Alkylene oxide polymerization using aluminum compounds and phosphorus-nitrogen bases

Abstract

The present invention provides a polyether prepared by polymerizing alkylene oxide in the presence of an initiator, an aluminum compound having at least one hydrocarbyl substituent, and a phosphorus-nitrogen base. The molar ratio of the amount of the phosphorus-nitrogen base present to the amount of the initiator is small. The presence of such a small amount of phosphorus-nitrogen base greatly improves the catalytic activity of the system compared to the case where the aluminum compound is used alone. The product polyether has a small amount of unsaturated polyether impurities and little or no unwanted high molecular weight portion. The proportion of primary hydroxyl groups of the propylene oxide polymer is very low.

Description

[0001] The present invention relates to a process for polymerizing one or more alkylene oxides or copolymerizing one or more alkylene oxides with one or more copolymerizable monomers which are not alkylene oxides.

[0002] Alkylene oxide polymers and copolymers are produced in large quantities worldwide. For example, polyether polyols are important raw materials for the production of polyurethanes. Among other things, they are used to make high-resistance foams, molded foams or rigid foams. For example, polyether monools are used as surfactants and industrial solvents, among others. Carbonate-modified alkylene oxide polymers and ester-modified alkylene oxide polymers are also found in these and other applications.

[0003] Polyether mono-ols and polyether polyols are produced by polymerizing alkylene oxides in the presence of initiator compounds. The initiator compounds have one or more functional groups at which the alkylene oxides can react to begin forming polymer chains. The main function of the initiator compound is to provide molecular weight control and to determine the number of hydroxyl groups that the polyether will have.

[0004] Catalysts are required to obtain economical polymerization rates.The most commonly used catalysts are alkali metal hydroxides (such as potassium hydroxide) and the so-called double metal cyanide (DMC) catalyst complexes, of which zinc hexacyanocobaltate catalyst complexes are the commercially most important type.

[0005] Alkali metal hydroxides provide the beneficial effects of low catalyst cost and acceptable polymerization rate. They are widely used because they can effectively polymerize many alkylene oxides. The product polyethers usually but not always have a narrow molecular weight distribution. The unique advantage of these catalysts is that they can be used to polymerize ethylene oxide to alcohols initiators. This ability is quite important in industry because many polyether polyols manufactured as polyurethane raw materials are block copolymers made by polymerizing propylene oxide and then ethylene oxide to the initiator compound. Alkali metal hydroxide catalysts make this process easy and cheap because these two polymerizations can be carried out in the same container using the same catalyst system without the need to recycle the intermediate poly (propylene oxide) polyol.

[0006] Nevertheless, alkali metal hydroxides still have well-known disadvantages. Alkali metal hydroxide catalysts promote side reactions that form unsaturated monoalcohols, which can be alkoxylated to form unwanted monofunctional species. The presence of these unwanted monofunctional species can also broaden the molecular weight distribution. The polyols made using these catalysts need to be neutralized and purified to remove catalyst residues, which adds a lot of cost and operating expenses to the manufacturing process. In addition, the product polyethers tend to have a broad molecular weight distribution when prepared in a backmixed continuous process.

[0007] Compared to alkali metal catalysts, DMC catalysts provide rapid polymerization rates, even when used at very low catalyst concentrations. In addition, they have different and important advantages over alkali metal catalysts. DMC catalysts rarely, if ever, promote side reactions that produce monofunctional by-products, so the hydroxyl functionality of the product is close to the theoretical value (as defined by the initiator). A second major advantage is that no neutralization step is required. Unlike when alkali metal hydroxides are used as polymerization catalysts, catalyst residues can usually be left in the product. This can result in a significant reduction in production costs. A third advantage is that, unlike alkali metal hydroxide catalysts, DMC catalyst complexes can produce polymers with low polydispersity when polymerization is carried out in a backmixed continuous main reactor.

[0008] Nevertheless, DMC catalysts also have disadvantages. DMC catalysts tend to perform poorly in the presence of high concentrations of hydroxyl groups, especially in the presence of low molecular weight initiator compounds such as glycerol having hydroxyl groups located in the 1,2-position or 1,3-position relative to each other. Under these conditions, the catalyst is difficult to activate, is slow to act, and is often deactivated before polymerization is complete. This has placed significant limitations on the widespread adoption of DMC catalysts. It is often necessary to produce the polyethers in two or more separate steps, wherein the early stages of the polymerization are carried out in the presence of an alkali metal catalyst and, after cleaning up the resulting intermediate product, the remainder of the polymerization is carried out using a DMC catalyst. This approach requires neutralization and purification of the intermediate (because DMC catalysts are deactivated by strong bases), thereby reintroducing the costs that DMC-catalyzed polymerizations are intended to avoid.

[0009] Another very significant disadvantage of DMC catalysts is that they cannot be used on an industrial scale to produce ethylene oxide-terminated polyethers. Ethylene oxide tends to produce poly(ethylene oxide) polymers of very high molecular weight, rather than adding to the chain ends in a regular and controlled manner. Despite many attempts to address this problem, it has not been solved satisfactorily, and ethylene oxide-terminated polyethers are almost always prepared on an industrial scale using alkali metal hydroxide catalysts for the capping step.

[0010] Another problem associated with DMC catalysts is that they produce only small amounts of very high molecular weight (40,000+ g / mol) polymers. The presence of these polymers increases polyol viscosity, broadens molecular weight distribution, and can also adversely affect the ability of polyether polyols made with DMC catalyst complexes to produce flexible polyurethane foams.

[0011] Certain Lewis acids have been evaluated as alkylene oxide polymerization catalysts. These Lewis acids require essentially no activation time, but deactivate rapidly and therefore fail to produce high molecular weight polymers or to provide a high degree of conversion of the alkylene oxide to polymer. In addition, poly(propylene oxide) polymers produced by Lewis acid catalysis tend to have a large proportion of primary hydroxyl groups.

[0012] Furthermore, various aluminum compounds have been described for use as alkylene oxide polymerization catalysts.

[0013] The polymerization of propylene oxide in the presence of a poly(propylene oxide) initiator compound, triisobutylaluminum and a phosphazene base is described in Polym. Chem., 2012, Vol. 3, pp. 1189-1195. The polymerization is carried out in a toluene solution at 20°C. The amount of phosphazene base used is large, about one mole per equivalent of initiator. U.S. Published Patent Application No. 2018-0237586 describes another solution polymerization of propylene oxide in the presence of trialkylaluminum and nitroalkoxide, wherein the latter nitroalkoxide is described as an initiator. Similarly, the amount of nitroalkoxide used is also large. A high molecular weight polyether with a wide molecular weight distribution is obtained.

[0014] Macromolecules, 2008, Vol. 41, pp. 7058-7063, describes the polymerization of epichlorohydrin at temperatures up to room temperature and in the absence of initiators using triisobutylaluminum compounds and in the presence of tetraoctylammonium bromide.

[0015] US Patent No. 6,919,486 describes the polymerization of propylene oxide in the presence of a polyether triol initiator and an aluminum phosphonate catalyst. Ethylene oxide capping is also described. These polymerization processes are carried out at a temperature of 110° C. in the absence of solvent.

[0016] Macromolecules, 1974, Vol. 7, pp. 153-160, describes the low-temperature polymerization of propylene oxide in bulk form in the presence of aluminoxanes such as (C2H5)2AlOAl(C2H5)2(TEDA). No initiator is mentioned. Polyethers with molecular weights of 100,000 to 1 million are obtained. J. Polym. Sci., 1973, Vol. 11, pp. 699-712, describes the polymerization of propylene oxide in solution at 40°C using TEDA in the absence of an initiator.

[0017] Diethylaluminium chloride is described as an alkylene oxide polymerization catalyst in US 3,029,216 in solution polymerizations at temperatures up to 110°C without initiators and in J. Polym. Sci., 1959, Vol. 34, pp. 157-160 in bulk polymerizations at 25°C without initiators. High molecular weight polymers are obtained.

