinated polymers but are more soluble than these materials in SCCO2. The polyether polymers are likely to have widespread applicability, not only as building blocks for stabilizers for SCF polymerization, but also as the basis of... 

Simple Lewis acid cationic catalysts, e.g. BF3, SnCl4, AIR3, PFj, SbCls etc., have been extensively used in the study of the polymerization of THF [118]. With these initiators the problem of estimating the concentration of prop ating species becomes acute, and is not made any easier by the use of so-called promoters such as propene oxide,... 

Unfortunately this simple picture does not explain all the experimental observations. For example, propene oxide will accelerate the rate of polymerization of bulk THF even when added several hours after the start of polymerization [123] indicative of the presence of a dormant species in the reaction. Mechanistic details of these co-initiation phenomena have been discussed in more detail elsewhere [124, 50]. 

A similar study was carried out by the same group [17] on propene oxide (PO) polymerization. In this case unsaturation was developed in the polymer due to a transfer reaction, but for the most part a standard head to tail polymerization occurred. At 80°C using NaOMe initiator and essentially bulk monomer, the second order rate coefficient reported was approximately 2.6 x 10" Imole" sec". The activation energy in this case was 17.4 kcal mole". ... 

A variant on this theme is to attach a transition-metal complex of a smart polymer, the solubility of which can be dramatically influenced by a change in a physical parameter, e.g., temperature [23] (cf. Sections 4.6 and 4.7). Catalyst recovery can be achieved by simply lowering or raising the temperature. For example, block copolymers of ethylene oxide and propene oxide show an inverse dependence of solubility on temperature in water [24]. Karakhanov et al. [25] prepared water-soluble polymeric ligands comprising bipyridyl (bipy) or acetylacetonate (acac) moieties covalently attached to poly(ethylene glycol)s (PEGs) or ethylene oxide/propene oxide block copolymers 9 and 10. 

CYANOPROPENE-l or 2-CYANO-l-PROPENE (126-98-7) Forms explosive mixture with air (flash point 55°F/13°C). Violent reaction with strong oxidizers. Polymerization may occur due to elevated temperature, visible light, or contact with a concentrated alkali. Contact with strong acids, strong bases, or light exposure may cause violent polymerization. Incompatible with aliphatic amines, alkanolamines, sodium nitrate. 

PHENOXY-PROPENE OXIDE (122-60-1) Combustible liquid (flash point >176 F/ >80°C). Forms unstable peroxides in air and light unless inhibitor is maintained in adequate concentrations. Contact with amines, strong acids, and strong bases may cause polymerization with spattering and the liberation of heat. Reacts violently with strong oxidizers, permanganates, peroxides, ammonium persulfate, bromine dioxide, acyl halides. Attacks some forms of plastics, coatings, and rubber. 

PROPENEOXIDE or PROPENE OXIDE (75-56-9) Forms explosive mixture with air (flash point — 35°F/—37°C), or with oxygen. Reacts with water, steam. Contact with water may lead to a run-away reaction. Able to form unstable peroxides acids, caustic materials, metal halides can cause hazardous polymerization. Reacts with acids, ammonia, amines, acetylene-forming metals, clay-based absorbents. Incompatible with anhydrous metal chlorides, caustics, ammonium hydroxide, salts. Attacks some plastics, rubber, and coatings. Flow or agitation of substance may generate electrostatic charges due to low conductivity, and may cause ignition of its vapors. 

The addition of BF3-OEt2 to an a-phosphorylated imine results in the 1,3-transfer of a diphenylphosphinoyl group, with resultant migration of the C-N=C triad. This method is less destructive than the thermal rearrangement. The decomposition of dimethyldioxirane in acetone to methyl acetate is accelerated with BF3 OEt2, but acetol is also formed. Propene oxide undergoes polymerization with BF3-OEt2 in most solvents, but isomerizes to propionaldehyde and acetone in dioxane. ... 

Propene, 1,3-dichloro-, (Z)- Propene, 1,3-dichloro-, (Z)-. See cis-1,3-Dichloro-1-propene 1-Propene, 1,1,2,3,3,3-hexafluoro-, oxidized, polymerized. See Perfluoropolymethyl isopropyl ether... 

