HK1064395B - Activated starter mixtures and the processes related thereto - Google Patents

Description

Active starter mixtures and related methods

Technical Field

The present invention relates to a reactive starter mixture which can be used for preparing polyoxyalkylene polyols. The invention also relates to a process for preparing a reactive starter mixture, in particular a reactive starter mixture comprising low molecular weight starter compounds. The invention also relates to a batch or semi-batch process for the polyaddition of alkylene oxides onto reactive starter mixtures, in particular onto a reactive starter mixture comprising low molecular weight starter compounds.

Background

Base catalyzed oxyalkylation processes have been used for many years to prepare polyoxyalkylene polyols. In the base-catalyzed alkoxylation process, a suitable low molecular weight starter compound, such as propylene glycol or glycerol, is alkoxylated with an alkylene oxide, such as ethylene oxide or propylene oxide, to form a polyoxyalkylene polyol. The reactor capacity can be effectively utilized in the base-catalyzed alkoxylation process because the build (build) ratio (weight of polyol/weight of starter) is relatively high as a result of the use of low molecular weight starter compounds in the alkoxylation process.

However, to some extent, basic catalysts catalyze the isomerization of propylene oxide to form allyl alcohol. In the polymerization of propylene oxide, allyl alcohol acts as a monofunctional initiator. Thus, when a basic catalyst, such as potassium hydroxide, is used to catalyze the polymerization of propylene oxide, the product contains allyl alcohol-initiated monofunctional impurities. Isomerization reactions become more prevalent as the molecular weight of the polymerized product increases. Thus, poly (propylene oxide) products prepared using KOH as a catalyst and having an equivalent weight of 800 or greater tend to contain significant amounts of monofunctional impurities. This tends to cause a decrease in the average functionality of the product and a broadening of the molecular weight distribution. In general, the physical properties of polyurethane products made with polyols having higher average functionalities are generally better.

Double metal cyanide ("DMC") catalysts can be used to prepare polyols having lower unsaturation and narrower molecular weight distributions than polyols prepared using KOH catalysis. DMC catalysts are useful in the manufacture of polyether, polyester, and polyetherester polyols that are very useful in polyurethane coatings, elastomers, sealants, foams, and adhesives.

DMC catalysts are generally obtained by reacting an aqueous solution of a metal salt (e.g., zinc chloride) with an aqueous solution of a metal cyanide (e.g., potassium hexacyanocobaltate) in the presence of an organic ligand. The preparation of typical DMC catalysts is described, for example, in U.S. Pat. nos.3,427,256, 3,289,505 and 5,158,922.

In the preparation of DMC catalysts, the presence of organic ligands is required in order to obtain satisfactory catalytic activity. Although water-soluble ethers (e.g., dimethoxyethane ("glyme") or diglyme) and alcohols (e.g., isopropanol or tert-butanol) are typically used as organic ligands, other common classes of compounds are also described as organic ligands. For example, U.S. Pat. Nos. 4,477,589, 3,829,505 and 3,278,459 disclose DMC catalysts containing organic ligands selected from alcohols, aldehydes, ketones, ethers, esters, amides, nitriles, and sulfides.

DMC catalysts having enhanced activity for epoxide polymerization are known. For example, U.S. Pat. Nos. 5,482,908 and 5,545,601 disclose DMC catalysts having enhanced activity, which comprise a functionalized polymer such as a polyether.

However, in the presence of DMC catalysts, the alkoxylation reaction initiated by conventional low molecular weight starter compounds (such as water, propylene glycol, glycerol and trimethylolpropane) is very slow (if at all possible), especially when polyols are prepared in a typical batch process. Long catalyst initiation times can increase reaction cycle times and lead to DMC catalyst deactivation. Thus, in a typical batch or semi-batch process, high molecular weight starting compounds are generally used.

High molecular weight starter compounds for DMC-catalyzed oxyalkylation processes are generally prepared by oxyalkylating a low molecular weight starter compound, such as glycerol, in the presence of a basic catalyst, such as KOH, to produce a few hundred molecular weight oxyalkylated polyol starters, which are purified of KOH residues, and then oxyalkylated in the presence of DMC catalysts to produce several thousand molecular weight polyether polyols. Before the starter compound can be used as an initiator in a DMC-catalyzed alkoxylation process, the base catalyst in the starter compound must be removed, since even minute amounts of basic substances often deactivate the DMC catalyst.