[0018] The invention is in one aspect a method for producing an alkylene oxide polymer or copolymer, the method comprising: combining (i) at least one aluminum compound containing at least one trisubstituted aluminum atom, wherein at least one of the substituents of the at least one trisubstituted aluminum atom is a hydrocarbon group, (ii) at least one initiator, (iii) at least one alkylene oxide, (iv) 0.00005 mole to 0.1 mole of at least one phosphazene-nitrogen base per equivalent of initiator, and optionally (v) at least one comonomer that is not ethylene oxide, and polymerizing the alkylene oxide or copolymerizing the alkylene oxide with the comonomer to form the alkylene oxide polymer or copolymer.

[0019] The method of the present invention provides several advantages from both a process and a product perspective.

[0020] Process advantages include: rapid polymerization rates; the ability to alkoxylate a wide range of starters, particularly low molecular weight starters having hydroxyl equivalent weights of 30 to 75; the ability to use much lower levels of catalyst than required with alkali metal hydroxides, thereby reducing costs and allowing the use of polyols without first removing catalyst residues, at least in some cases; the ability to use higher URO (unreacted alkylene oxide) levels than with DMC catalysts without forming unwanted higher molecular weight polymers; and the ability of the catalyst to polymerize ethylene oxide uniformly. This last advantage is very important in the industry, given the difficulty in polymerizing ethylene oxide with double metal cyanide catalysts. The ability to homogeneously polymerize ethylene oxide permits the catalyst to be used to prepare ethylene oxide-terminated polyols having a high proportion of primary hydroxyl groups, and permits the use of a single catalyst for the polymerization steps of propylene oxide, butylene oxide, propylene oxide-co-ethylene oxide and / or butylene oxide-co-ethylene oxide and the end-capping (ethoxylation) step to prepare ethylene oxide-terminated poly(propylene oxide) polyols, ethylene oxide-terminated poly(butylene oxide) polyols, ethylene oxide-terminated poly(propylene oxide-co-ethylene oxide) polyols, and ethylene oxide-terminated poly(butylene oxide-co-ethylene oxide) polyols.

[0021] From a product perspective, the advantages of the present invention include: i) polydispersity (M w / M n ) low; ii) the absence of the "high molecular weight tail" that occurs in DMC-catalyzed polymerizations; iii) less unwanted monofunctional species formed due to isomerization of alkylene oxides to unsaturated alcohols; and iv) when propylene oxide is homopolymerized, polyethers having a very low proportion of primary hydroxyl groups are produced.

[0022] The aluminum compound is an aluminum compound comprising at least one trisubstituted aluminum atom. At least one, at least two or all three substituents of at least one trisubstituted aluminum atom are hydrocarbon groups. Two or more of the substituents on the trisubstituted aluminum atom may form a ring structure together.

[0023] The aluminum compound may contain 1, 2, 3, 4 or more aluminum atoms (such as up to 100, up to 50, up to 25, up to 12 or up to 5 aluminum atoms), wherein at least one aluminum atom is trisubstituted.

[0024] The hydrocarbyl substituent can be aliphatic, alicyclic, aromatic or any combination of two or more thereof, and the hydrocarbyl substituent is bonded to the aluminum atom through an aluminum-carbon bond. The hydrocarbyl substituent has up to 12, up to 6 or up to 4 carbon atoms in some cases. The hydrocarbyl can be, for example, a straight chain alkyl or a branched chain alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, etc. The hydrocarbyl substituent can be unsubstituted or inertly substituted.

[0025] The non-hydrocarbyl substituents bonded to the aluminum atom(s) may be, for example, halogen, phosphonate, hydride, oxo (ie, -O-), alkoxy, or phenoxy.

[0026] A halogen substituent may be, for example, fluorine, chlorine, bromine or iodine.

[0027] An alkoxy substituent or a phenoxy substituent may have -OR 2 or -O(-R 2 -O) z -R 2 -OZ form, where each R 2 is independently a hydrocarbon group or a substituted hydrocarbon group, z is zero or a positive number, Z is a hydrocarbon group, an inert substituted hydrocarbon group, hydrogen or -AlY2, wherein each Y is a halogen, a hydrocarbon group, a phosphonate, hydrogen, an oxo group (i.e., -O-) or an alkoxy or phenoxy group. The alkoxy or phenoxy group may include a polyether chain, such as a poly(ethylene oxide) or poly(propylene oxide chain). Specific examples of alkoxy substituents or phenoxy substituents include ethoxy, n-propoxy, isopropoxy, butoxy, n-butoxy, isobutoxy, phenoxy, 2,6-di-tert-butyl-4-methylphenoxy, 2,6-diisopropylphenoxy, 2,6-diphenylphenoxy, 2,4,6-trimethylphenoxy, 4-fluorophenoxy, 4-chlorophenoxy, 3,4,5-trifluorophenoxy,

[0028] Where R 3 is hydrogen, phenyl or C 1-4 alkyl, and z is as described above, and

[0029] Any of these substituents, except hydrides, can form all or part of a connecting bridge between aluminum atoms. Thus, for example, an oxo (-O-) group can bond two aluminum atoms to form an aluminoxane. Similarly, a divalent hydrocarbon radical can bond to two aluminum atoms to form a connecting bridge between them, such as -OR 2 -O-diradical or -O-(R 2 -O) z -R 2 -O-diradical.

[0030] In some embodiments, at least one aluminum atom is substituted with one or two hydrocarbyl groups and substituted with one or two halogen, oxo, ether, hydride or phosphonate groups. If there is more than one aluminum atom in the aluminum compound, all aluminum atoms may be substituted in this manner.

[0031] Specific examples of aluminum compounds include trimethylaluminum, triethylaluminum, triisopropylaluminum, tri-n-propylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-tert-butoxyaluminum, trioctadecylaluminum, dimethylaluminum chloride, methylaluminum dichloride, diethylaluminum chloride, ethylaluminum dichloride, diisobutylaluminum chloride (DIBAL), isobutylaluminum dichloride, di[(2,6-di-tert-butyl-4-methyl)phenoxy]methylaluminum (Al(BHT)2Me), 2,6-di-tert-butyl-4-methylphenoxydimethylaluminum (AlBHTMe2), di( 2,6-diisopropyl)phenoxymethylaluminum, (2,6-diisopropyl)phenoxydimethylaluminum, bis[(2,6-diphenyl)phenoxy]methylaluminum, (2,6-diphenyl)phenoxydimethylaluminum, bis[(2,4,6-trimethyl)phenoxy]methylaluminum, (2,4,6-trimethyl)phenoxydimethylaluminum, tetraethylaluminum, tetramethylaluminum, diisobutylaluminum hydride, isobutylaluminum dihydride, dimethylaluminum hydride, methylaluminum dihydride, diethylaluminum hydride, ethylaluminum dihydride, diisopropylaluminum hydride, isopropylaluminum dihydride, diethyl Aluminum dimethoxy, ethyl diethoxyaluminum, dimethyl aluminum ethoxy, methyl diethoxyaluminum, dimethyl aluminum fluoride, methyl aluminum difluoride, diethyl aluminum fluoride, ethyl aluminum difluoride, diisobutyl aluminum fluoride, isobutyl aluminum difluoride, dimethyl aluminum bromide, methyl aluminum dibromide, diethyl aluminum bromide, ethyl aluminum dibromide, diisobutyl aluminum bromide, isobutyl aluminum dibromide, dimethyl aluminum iodide, methyl aluminum diiodide, diethyl aluminum iodide, ethyl aluminum diiodide, diisobutyl aluminum iodide, isobutyl aluminum iodide, bis(dimethylaluminum) methylphosphonate, bis(diethylaluminum) methylphosphonate, bis(diethoxyaluminum)methylphosphonate, bis(di-n-propylaluminum)methylphosphonate, bis(diisopropylaluminum)methylphosphonate, bis(di-n-propoxyaluminum)methylphosphonate, bis(diisopropoxyaluminum)methylphosphonate, bis(di-tert-butylaluminum)methylphosphonate, bis(di-tert-butoxyaluminum)methylphosphonate, bis(diphenylaluminum)methylphosphonate, bis(diphenoxyaluminum)methylphosphonate, bis(diisobutylaluminum)methylphosphonate, and tetraalkylaluminoxanes, wherein each alkyl group of the tetraalkylaluminoxane independently contains 1 to 6 carbon atoms.