Dehydrogenation of Propane. The demand by industry for light olefins such as propene, isobutene, ra-butene, and butadiene continues to increase. Propene is mainly used in the production of acrylonitrile or is polymerized to form polypropylene. Other important products manufactured firom propene include propene oxide, which is further converted to glycerol, and cumene, which is oxidized to phenol and acetone. 

As noted above, when Al-porphyrin complexes [97] or Zn compounds [98] are used as catalysts for the carboxylation of epoxides, the formation of polymers is observed. A1 catalysts are now used in a plant in China. The mechanism of the polymerization reaction has been studied and the most credited mechanism when Zn compounds are used is shown in Scheme 1.12. The molecular mass of the polymers varies with the catalyst. Primarily propene oxide and styrene oxide have been used so far, with some interesting applications of cyclohexene oxide. It is wished to enlarge the use of substrates in order to discover new properties of the polymers. 

When exposed to sunlight, it is converted to a white insoluble resin, disacryl. Oxidized by air to propenoic acid small amounts of hy-droquinone will inhibit this. Bromine forms a dibromide which is converted by barium hydroxide into DL-fructose. The acrid odour of burning fats is due to traces of propenal. It is used in the production of methionine and in controlled polymerization reactions to give acrolein polymers. ... 

CHjlCH COOH. Colourless liquid having an odour resembling that of ethanoic acid m.p. 13 C, b.p. I4I°C. Prepared by oxidizing propenal with moist AgO or treating -hy-droxypropionitrile with sulphuric acid. Slowly converted to a resin at ordinary temperatures. Important glass-like resins are now manufactured from methyl acrylate, see acrylic resins. Propenoic acid itself can also be polymerized to important polymers - see acrylic acid polymers. 

Small olefins, notably ethylene (ethene), propene, and butene, form the building blocks of the petrochemical industry. These molecules originate among others from the FCC process, but they are also manufactured by the steam cracking of naphtha. A wealth of reactions is based on olefins. As examples, we discuss here the epoxida-tion of ethylene and the partial oxidation of propylene, as well as the polymerization of ethylene and propylene. 

As for the Ti oxidation state after reduction with alkylaluminum compounds, literature reports are often contradictory, owing to the different catalysts and analytical methods used.108110,113 117 The only reasonable conclusion is that under polymerization conditions a considerable reduction of Ti(IV) takes place, not only to Ti(III) but to Ti(II) as well. However, Ti(II) is usually considered not to be active for propene polymerization.116... 

Propene undergoes little polymerization when treated with 96% sulfuric acid, the chief product being isopropyl hydrogen sulfate which yields isopropyl alcohol on hydrolysis. When 98% sulfuric acid is used, propylene is converted to conjunct polymer. Ethylene cannot be polymerized by sulfuric acid because the stable ethyl hydrogen sulfate and ethyl sulfate are formed attempts to obtain the polymerization by increasing the reaction temperature are unsuccessful because oxidation occurs. 

Both traditional Ziegler-Natta and metal oxide Phillips-type initiators are used in suspension polymerizations (Secs. 8-4a, 8-4j) [Kaminsky, 2001], Both types of initiators are used for ethylene, but only the traditional Ziegler-Natta initiators are used for propene since Phillips-type initiators do not yield stereoselective polymerizations. 

Propene is used as a starting material for numerous other compounds. Chief among these are isopropyl alcohol, acrylonitrile, and propylene oxide. Isopropyl alcohol results from the hydration of propylene during cracking and is the primary chemical derived from propylene. Isopropyl alcohol is used as a solvent, antifreeze, and as rubbing alcohol, but its major use is for the production of acetone. Acrylonitrile is used primarily as a monomer in the production of acrylic fibers. Polymerized acrylonitrile fibers are produced under the trade names such as Orion (DuPont) and Acrilan (Monsanto). Acrylonitrile is also a reactant in the synthesis of dyes, pharmaceuticals, synthetic rubber, and resins. Acrylonitrile production occurs primarily through ammoxidation of propylene CH3- CH = CH2 + NH3 + 1.5 02—> CH2 = CH - C = N + 3 H20. 

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