A process for preparing polyether polyols using DMC catalysts is described, for example, in U.S. patent No.6,359,101, which eliminates the need to synthesize expensive high molecular weight starter compounds in a separate dedicated reactor using KOH catalysts. However, this process described in this U.S. Pat. No.6,359,101 is limited to the activation of specific low molecular weight starter compounds in the presence of DMC catalysts under specific reaction conditions.

Another method for preparing polyether polyols using DMC catalysts is described, for example, in U.S. patent No.5,767,323, which eliminates the need for synthesizing expensive high molecular weight starter compounds with KOH catalysts. This patent describes the use of a pre-initiated initiator/alkylene oxide/catalyst masterbatch with a shortened induction period. This patent discloses adding one or more initiators and catalysts having an equivalent weight of from 100Da to 500Da to a reactorN₂After flushing, an initial amount of alkylene oxide is added until a pressure drop occurs. The alkylene oxide is preferably added to the reactive starting mixture, but the reactive starting mixture may optionally be further mixed with additional starting compounds, in particular a compound of the same molecular weight or of a higher molecular weight. At this point, the alkoxylation reaction can also begin without a significant induction period.

In a typical batch or semi-batch process for producing DMC-catalyzed polyols, the high molecular weight starter compound and the DMC catalyst are charged all at once to the reactor. One disadvantage of charging the starting compound into the reactor at once is the inefficient use of the reactor capacity. For example, the preparation of a 3000Da molecular weight polypropoxylated glycerol may be achieved by propoxylating a 1500Da molecular weight oligomeric propoxylated glycerol starting material until a molecular weight of 3000Da is reached. The build ratio was 3000Da/1500Da or 2.0. This build ratio does not make efficient use of the reactor capacity since about 40% of the total reactor capacity is used only for the starting compounds.

U.S. Pat. No.5,689,012 describes a process for preparing DMC-catalyzed polyols which efficiently utilizes reactor capacity while efficiently utilizing low molecular weight starter compounds. However, the process described in this patent involves continuously adding the low molecular weight starting compound to the reactor rather than charging the high molecular weight starting compound into the reactor all at once (as in a batch or semi-batch process).

U.S. Pat. No.5,777,177 also describes a process for preparing DMC-catalyzed polyols that efficiently utilizes reactor capacity while efficiently utilizing low molecular weight starter compounds. This process, disclosed in U.S. Pat. No.5,777,177, describes a process for preparing DMC-catalyzed polyols by continuously feeding propylene oxide and a low molecular weight starter compound (e.g., water, propylene glycol, glycerol, or trimethylolpropane) into a reactor, and additionally adding propylene oxide and a catalyst after the polymerization has been initiated with a high molecular weight starter compound.

However, the process described in U.S. Pat. No.5,777,177 requires that a low concentration of low molecular weight starter compound be maintained in the reactor at all times, so that the low molecular weight starter compound is consumed at the same rate as it is fed into the reactor. There is therefore still a need for an improved batch or semi-batch process for the polyaddition of alkylene oxides onto a reactive starter mixture, in particular onto a reactive starter mixture composed of low molecular weight starter compounds.

Disclosure of Invention

The present invention relates to a reactive starter mixture for the preparation of polyoxyalkylene polyols. The invention also relates to a process for preparing a reactive starter mixture, in particular a reactive starter mixture comprising low molecular weight starter compounds. The invention also relates to a batch or semi-batch process for the polyaddition of alkylene oxides onto a reactive starting mixture, in particular onto a reactive starting mixture comprising a low molecular weight starting compound.

Detailed description of the preferred embodiments

The present invention relates to an active starter mixture comprising a) at least one preactivated starter compound comprising i) at least one first starter compound having an equivalent weight of at least 70; ii) at least one epoxide; and iii) at least one DMC catalyst (hereinafter referred to simply as a "masterbatch"); and b) at least 2 mol% of at least one second starting compound having an equivalent weight which is smaller than that of the first starting compound.

The invention also relates to a process for the preparation of an active starting mixture, which process involves mixing a) at least one masterbatch; and b) at least 2 mol% of at least one second starting compound having an equivalent weight which is smaller than that of the first starting compound.

The invention also relates to a batch or semi-batch process for polyaddition of alkylene oxides onto reactive starting mixtures, which process involves reacting 1.) at least one reactive starting mixture comprising a mixture of at least one masterbatch and at least 2 mol% of at least one second starting compound having an equivalent weight which is less than that of the first starting compound; and 2.) at least one epoxide.