[0032] For purposes of the present invention, an "inert" substituent is one that does not react with hydroxyl, amino or isocyanate groups. Examples of inert substituents include, for example, hydrocarbyl substituents, ether groups, ester groups, tertiary amino groups, amide groups, halogens, and the like.

[0033] For purposes of the present invention, a "phosphorus-nitrogen base" is a compound having at least one -NPN- bond and / or at least one -PNP- bond, wherein the bond between the phosphorus and the adjacent nitrogen atom is independently a single bond or a double bond. For example, the -NPN- bond may be in the form of -NPN- (both nitrogen-phosphorus bonds are single bonds) or -N=PN-, and the -PNP- bond may be in the form of -PNP-, -P=NP- or -P=N + =P-. Alternating nitrogen and phosphorus atoms can form a ring structure having, for example, 3 to 10 phosphorus atoms and 3 to 10 nitrogen atoms.

[0034] The phosphorus-nitrogen base may comprise, for example, 1 to 8, 1 to 4, or 1 to 2 phosphorus atoms and 1 to 12 or 1 to 8 nitrogen atoms, provided that the total number of nitrogen atoms plus phosphorus atoms is at least 3. The phosphorus-nitrogen base may have a molecular weight (excluding any anionic counterions) of up to 1000 g / mol, 750 g / mol, or 650 g / mol. In some embodiments, the molecular weight is up to 500 g / mol or up to 350 g / mol.

[0035] Phosphorus-nitrogen bases can be neutral or can be cationic. When cationic, the charge can reside on the nitrogen or phosphorus atom, or can be delocalized. When the phosphorus-nitrogen base is cationic, it is generally used in the form of a salt formed with an anionic counter ion. The counter anion is preferably not alkoxylated under the conditions of alkylene oxide polymerization, and in particular preferably not an alkoxy or aryloxy group. Examples of useful counter ions include halides (such as fluoride, chloride, bromide and iodide), nitrate, bisulfate, carbonate, hexafluorophosphate, bis(trifluoromethylsulfonyl)imide, trifluoromethanesulfonate, etc. The counter ion is preferably monovalent.

[0036] The nitrogen atom is preferably alkyl-substituted, and more preferably alkylated, to the extent that it is bonded to a substituent other than phosphorus, i.e., all substituents that are not phosphorus on each nitrogen atom in the nitrogen atom are preferably alkyl-substituted, and more preferably alkyl-substituted. Any alkyl group can be substituted by inertia. The alkyl substituent can have, for example, 1 to 18 carbon atoms, wherein a preferred number is 1 to 8 carbon atoms or 1 to 4 carbon atoms. The substituents on the nitrogen atom of the phosphorus-nitrogen base can all be identical, or two or more different substituents can be present. In addition, any two alkyl substituents on a single nitrogen atom or on two different nitrogen atoms can form a ring structure comprising one or more nitrogen atoms.

[0037] The phosphorus atom, to the extent that it is bonded to a substituent other than nitrogen, may be bonded to an oxygen atom (such as to form a P=O bond, for example, or to an oxygen atom of an aryloxy, alkoxy, or phosphate substituent) or to a hydrocarbyl substituent. Any hydrocarbyl group may be inertly substituted. Hydrocarbyl substituents include phenyl; alkyl-substituted phenyl; alkyl groups, preferably having 1 to 18, 1 to 8, or 1 to 4 carbon atoms, and phenyl-substituted alkyl groups, wherein the alkyl group has 1 to 18, 1 to 8, or 1 to 4 carbon atoms.

[0038] Suitable phosphorus-nitrogen bases are those represented by structure I:

[0039]

[0040] Wherein each R is a hydrocarbon group, especially having up to 18 or up to 8 carbon atoms, NH2 or -N=P-R3, A is an anion, and n is the valence of anion A, and the base has a molecular weight as described above (excluding the mass of counterion A). Any hydrocarbon group can be inertly substituted. In some embodiments, each R is a phenyl group, and anion A is monovalent, especially a halogen. Specific examples of this type of phosphorus-nitrogen base are bis(triphenylphosphinoalkyl)ammonium salts, especially salts of monovalent anions A, such as fluorides, chlorides, bromides, iodides, acetates, trifluoromethanesulfonates, BF4 - or PF6 - .

[0041] Another class of suitable phosphorus-nitrogen bases includes those represented by structure II:

[0042]

[0043] Where R 5 and each R 4 independently -P[N(R 4 )2]3 or a hydrocarbon group (more preferably an alkyl group or an alkylene group), provided that any two hydrocarbon groups R 4 The group may form a divalent hydrocarbon group, which forms a divalent hydrocarbon group containing such R 4 The alkyl or alkylene substituents may have, for example, 1 to 18 carbon atoms, with the preferred number being 1 to 8 carbon atoms or 1 to 4 carbon atoms. Any hydrocarbon group may be inertly substituted. 5 and each R 4 R is independently, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, n-octyl, isooctyl, 1,1,3,3,3-pentamethylpropyl, etc. In some embodiments, each R 4 is methyl, and R 5 is a C1 to C8 straight or branched alkyl group. x is zero or a positive number and is5 and R 4 The groups are selected together so that the base has a molecular weight as previously described. x is preferably 0, 1, 2 or 3.

[0044] Specific examples of phosphorus-nitrogen bases having structure II include methylimino-tris(dimethylamino)phosphorane, ethylimino-tris(dimethylamino)phosphorane, tert-butylimino-tris(dimethylamino)phosphorane (PAZ-P1), tert-octylimino-tris(dimethylamino)phosphorane, phosphazene base P2 (corresponding to structure II, wherein x is 1 and each R 4 and R 5 is methyl), phosphazene base P2-ethyl (corresponding to structure II, wherein x is 1, each R 4 is methyl, and R 5 ethyl), phosphazene base P2-tert-butyl (corresponding to structure II, wherein x is 1, each R 4 is methyl, and R 5 tert-butyl), phosphazene base P2-tert-octyl (corresponding to structure II, wherein x is 1, each R 4 is methyl, and R 5 1,1,3,3,3-pentamethylpropyl), ethylimino-tri(pyrrolidinyl)phosphorane, tert-butylimino-tri(pyrrolidinyl)phosphorane, tert-octylimino-tri(pyrrolidinyl)phosphorane, 2-ethylimino-2-diethylamino-1,3-dimethylperhydro-1,3-2-diazaphosphine, 2-tert-butylimino-2-diethylamino-1,3-dimethylperhydro-1,3-2-diazaphosphine, 2-tert-octylimino-2-diethylamino-1,3-dimethylperhydro-1,3-2-diazaphosphine, phosphazene base P4 (1-methyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)-phosphoranilin]-2λ 5 , 4λ 5 - cyclic bis(phosphazene)), phosphazene base P4-ethyl (1-ethyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)-phosphoranilin]-2λ 5 , 4λ 5 - cyclic bis(phosphazene)) and phosphazene base P4-tert-butyl (1-tert-butyl-4,4,4-tris(dimethylamino)-2,2-bis[tris(dimethylamino)-phosphoranilino]-2λ 5 , 4λ 5 - cyclic bis(phosphazene)).

