Propylene oligomers

The second source of sulfonic acid uses the following reaction scheme alkylation of benzene by a propylene oligomer then sulfonation of the alkylbenzene. 

Polymer-type antioxidants have been prepared by Eriedel-Crafts reaction of -cresol andp- and/or y -chloromethylstyrene in the presence of boron trifluoride-etherate (198). The oligomeric product resulting from the alkylation of phenyl-a-naphthylamine using C12—15 propylene oligomer in the presence of AlCl or activated white clays is used as an antioxidant additive for lubricating oils (199). 

With MAO activation, Zr- and Hf-FI catalysts 1 and 3 exhibit fairly high reactivity toward propylene and produce propylene oligomers [64, 65], Conversely, the corresponding Ti-FI catalyst/MAO 2 forms semicrystalline PP (1 °C polymerization), which displays a peak melting temperature of 97 °C, indicative of the formation of a stereoregular polymer. To our surprise, microstructural analysis by 13C NMR indicates that the resultant polymer is syndiotactic (rr 19%), and that a chain-end control mechanism is responsible for the observed stereocontrol, regardless of the C2 symmetric catalyst ([28] for the first report on syndiospecific propylene... 

The Suter-Flory model was successfully used to interpret the results of the epimerization reaction carried out on propylene oligomers (204) and on polypropylene itself (106, 205). In both cases a slight prevalence of the r dyad over the m (52/48) is observed. The epimerized polypropylene has a microstmcmre almost coincident with a Bernoulli distribution and represents the polymer sample closest to an ideal atactic polymer so far obtained. 

Coke deposits were formed from biphenyl over dealuminated HM only in the presence of propylene, although the amount of coke was less.26,27 Coke deposition occurred in a short period after starting the reaction, and by the contact of 4,4 -DIPB with HM even in the absence of propylene.26 These results suggest that the isopropylated biphenyls produce coke by dehydrogenative condensation at their isopropyl groups on acid sites. Propylene oligomers were formed during the reaction 26 They are alternative precursors of deposited coke. 

Fig. 21a and b. H NMR spectra of a iodine-terminated propylene oligomer (Mn = 630) and b HC1-terminated propylene oligomer. Chemical shifts are in ppm down-field from TMS... 

Compositions of Mixtures of Propylene Oligomers Obtained in Propylene Conversion at Various Temperatures 1... 

The propylene oligomers, starting with the trimers, are dextrorotatory. 

Alkylates made specifically as feedstocks for synthetic petroleum sulphonates are typically long chain (average C chain > 16) and may use propylene oligomers which result in branched chains. Naphthalene products use the same propylene technology but tend to shorter chains (di-isopropylnaphthalene, di-nonylnaphthalene). 

Our initial investigation included a study of the alkylation of p-cresol with propylene oligomers and with various a-olefins. Because all alkylations were carried out by a well-known procedure and neither novel reactions nor unexpected results were encountered, no detailed experimental work will be reported As shown by the following reaction, all alkylations were carried out using BF3 catalyst at 80°-90°C. and excess olefin as the reaction solvent. 

Differently, in the case of secondary chain growth with bis(phenoxy-imine)titanium catalysts, Coates and coworkers reported that chain release occurs exclusively by /3-H hydride transfer from the terminal methyl. This generates an allylic end group as shown in Scheme 15,160 and it has been utilized to produce functionalized syndiotactic propylene oligomers.258... 

Shell produces C, to C, carboxylic acids marketed under the trade name Versatic acids. Exxon carbonylates propylene oligomers to produce neo acids. The derivatives and markets for these products are described in this chapter under the section on oxo chemicals. 

The propylene oligomerization literature is considerably poorer than that for the ethylene oligomerization. The catalysts for oligomerization of propylene are also active in ethylene oligomerization. Also in this case, the titanium, zirconium, and nickel complexes are the most popular catalysts. Propylene oligomers are more structurally diverse than ethylene oligomers. 

Aladyshev, A. M., Lisitsyn, D. M., and Dyachkovskyi, E S., Formation of propylene oligomers during the polymerization process, Vysokomol Soedin., A, 24, 377, 1982 (Russian). 

Journal of Applied Polymer Science 71,No.3, 18th Jan.l998,p.371-5 PROPYLENE OLIGOMERS EXTRACTION METHODS AND CHARACTERISATION BY FTIR, HPLC, AND SEC... 

Details are given of the isolation of propylene oligomers from polymer matrix by dissolution precipitation and Soxhlet methods. Characterisation was undertaken by FTIR, UV spectroscopy, HPLC, and GPC. Data were used to explain their behaviour toward packaged food products in PP packaging. 18 refs. 

The polymeric surfactants (HFPO) Ar, where (HFPO) is a hexafluoro-propylene oligomer and Ar an aryl group [52,173], lower the surface tension of hydrocarbons such as w-xylene and belong, therefore, to the class of hydrophile-free surfactants (see Section 1.9). 

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