Propylene oxide, oligomerization

These products are characterized in terms of moles of substitution (MS) rather than DS. MS is used because the reaction of an ethylene oxide or propylene oxide molecule with ceUulose leads to the formation of a new hydroxyl group with which another alkylene oxide molecule can react to form an oligomeric side chain. Therefore, theoreticaUy, there is no limit to the moles of substituent that can be added to each D-glucopyranosyl unit. MS denotes the average number of moles of alkylene oxide that has reacted per D-glucopyranosyl unit. Because starch is usuaUy derivatized to a considerably lesser degree than is ceUulose, formation of substituent poly(alkylene oxide) chains does not usuaUy occur when starch is hydroxyalkylated and DS = MS. 

Diaminopropane Processes. 1,2-Propylenediamine can be produced by the reductive amination of propylene oxide (142), 1,2-propylene glycol [57-55-6] (143), or monoisopropanolamine [78-96-6] (144). 1,3-Propanediol [504-63-2] can be used to make 1,3-diaminopropane (143). Various propaneamines are produced by reducing the appropriate acrylonitrile—amine adducts (145—147). Polypropaneamines can be obtained by the oligomerization of 1,3-diaminopropane (148,149). 

Wood wafers were treated with mixtures of propylene oxide and oligomeric isocyanate (Guevera and Moslemi, 1983). The best treatment was found to be a mixture of 9 1 propylene oxide to isocyanate. In another study, Guevera and Moslemi (1984) studied the swelling properties of wood modified with propylene or butylene oxide and compared the data with modifications using a furan resin, or vinylpyrrolidinone. The best results were obtained by the use of alkylene oxides in combination with a cross-linking agent (trimethylol propane trimethacrylate). 

Guevera, R., and Moslem , A.A. (1983). Hygroexpansive and sorptive behaviour of wood modified with propylene oxide and oligomeric diisocyanate. Journal of Wood Chemistry and Technology, 3(1), 95-114. 

There are other commercial processes available for the production of butylenes. However, these are site or manufacturer specific, eg, the Oxirane process for the production of propylene oxide the disproportionation of higher olefins and the oligomerization of ethylene. Any of these processes can become an important source in the future. More recendy, the Coastal Isobutane process began commercialization to produce isobutylene from butanes for meeting the expected demand for methyl-tert-buty ether (40). 

Oligomeric agents were prepared by condensing trimethylolpropane with ethylene and/or propylene oxides and capping with acrylic acid. These materials were subsequently crosslinked using 2,2 -azobisamidinopropane dihydrochloride, which formed superabsorbent swellable hydrogel addition polymers and were useful as components in diapers or in feminine hygiene products. 

Figure 1. 1H-NMR spectrum of a living oligomeric propylene oxide prepared with TPPAICI. (Reproduced from Ref. 6. Copyright 1981 American Chemical Society.)...

The diisocyanates are used mainly in the manufacture of polyurethanes (PUR). These are produced by polyaddition of diisocyanates and dihydric alcohols, in particular the polyether alcohols (i.e., polyethylene glycols, polypropylene glycols, and the reaction products of propylene oxide with polyhydric alcohols). In addition, oligomeric esters from dicarboxylic acids and diols (polyester alcohols) are also used [91] ... 

Kinetic analysis of main reactor in dependence on used catalytic system showed (see 5.2) that under oligomerization of piperylene initiated by AICl3-0(C6H5)2 it is advisable to use tubular turbulent apparatus. Not high values of dynamic viscosity of liquid oligo-piperylene rubber at output of reactor (at 283 K, i = 1 mPa Sec) allows also perfecting of stage of catalyst deactivation by propylene oxide or water (Fig. 6.8b). 

ME1 Medved, Z.N. and Starikova, N.A., Enthalpies of mixing of oligomeric propylene oxides and water (Russ.), Zh. Fiz. Khim., 57, 2590, 1983. 

N,N, N"-Tris(trimethylsilyl)diethylenetriamine complexes of aluminum have been shown to be active oligomerization catalysts for propylene oxide. Over the course of 2 days, catalyst 6 (Figure 1) produces low-molecular-weight poly (propylene oxide) (A n<500gmor ) with predominantly head-to-tail linkages and an m-dyad content of 60%. 

Propylene oxide undergoes similar ringopening polymerization. The products are less soluble in water than the corresponding polyethylene oxides. They serve as toughening soft segments in polyurethanes when they are polymerized with oligomeric diisocyanates. 

Bian, Y., Pejanovic, S., Kenny, J., Mijovic, J. Dynamics of multifunctional polyhedral oligomeric silsesquioxane/poly(propylene oxide) nanocomposites as studied by dielectric relaxation spectroscopy and d5mamic mechanical spectroscopy. Macromolecules 40 (2007) Boucher, V.M., Cangialosi, D., Alegria, A., Colmenero, J. Time dependence of the segmental relaxation time of poly(vinyl acetate)-silica nanocomposites. Phys. Rev. E 86, 041501 (2012)... 

A liquid-type, concentric capacitor coil, dielectric cell was used for all of these studies. Thus, much of the work employed highly plasticized mixtures of the polymer sample of interest. The exception to this was the work by Varadaiajan et al. on oligomeric poly(propylene oxide)s which retained acceptable levels of fluidity down through their transition temperature range. Values of capacitance and dielectric loss were measured using a Hewlett-Packard LCR meter at... 

Ans Ethylene a-alkenes (oligomerization), acetaldehyde (oxidation) propylene n-butyraldehyde (hydroformylation), propylene oxide (epoxidation) CO acetic acid, acetic anhydride (carbonylation). 

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