[0045] Other useful phosphorus-nitrogen bases include phosphoramides represented by structures III and / or IIIa:

[0046]

[0047] Each R 4 As described above with respect to Structure I, R 10 is a hydrocarbon group or an inertly substituted hydrocarbon group as described above, and wherein the molecular weight of the phosphoramide is as described above. 4 For example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, 1,1,3,3,3-pentamethylpropyl, and any two R 4 The groups can be combined to form a divalent hydrocarbon group, which forms a divalent hydrocarbon group containing such R 4 Specific examples of such phosphoramide compounds include hexamethylphosphoramide (tris(dimethylaminophosphine oxide)), hexaethylphosphoramide, hexa-tert-butylphosphoramide, and tris(N,N-tetramethylene)phosphoramide.

[0048] Other suitable phosphorus-nitrogen bases are those represented by structure IV:

[0049]

[0050] wherein A and n are as described above for Structure II, and each R 6 are independently a hydrocarbon group (more preferably an alkyl group), or N=P-(NR 6 2)3, further condition is that any two R 6 The group may form a divalent hydrocarbon group, which forms a divalent hydrocarbon group containing such R 6 The molecular mass of the phosphorus-nitrogen base having structure IV (excluding the mass of the counterion A) is as above.

[0051] Examples of phosphorus-nitrogen bases having structure IV include phosphazene base P2-F (1,1,1,3,3,3-hexa(dimethylamino)diphosphazene fluoride), phosphazene base P2-Cl (1,1,1,3,3,3-hexa(dimethylamino)diphosphazene chloride), phosphazene base P2-Br (1,1,1,3,3,3-hexa(dimethylamino)diphosphazene bromide), phosphazene base P5-F (tetrakis[tris(dimethylamino)phosphoranilino]phosphonium fluoride), phosphazene base P5-Cl (tetrakis[tris(dimethylamino)phosphoranilino]phosphonium chloride), and phosphazene base P5-Br (tetrakis[tris(dimethylamino)phosphoranilino]phosphonium bromide).

[0052] Another class of phosphorus-nitrogen bases includes phosphine compounds represented by structures V and / or VI:

[0053]

[0054] Each R 7 are independently hydrocarbon groups, and more preferably alkyl groups, provided that any two hydrocarbon groups R 7The group may form a divalent hydrocarbon group, which forms a divalent hydrocarbon group containing such R 7 The alkyl or alkylene substituents may have, for example, 1 to 18 carbon atoms, with a preferred number being 1 to 8 carbon atoms or 1 to 4 carbon atoms. Each R 7 R is independently, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, n-octyl, isooctyl, 1,1,3,3,3-pentamethylpropyl, etc. In some embodiments, each R 4 Examples of the phosphine having structure V include tris(dimethylamino)phosphine, tris(diethylamino)phosphine, tris(di-tert-butylamino)phosphine, and the like.

[0055] Another class of suitable phosphorus-nitrogen bases includes cyclic compounds represented by structure VII:

[0056]

[0057] wherein m is a number from 3 to 20, preferably from 3 to 10, more preferably from 3 to 5, and most preferably 3. Each Q is independently selected from a hydrocarbon group, especially having up to 18 or up to 8 carbon atoms; -N=P-R3, wherein R is a hydrocarbon group, preferably having up to 18 or up to 8 carbon atoms, an aryloxy group; an alkoxy group, and

[0058]

[0059] Where c is zero or preferably a positive number up to 4, each R 9 are independently hydrocarbons, especially having 1 to 18, 1 to 8 or 1 to 4 carbon atoms, or hydrogen, and each R 8 is independently a hydrocarbon, especially having 1 to 18, 1 to 8 or 1 to 4 carbon atoms. 9 is preferably hydrogen or methyl, and each R 8 Preferred are alkyl or phenyl groups having up to 4 carbon atoms. Phosphorus-nitrogen bases having structure VII include those described in US Published Patent Application No. 2011-0130497, which is incorporated herein by reference.

[0060] Polymerization is carried out in the presence of one or more initiator compounds. The initiator compound has one or more functional groups that can be alkoxylated. The initiator can contain any large number of such functional groups. These functional groups can be, for example, primary hydroxyl, secondary hydroxyl or tertiary hydroxyl, primary amino, secondary amino or mercaptan. Preferred initiators contain 1 or more such functional groups, preferably contain 2 or more such functional groups, and can contain up to 12 or more such functional groups.

[0061] In certain embodiments, these functional groups are all hydroxyl groups, and the initiator does not contain primary and / or secondary amino groups or thiol groups. In some embodiments, the initiator compound will have 2 to 8, 2 to 4, or 2 to 3 hydroxyl groups.

[0062] In certain embodiments, these functional groups are all primary and / or secondary amine groups, and the initiator does not contain hydroxyl or thiol groups.In some embodiments, the initiator compound will have 2 to 8, 2 to 4 or 2 to 3 primary and / or secondary amine groups.

[0063] The equivalent of each functional group of the initiator compound is less than the equivalent of each functional group of the polyether product. Its equivalent can be 9 (with respect to water) to 6000 or greater. In some embodiments, the equivalent of the initiator compound is 9 to 4000, 9 to 2500, 30 to 1750, 30 to 1400, 30 to 1000, 30 to 500 or 30 to 250.

[0064] The equivalent weight of an alcohol or polyol is conveniently determined using a titration method such as ASTM 4274-16 which yields the hydroxyl number in the form of mg KOH / g polyol which can be converted to equivalent weight using the following relationship: Equivalent Weight = 56,100 ÷ Hydroxyl Number.

[0065] Suitable initiators include vinyl alcohol, propenyl alcohol, allyl alcohol, acrylic acid, hydroxyethyl acrylate, hydroxyethyl methacrylate, C 1-50 Alkanols, phenol, cyclohexanol, alkylphenols, water (which has two hydroxyl groups for the purposes of the present invention), ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, cyclohexanedimethanol, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, sucrose, phenol, polyphenol initiators (such as bisphenol A) or 1,1,1-tris(hydroxyphenyl)ethane, and the like.

[0066] Other suitable starters are amine compounds such as morpholine, piperidine, piperazine, toluenediamine (any isomers or mixtures of isomers), phenylenediamine (any isomers or mixtures of isomers), diethyltoluenediamine, ethylenediamine, diethylenetriamine, higher polyethylene polyamines having up to 8 nitrogen atoms, 1,3-propylenediamine, 1,2-propylenediamine, 1,4-butylenediamine, cyclohexanediamine, isophoronediamine, bis(aminomethyl)cyclohexane and bis(3-aminopropyl)methylamine.

[0067] Still other suitable initiators are hydroxyl-terminated polyethers (including alkoxylates, especially ethoxylates and / or propoxylates, of hydroxyl-containing initiators and / or amine initiators (including those described previously)), whose hydroxyl equivalent weight is less than the hydroxyl equivalent weight of the polymerized product. The hydrogen group equivalent weight of such polyether initiators is, for example, at least 125 g / equivalent and at most 6000 g / equivalent, at most 4000 g / equivalent, at most 2500 g / equivalent, at most 1750 g / equivalent, at most 1500 g / equivalent, at most 1000 g / equivalent, at most 500 g / equivalent, or at most 250 g / equivalent. In some embodiments, the polyether initiator can be a homopolymer of propylene oxide and / or a random or block copolymer of propylene oxide and one or more other alkylene oxides, especially ethylene oxide, having a hydroxyl equivalent weight as described in this paragraph, and wherein no more than 25%, no more than 15%, or no more than 10% of the hydroxyl groups are primary hydroxyl groups.

[0068] In some embodiments, the aluminum compound is soluble in the initiator in the proportion at the start of polymerization. The solubility is assessed by mixing the aluminum compound with the initiator in an appropriate proportion and stirring for 15 minutes at up to 160° C., preferably up to 75° C. Upon visual inspection, the formation of a clear liquid indicates that the aluminum compound is soluble in the initiator.

[0069] Similarly, in some embodiments, the phosphorus-nitrogen base is soluble in the initiator in the proportions at which polymerization is started, and the solubility is assessed in the same manner as previously described for the aluminum compound. Preferably, both the aluminum compound and the phosphorus-nitrogen base are soluble in the initiator in the proportions at which polymerization is started.

[0070] In an alternative embodiment, the aluminum compound and / or the phosphorus-nitrogen base are provided as a solution in a suitable solvent.

[0071] The alkylene oxide can be, for example, ethylene oxide, 1,2-propylene oxide, oxetane, 1,2-butylene oxide, 2-methyl-1,2-butylene oxide, 2,3-butylene oxide, tetrahydrofuran, epichlorohydrin, hexyl oxide, octane oxide, styrene oxide, divinylbenzene dioxide, glycidyl ethers (such as bisphenol A diglycidyl ether), epichlorohydrin or other polymerizable oxiranes. In some embodiments, the alkylene oxide is 1,2-propylene oxide, ethylene oxide, or a mixture of at least 50 wt % (preferably at least 80 wt %) of propylene oxide and a corresponding maximum of 50 wt % (preferably maximum of 20 wt %) of ethylene oxide. In some embodiments, two or more alkylene oxides are polymerized simultaneously (to form a random copolymer), and or the combination of alkylene oxides is changed once or more, or even continuously, throughout the polymerization process to form block copolymers and / or random / block copolymers.

[0072] In a specific embodiment, the initiator is poly(propylene oxide), or a random propylene oxide / ethylene oxide copolymer comprising at least 50% by weight or at least 70% by weight of oxypropylene units and up to 50% by weight or up to 30% by weight of ethylene oxide units, and the alkylene oxide is ethylene oxide. In such embodiments, the hydroxyl equivalent of the initiator can be, for example, 500 g / equivalent to 3000 g / equivalent, 500 g / equivalent to 2500 g / equivalent, or 500 g / equivalent to 1750 g / equivalent. In such embodiments, the initiator can be produced in the presence of an aluminum compound and a phosphorus-nitrogen base according to the present invention, and the ethoxylation of the initiator can be carried out with and / or without further addition of an aluminum compound and a phosphorus-nitrogen base, i.e., in the presence of the same aluminum compound and phosphorus-nitrogen base used for alkoxylation before the final ethoxylation step begins, and in the absence of any neutralization, catalyst removal, or catalyst deactivation step after the initiator is produced and before the ethoxylation step.

[0073] The polymerization is carried out by mixing an initiator, an aluminum compound and a phosphorus-nitrogen base with an alkylene oxide and optional comonomers and subsequently polymerizing the alkylene oxide. It is often convenient to mix at least a portion of the initiator with at least a portion of the aluminum compound and at least a portion of the phosphorus-nitrogen base before contacting the aluminum compound and the phosphorus-nitrogen base with the alkylene oxide. The polymerization is carried out at a temperature in the range of -100°C to 250°C or higher. In some embodiments, the reaction temperature is at least 80°C, at least 100°C, at least 120°C or at least 130°C. The polymerization temperature is preferably not more than 190°C, and more preferably not more than 180°C. The polymerization reaction is usually carried out under superatmospheric pressure, but can also be carried out at atmospheric pressure or even below atmospheric pressure.

[0074] Sufficient aluminum compound can be used to provide a commercially reasonable polymerization rate, but it is generally desirable to use as little aluminum compound as possible consistent with a reasonable polymerization rate because this reduces the cost of the catalyst and eliminates the need to remove catalyst residues from the product. The amount of aluminum compound can be, for example, sufficient to provide 10 ppm to 10,000 ppm of aluminum based on the weight of the polymerized alkylene oxide polymer or copolymer product. In specific embodiments, the amount of aluminum compound can be sufficient to provide at least 25 ppm, at least 50 ppm, at least 100 ppm, or at least 250 ppm of aluminum on the aforementioned basis, and can also be sufficient to provide up to 5,000 ppm, up to 2,500 ppm, up to 1500 ppm, or up to 1000 ppm of aluminum on the aforementioned basis.

[0075] The amount of aluminum compound can be sufficient to provide, for example, at least 0.00005 moles of aluminum, at least 0.00075 moles of aluminum, or at least 0.0001 moles of aluminum per equivalent of initiator, and can, for example, be sufficient to provide at most 0.10 moles of aluminum, at most 0.075 moles of aluminum, at most 0.06 moles of aluminum, at most 0.05 moles of aluminum, or at most 0.025 moles of aluminum per equivalent of initiator.

[0076] The amount of phosphorus-nitrogen base can be, for example, at least 0.00005 moles, at least 0.0001 moles, or at least 0.0002 moles per equivalent of initiator, and can be, for example, at most 0.10 moles, at most 0.075 moles, at most 0.06 moles, at most 0.05 moles, at most 0.025 moles, or at most 0.01 moles per equivalent of initiator.

[0077] The molar ratio of the aluminum compound to the phosphorus-nitrogen base can be, for example, from 1:10 to 20:1. Preferred ratios are at least 1:3, at least 1:2, or at least 2:3, and at most 6:1, at most 5:1, at most 4:1, at most 3:1, at most 2.5:1, at most 2:1, at most 3:2, at most 4:3, or at most 1:1. The optimal ratio may vary in a specific aluminum compound / phosphorus-nitrogen base pairing.

[0078] The polymerization reaction can be carried out batchwise, semi-continuously (including continuous addition of initiator as described in US 5,777,177), or continuously.

[0079] In batch polymerization, the aluminum compound, phosphorus-nitrogen base, initiator, alkylene oxide and optional comonomer are mixed to form a reaction mixture, and the reaction mixture is heated to the polymerization temperature in a reaction vessel until the desired molecular weight is obtained. A preferred way to carry out batch polymerization is to dissolve the aluminum compound and phosphorus-nitrogen base in the initiator, then mix the resulting solution with the alkylene oxide, and then subject the resulting mixture to polymerization conditions until the desired molecular weight is obtained and / or the alkylene oxide is consumed. The aluminum compound, phosphorus-nitrogen base, or both can be introduced in the form of a solution in an inert solvent (a hydrocarbon such as toluene or hexane).

[0080] In a semi-batch process, the aluminum compound, phosphorus-nitrogen base and initiator are preferably mixed by dissolving the catalyst and phosphorus-nitrogen base into the initiator. If desired, a polyether monool or polyether polyol corresponding to the polymerization product, and / or a polyether of intermediate molecular weight (between the molecular weight of the initiator and the molecular weight of the product) can be mixed with the initiator. If necessary, the contents of the container are heated to the polymerization temperature, and a portion of the alkylene oxide is introduced into the reaction vessel. When polymerization begins (usually as indicated by a drop in the internal reactor pressure), more alkylene oxide is fed to the reactor under polymerization conditions. The feeding of alkylene oxide is continued until enough alkylene oxide is consumed to reach the target product molecular weight. During the addition of alkylene oxide, additional aluminum compounds and / or phosphorus-nitrogen bases may be added. In a semi-batch process, the entire amount of initiator is usually added at the beginning of the process. After the alkylene oxide feed is completed, the reaction mixture may be boiled at the polymerization temperature to consume any remaining alkylene oxide.

[0081] Continuous polymerization includes adding at least alkylene oxide and initiator continuously or intermittently during polymerization, and removing product continuously or intermittently. Continuous process is usually carried out by establishing steady-state concentrations of aluminum compound (or its reaction product), phosphorus-nitrogen base, initiator (or its reaction product), alkylene oxide and polymer under polymerization conditions (within the operating capacity of the polymerization equipment) in a continuous reactor (such as a loop reactor, a plug flow reactor or a continuous stirred tank reactor). "Polymer" is a mixture of polyethers with a molecular weight greater than the molecular weight of the initiator and up to the expected product molecular weight. Then, as the polymerization proceeds, additional aluminum compound, phosphorus-nitrogen base, initiator and alkylene oxide are continuously added to the reactor. These can be added as a single stream, as separate components or in various sub-combinations, but aluminum compound and phosphorus-nitrogen base are preferably added in the form of a solution in the initiator. During polymerization, the product stream is continuously or intermittently removed from the reactor. The rate of the additional stream and product stream is selected to maintain steady-state conditions in the reactor (within the operating capacity of the equipment) and produce a product with the desired molecular weight.

[0082] The product stream withdrawn from the continuous reactor may be cooked down for a period of time to allow the unreacted alkylene oxide in the product stream to be consumed to low levels.

[0083] The continuous process is particularly suitable for producing polyether products having a hydroxyl equivalent weight of 150 g / equivalent to 5000 g / equivalent, especially 350 g / equivalent to 2500 g / equivalent and even more preferably 500 g / equivalent to 2000 g / equivalent.

[0084] In a semi-batch or continuous process as described above, alkylene oxide may be fed to the reactor as needed by continuously pressurizing the reactor with alkylene oxide to a predetermined internal reactor pressure and / or alkylene oxide partial pressure.

[0085] The polymerization reaction can be carried out in any type of vessel suitable for the pressures and temperatures encountered. In a continuous or semi-continuous process, the vessel may have one or more inlets through which the alkylene oxide and the additional starter compound can be introduced during the reaction. In a continuous process, the reactor vessel should contain at least one outlet through which a portion of the partial polymerization reaction mixture can be withdrawn. Tubular reactors, loop reactors and continuous stirred tank reactors (CTSR) with multiple points for injection of starting materials are suitable types of vessels for continuous or semi-continuous operation. The reactor should be equipped with means for supplying and / or removing heat, whereby the temperature of the reaction mixture can be maintained within the desired range. Suitable means include various types of jacketing for hot fluids, various types of internal or external heaters, etc. The cooking step of the continuously withdrawn product is conveniently carried out in a reactor that prevents significant backmixing from occurring. Pipe or plug flow operation in a tubular reactor is a preferred way to carry out this cooking step.

[0086] The crude product obtained in any of the foregoing processes may contain: up to 0.5% by weight of unreacted alkylene oxide, based on the total weight; small amounts of initiator compounds and their low molecular weight alkoxylates; and small amounts of other organic impurities and water. Volatile impurities (including unreacted alkylene oxide) should be flashed or stripped from the product. The crude product typically contains catalyst residues and residues of aluminum compounds and / or phosphorus-nitrogen bases. These residues are typically left in the product, but can be removed if desired. Water and volatiles can be removed by stripping the polyol.

[0087] The process of the present invention can be used to prepare polyether polyol products having hydroxyl equivalent weights ranging from as low as about 85 to as high as 6,000 or more.

[0088] The polymerization reaction can be characterized by a "build ratio", which is defined as the ratio of the number average molecular weight of the polyether product to the number average molecular weight of the initiator compound. The build ratio can be as high as 160, but is more typically in the range of 2.5 to about 65, and still more typically in the range of 2.5 to about 50. When the hydroxyl equivalent weight of the polyether product is 85 g / equivalent to 400 g / equivalent, the build ratio is typically in the range of about 2.5 to about 15 or about 7 to about 11.

[0089] In some embodiments, alkylene oxide is polymerized with one or more copolymerizable monomers that are not ethylene oxide or is polymerized in the presence of it. Examples of such copolymerizable monomers include carbonate precursors that copolymerize with alkylene oxide to produce carbonate bonds in the product. Examples of such carbonate precursors include carbon dioxide, phosgene, linear carbonates and cyclic carbonates. Other copolymerizable monomers include carboxylic anhydrides that copolymerize with alkylene oxide to produce ester bonds in the product.

[0090] In some embodiments, the polyether polyol prepared according to the present invention is a homopolymer or a random copolymer of propylene oxide, the random copolymer comprising at least 50 weight percent, at least 70 weight percent, or at least 90 weight percent of oxypropylene units formed by polymerization of propylene oxide, and correspondingly up to 50 weight percent, up to 30 weight percent, or up to 10 weight percent of oxyethylene units formed by polymerization of a mixture of propylene oxide and ethylene oxide (in each case in the absence of non-alkylene oxide copolymerizable monomers), the polyether polyol having any one or more of the following characteristics:

[0091] a) a hydroxyl equivalent weight of at least 500 g / equivalent, at least 750 g / equivalent, at least 1000 g / equivalent, or at least 1200 g / equivalent, and at most 4000 g / equivalent, at most 3000 g / equivalent, at most 2500 g / equivalent, at most 2200 g / equivalent, or at most 2000 g / equivalent;

[0092] b) a nominal hydroxyl functionality of 2 to 8;

[0093] c) The terminal unsaturation does not exceed 0.015 meq / g, does not exceed 0.01 meq / g, and does not exceed 0.007 meq / g;

[0094] d) Polydispersity (M) determined by gel permeation chromatography w / M n ) is not more than 1.15, not more than 1.10, not more than 1.07 or not more than 1.05;

[0095] e) contains no more than 2000 parts per million (ppm), no more than 1200 ppm, no more than 1000 ppm, no more than 750 ppm, no more than 500 ppm, no more than 250 ppm, no more than 100 ppm, or no more than 50 ppm of a moiety having a molecular weight of 40,000 g / mol or greater as determined by GPC, based on the weight of the polyether polyol; and

[0096] f) no more than 12%, no more than 10%, no more than 8%, no more than 6%, or no more than 5% of the hydroxyl groups are primary hydroxyl groups as determined by ASTM D-4273 or equivalent. The polyether product can have all of features a) to f).

[0097] In a specific embodiment, the polyether polyol is a propylene oxide homopolymer or a random copolymer of a mixture of at least 85 weight percent propylene oxide and correspondingly up to 15 weight percent ethylene oxide, based on the total weight of all alkylene oxides, in each case prepared by polymerizing propylene oxide or a mixture of propylene oxide and ethylene oxide in the absence of a copolymerizable monomer of ethylene oxide; and the polyether polyol is characterized by: a) a hydroxyl equivalent weight of 1000 g / equivalent to 2500 g / equivalent, b) a nominal functionality of 2 to 8; c) a terminal unsaturation of not more than 0.007 meq / g; d) a polydispersity (M w / M n ) is not more than 1.07, and preferably not more than 1.05; and e) contains not more than 1200 ppm, not more than 1000 ppm, not more than 250 ppm, or not more than 50 ppm of a moiety having a molecular weight of 40,000 g / mol or more as determined by GPC. Such polyether polyols may additionally have not more than 12%, not more than 10%, not more than 8%, not more than 6%, or not more than 5% primary hydroxyl groups.

[0098] The polyether polyols produced according to the present invention can be used to prepare polyurethanes, etc. The polyether polyol products of higher equivalent weight (500 g / equivalent to 6000 g / equivalent) can be used to prepare elastomeric polyurethanes or semi-elastomeric polyurethanes (including non-porous or microporous elastomers) and soft polyurethane foams. Polyurethane foams can be made in sheet or molding processes. Polyether polyol products with equivalent weights of about 225 to 400 can be used to make semi-soft foams and so-called viscoelastic foams or "memory" foams. Polyether polyols with equivalent weights of 85 to 400 can be used to prepare rigid polyurethane foams (such as insulation foams for electrical appliances, buildings, hulls, etc.) and various coatings, adhesives, sealants and elastomeric products. The properties of the polyether polyols are often quite similar to those of polyether polyols prepared in conventional DMC catalytic polymerization processes and alkali metal hydroxide catalyzed polymerization processes.

[0099] The polyether monool produced according to the present invention can be used as a surfactant or an industrial solvent, etc.

[0100] The following examples are provided to illustrate the present invention but are not intended to limit the scope of the present invention. Unless otherwise indicated, all parts and percentages are by weight.

[0101] Catalyst preparation procedure

[0102] The initiator is heated at 70°C and purged with nitrogen, and / or passed through an alumina plug before use. 20 g of the initiator is transferred to a 50 mL glass jar. Under nitrogen, the specified amount of aluminum compound and phosphorus-nitrogen base (if any) are mixed with the initiator. The jar is capped and its contents are stirred for about 20 minutes. If the resulting mixture appears uneven, the contents of the jar are heated again at 70°C with continued stirring for 5 to 10 minutes, then cooled.

[0103] Parallel Pressure Reactor (PPR) Polymerization Procedure

[0104] A 48-well Symyx Technologies parallel pressure reactor (PPR) was used for alkylene oxide polymerization and / or propylene oxide / carbon dioxide copolymerization. Each of the 48 wells was equipped with an individually weighed glass insert with an internal working liquid volume of approximately 5 mL. Each of the wells contained an overhead paddle stirrer.

[0105] 0.7 mL of the initiator / catalyst / phosphorus-nitrogen base mixture (about 0.72 g of initiator) was added to each insert. Each well was pressurized with 50 psig (344.7 kPa) of nitrogen and then heated to the polymerization temperature. When the polymerization temperature was reached, 1 mL of epoxide was injected into each well, where it reacted with the initiator in the glass insert.

[0106] The internal pressure in the headspace of each well was monitored individually throughout the polymerization process. After the first injection of epoxide, the internal pressure was observed every hour, and if the pressure in any particular well had dropped below 190 psig (1.31 MPa), an additional 1 mL of alkylene oxide was injected. This step was repeated up to three times during the entire run (i.e., within 4 hours). Four hours after the first injection of epoxide, the wells were cooled to room temperature and vented. The glass inserts were allowed to stand overnight at 40° C. to 50° C. under nitrogen to allow the residual epoxide to volatilize, after which the inserts were weighed to determine the amount of product.

[0107] The molecular weight and polydispersity (M) of the obtained products were analyzed by gel permeation chromatography against polystyrene standards. w / M n ). The product is functionalized with trifluoroacetic anhydride according to standard methods such as ASTM D-4273 and by 19 The resulting products were evaluated by F NMR spectroscopy to determine the primary hydroxyl content.

[0108] Examples 1 to 7 and Comparative Sample A

[0109] Propoxylation of a 700 molecular weight trifunctional poly(propylene oxide) initiator was carried out in a semi-batch reactor using various aluminum compounds and bis(triphenylphosphinoalkylene (ammonium) chloride salt (PPNCl)) as the phosphorus-nitrogen base. The polymerization temperature was 160°C.

[0110] The aluminum compounds are triethylaluminum (AlEt3), diethylaluminum chloride (Et2AlCl), diisobutylaluminum hydride (DIBAL) and tetraethyldialuminoxane (TEDA), as shown in Table 1.

[0111] In each of Examples 1, 2, and 5 to 7, the molar ratio of aluminum compound:PPNCl was 1:0.5; for Examples 3 and 4, the ratio was 1:1. The molar ratio of PPNCl to aluminum provided by the aluminum compound is shown in Table 1. PPNCl was omitted in Comparative Sample A.

[0112] Table 1 shows the amount of 1,2-propylene oxide (PO) feed, run time and output, as well as the primary hydroxyl percentage %, polydispersity and M of the product. n .

[0113]

[0114] Comparative Sample A is a control sample in which TEDA itself is the aluminum catalyst; no phosphorus-nitrogen base is present. Polymerization proceeds slowly. Very little PO is consumed after almost 20 hours, and the yield of the product is correspondingly low, as is the molecular weight of the product.

[0115] In each of Examples 1 to 7, an aluminum compound was paired with PPNCl. In each case, approximately 5 times more PO was consumed than in Comparative Sample A, and therefore the yield and product molecular weight were higher. The runs using triethylaluminum and TEDA were particularly significant, as the run times were an order of magnitude shorter than the control. These combinations of aluminum compounds and PPNCl are particularly active polymerization catalysts.

[0116] In all cases the polydispersity was low and the % of primary hydroxyl groups was also very low in those cases measured.

[0117] Examples 8 to 26 and Comparative Sample B

[0118] The polymerization of propylene oxide was carried out using the PPR procedure described above. The initiator was the triol with a molecular weight of 700 as described in the previous examples. The aluminum compound and the amount of the aluminum compound in each case (by weight, parts per million by weight, based on the amount of initiator, ppm) are shown in Table 2. In all cases, the phosphorus-nitrogen base was PPNCl. The initial molar ratio of the aluminum compound to the phosphorus-nitrogen base is shown in Table 2. The polymerization temperature was 160°C. The amount of product produced, the % of primary hydroxyl groups, the number average molecular weight and the polydispersity (PDI, M w / M n ) as reported in Table 2.

[0119] Table 2 - PO polymerization using various Al compounds and PPNCl

[0120]

[0121]

[0122] *Comparative Example. ND = Not Determined. 1 Ethyl aluminum chloride 2 Diisobutylaluminum chloride. 3 Triethylaluminum. 4 Tetramethylalanine. 5 Tris(diisopropoxyaluminum) phosphate.

[0123] As shown in the data of Examples 8, 12, 16, 20-22, and 25, a 2:1 or greater excess of PPNCl resulted in little polymerization under these conditions. When used in such an excess, PPNCl may actually inhibit polymerization, as indicated by comparing combination Sample B and Example 25. Higher yields and higher molecular weights were obtained when the molar ratio of Al compound to PPNCl was from 1:1 to 2:1. The results of Examples 20-24 indicate that, at least for the TEDA / PPNCl combination, the molar ratio should be kept below 4:1.

[0124] Example 27 to Example 31

[0125] EO polymerizations were carried out using the PPR procedure described above. The initiator was the triol having a molecular weight of 700 as described in the previous examples. The aluminum catalyst is shown in Table 3 below. The amount of aluminum compound in each case is shown in Table 3; the amount is in ppm based on the weight of the initiator. The phosphorus-nitrogen base was PPNCl. The aluminum compound and the phosphorus-nitrogen base were initially present in a molar ratio of 1:1 in Examples 27 to 29; 1:0.5 in Example 30, and 1:0.25 in Example 31. The polymerization temperature was 160°C. The amount of product produced, the % of primary hydroxyl groups, the number average molecular weight and the polydispersity (PDI, M w / M n ) as reported in Table 3.

[0126] Table 3 - EO polymerization using PPNCl

[0127]

[0128] *The molar ratio of TEDA / PPNCl is 1:0.5, with 0.25 mol of PPNCl per mol of Al atom.

[0129] **The molar ratio of TEDA / PPNCL is 1:0.25, 0.125 mol of PPNCL per mol of Al atom. ND means not determined.

[0130] In each case rapid polymerization was obtained which produced high molecular weight, low polydispersity polymers.

[0131] Example 32 to Example 36

[0132] Various combinations of various aluminum compounds and PPNCl were evaluated in the propoxylation of small molecule initiators. In all cases, the molar ratio of PPNCl to aluminum provided by the aluminum compound was 1:1. As shown in Table 4, the initiators were o-toluenediamine (oTDA), bis(3-aminopropyl)methylamine (BAPMA), glycerol and sorbitol. The polymerization was carried out in the same conventional manner as in the previous examples using the PPR procedure. The aluminum compounds are shown in Table 4, and the results of the polymerization are also shown in the table.

[0133] Table 4 - Small molecule initiated PO polymerization using PPNCl

[0134]

[0135] The combination of various aluminum compounds with TBD resulted in effective propoxylation of a variety of low molecular weight hydroxyl-containing and amine-containing initiators, as demonstrated by the data in Table 4. As before, the polydispersity remained low.

[0136] Example 37 to Example 45 and Comparative Samples C to E

[0137] In these polymerizations, the initiator was the same 700 molecular weight triol as described in the previous examples, and the alkylene oxide was propylene oxide. The aluminum compound and phosphorus-nitrogen base are as shown in Table 5.

[0138] In Table 5, "PAZ-P1" represents tert-butylimino-tris(dimethylamino)phosphorane, and "HMPA" represents hexamethylphosphoramide (i.e., tris(dimethylaminophosphine oxide)). "DCI16302" and "DCI16303" have corresponding structures:

[0139]

[0140] PPNF, PPNOAc and PPNPF6 are fluorine, acetate and PF6 bis(triphenylphosphite)ammonium salt, respectively.

[0141] The amount of catalyst in each case was 2000 ppm, based on the initiator. The phosphorus-nitrogen base (if present) and the aluminum compound were initially present in a molar ratio of 1:1, which also resulted in a molar ratio of PPNCl to aluminum of 1:1. The polymerization temperature was 160° C. The amount of the product produced, the % of primary hydroxyl groups, the number average molecular weight and the polydispersity (PDI, M w / M n ) as shown in Table 5.

[0142] Table 5

[0143]

[0144]

[0145] PAZ-P1 showed a strong enhancement when used in combination with Et2AlCl or EtAlCl2 catalysts. HMPA, DCI16302, and DCI16303 all showed a moderate enhancement when used with DIBAL catalyst. Fluoride, acetate, and hexafluorophosphate bis(triphenylphosphine alkylene (ammonium)) salts all showed significant enhancement.

Claims

1. A method for producing an alkylene oxide polymer or copolymer, the method comprising: The invention relates to a method for preparing an alkylene oxide polymer or copolymer comprising combining (i) at least one aluminum compound containing at least one trisubstituted aluminum atom, wherein at least one of the substituents of the at least one trisubstituted aluminum atom is a hydrocarbon group, (ii) at least one initiator, (iii) at least one alkylene oxide, (iv) from 0.00005 mol to 0.1 mol of at least one phosphorus-nitrogen base per equivalent of initiator, and optionally (v) at least one comonomer that is not ethylene oxide, and polymerizing the alkylene oxide or copolymerizing the alkylene oxide with the comonomer to form the alkylene oxide polymer or copolymer, wherein the phosphorus-nitrogen base is one or more of the following: fluoride, chloride, bromide, iodide, acetate, triflate, BF4 of bis(triphenylphosphinoalkyl)ammonium - or PF6 - salts; hexamethylphosphoramide (tris(dimethylaminophosphine oxide), hexaethylphosphoramide, hexa-tert-butylphosphoramide and tris(N,N-tetramethylene)phosphoramide, 1,1,1,3,3,3-hexa(dimethylamino)diphosphazene fluoride, 1,1,1,3,3,3-hexa(dimethylamino)diphosphazene chloride, 1,1,1,3,3,3-hexa(dimethylamino)diphosphazene bromide, tetrakis[tris(dimethylamino)phosphoranilin]phosphonium fluoride, tetrakis[tris(dimethylamino)phosphoranilin]phosphonium chloride and tetrakis[tris(dimethylamino)phosphoranilin]phosphonium bromide.

2. The method according to claim 1, wherein the aluminum atom of the aluminum compound is substituted by one or two hydrocarbon groups and by one or two halogen, oxo, ether, hydride or phosphonate groups.

3. The method of claim 1, wherein the aluminum compound comprises one or more of the following: trimethylaluminum, triethylaluminum, triisopropylaluminum, tri-n-propylaluminum, triisobutylaluminum, tri-n-butylaluminum, tri-tert-butylaluminum, and trioctadecylaluminum.

4. The method of claim 1, wherein the aluminum compound comprises one or more of the following: dimethylaluminum chloride, methylaluminum dichloride, diethylaluminum chloride, ethylaluminum dichloride, diisobutylaluminum chloride, isobutylaluminum dichloride, bis[(2,6-di-tert-butyl-4-methyl)phenoxy]methylaluminum, 2,6-di-tert-butyl-4-methylphenoxydimethylaluminum, bis(2,6-diisopropyl)phenoxymethylaluminum, (2,6-diisopropyl)phenoxydimethylaluminum, bis[(2,6-diphenyl)phenoxy]methylaluminum, (2,6-diphenyl)phenoxydimethylaluminum, bis[(2,4,6-trimethyl)phenoxy]methylaluminum, (2,4,6-trimethyl)phenoxydimethylaluminum Aluminum, tetraethylaluminum, tetramethylaluminum, diisobutylaluminum hydride, isobutylaluminum dihydride, dimethylaluminum hydride, methylaluminum dihydride, diethylaluminum hydride, ethylaluminum dihydride, diisopropylaluminum hydride, isopropylaluminum dihydride, diethylaluminum ethoxide, ethyldiethoxidealuminum, dimethylaluminum ethoxide, methyldiethoxidealuminum, dimethylaluminum fluoride, methylaluminum difluoride, diethylaluminum fluoride, ethylaluminum difluoride, diisobutylaluminum fluoride, isobutylaluminum difluoride, dimethylaluminum bromide, methylaluminum dibromide, diethylaluminum bromide, ethylaluminum dibromide, diisobutylaluminum bromide, isobutylaluminum dibromide, dimethylaluminum iodide, methylaluminum diiodide, diethylaluminum iodide, ethylaluminum diiodide, diisobutylaluminum iodide, and isobutylaluminum iodide.

5. The method of claim 1, wherein the aluminum compound comprises one or more of bis(dimethylaluminum)methylphosphonate, bis(diethylaluminum)methylphosphonate, bis(diethoxyaluminum)methylphosphonate, bis(di-n-propylaluminum)methylphosphonate, bis(diisopropylaluminum)methylphosphonate, bis(di-n-propoxyaluminum)methylphosphonate, bis(diisopropoxyaluminum)methylphosphonate, bis(di-tert-butylaluminum)methylphosphonate, bis(di-tert-butoxyaluminum)methylphosphonate, bis(diphenylaluminum)methylphosphonate, bis(diphenoxyaluminum)methylphosphonate, bis(diisobutylaluminum)methylphosphonate, and tetraalkylaluminoxanes, wherein each alkyl group independently contains 1 to 6 carbon atoms.

6. The method of any one of the preceding claims, wherein the aluminum compound is present in an amount sufficient to provide 100 to 2,500 parts by weight of aluminum per million parts by weight of the alkylene oxide polymer or copolymer.

7. The process of any one of claims 1 to 5, wherein the aluminum compound and the initiator are combined in a ratio to provide 0.00005 mole to 0.05 mole of aluminum per equivalent of the initiator.

8. The process according to any one of claims 1 to 5, wherein the molar ratio of the aluminum compound to the phosphorus-nitrogen base is at least 1:3 and at most 5:

1.

9. The method according to any one of claims 1 to 5, wherein the initiator comprises one or more hydroxyl groups and has a hydroxyl equivalent weight of 30 g / equivalent to 6000 g / equivalent.

10. The method according to any one of claims 1 to 5, wherein the initiator comprises 2 to 8 hydroxyl groups and has an equivalent weight of 30 g / equivalent to 250 g / equivalent.

11. The method according to any one of claims 1 to 5, wherein the alkylene oxide is propylene oxide, ethylene oxide, or a mixture of propylene oxide and ethylene oxide.

12. The process according to any one of claims 1 to 5, wherein the initiator is a homopolymer of propylene oxide and / or a random or block copolymer of propylene oxide having a hydroxyl equivalent weight of at least 125 g / equivalent and at most 4000 g / equivalent, and wherein no more than 25% of the hydroxyl groups are primary hydroxyl groups.

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