Any hydroxy functional starter known in the art having an equivalent weight of at least 70 can be used as the first starting compound. The first starting compounds of the present invention have an equivalent weight of at least 70, preferably at least 150, more preferably at least 250, and an average hydroxyl functionality in the range of from about 1 to about 8.

The first starting compounds of the present invention can be prepared by any method known in the art, for example, by base catalysis or by DMC-catalysis. The DMC-catalyzed first starter compounds used in the present invention are those prepared, for example, by reacting a heterocyclic monomer (usually an epoxide) with an active hydrogen-containing initiator (typically a low molecular weight polyol) in the presence of a DMC catalyst. See, for example, U.S. Pat. No.5,689,012. Base-catalyzed first starting compounds useful in the present invention are those prepared, for example, by reacting a heterocyclic monomer (usually an epoxide) with an active hydrogen-containing initiator (typically a low molecular weight polyol) in the presence of KOH.

Examples of first starting compounds useful in the present invention include, for example, polyoxypropylene polyols, polyoxyethylene polyols, polytetramethylene ether glycols, propoxylated glycerols, tripropylene glycols, alkoxylated allyl alcohols and mixtures thereof.

Any hydroxy functional starter known in the art with an equivalent weight of at least 70 can be used as the second starting compound. The amount of second starting compound that can be mixed with the masterbatch depends on many factors including, for example, the equivalents of starting material, the catalyst level, the activity of the catalyst, the equivalents of first starting compound used to prepare the masterbatch, and other reaction conditions such as temperature, oxide type, oxide feed rate, and the desired hydroxyl number of the product. In general, the higher the equivalent weight of the second starting compound, the higher the catalyst level and the higher the activity of the catalyst, the greater the amount of second starting compound that can be mixed with the masterbatch.

Examples of second starting compounds useful in the present invention include, for example, water, propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, glycerol, trimethylolpropane, sorbitol, methanol, ethanol, butanol, polyoxypropylene polyol, polyoxyethylene polyol, alkoxylated allyl alcohol, and mixtures thereof. Preferred second starter compounds of the present invention include glycerol, propylene glycol, dipropylene glycol and tripropylene glycol.

Any epoxide known in the art may be used in the present invention. Examples of epoxides useful in the present invention include, for example, ethylene oxide, propylene oxide, butylene oxide, styrene oxide, and mixtures thereof.

DMC catalysts useful in the present invention are well known in the art and are described, for example, in U.S. patent nos.3,278,457, 3,829,505, 3,941,849, 4,472,560, 5,158,922, 5,470,813, and 5,482,908. Preferred DMC catalysts useful in the present invention are disclosed in U.S. patent No.5.482,908, which comprise zinc (III) hexacyanocobaltate, t-butanol and a functionalized polyol.

The methods described herein are suitable for use with different forms of DMC catalysts, including, for example, DMC catalysts in the form of powders, slurries (see, e.g., U.S. Pat. No.5,639,705), and suspensions (see, e.g., U.S. Pat. No.4,472,560).

The master batches of the invention can be prepared by mixing at least one first starter with at least one epoxide in the presence of at least one DMC catalyst. Preferably, the masterbatch of the present invention is prepared by reacting a first starting compound with an epoxide in the presence of a DMC catalyst at a temperature in the range of from about 60 deg.C to about 250 deg.C, preferably from about 80 deg.C to about 180 deg.C, and more preferably from about 90 deg.C to about 140 deg.C.

Sufficient epoxide is added to activate the DMC catalyst. DMC catalyst activation is typically indicated by a pressure drop within the reactor, typically a pressure drop within the range of about 30% to about 50% of the initial reactor pressure. The initial pressure in the reactor is obtained by adding the desired amount of epoxide to the reactor. The completion of DMC catalyst activation is generally indicated by no further decrease in pressure in the reactor (indicating that all of the epoxide has been consumed). The amount of DMC catalyst in the masterbatch is in the range of about 50 to 10,000ppm, preferably from about 50 to 5,000ppm, based on the total amount of the masterbatch.

Preferably, the first starting compound is stripped prior to reacting with the epoxide. The stripping step is generally carried out in the presence of both the first starter compound and the DMC catalyst. The stripping is preferably carried out under vacuum, as disclosed in U.S. Pat. No.5,844,070.

Preferred stripping methods include inert gas sparging in combination with vacuum stripping, wiped film evaporation, vacuum stripping in the presence of organic solvents, and the like. The temperature of the stripping is not critical. Preferably, the temperature of the stripping is in the range of from about 60 ℃ to about 200 ℃, more preferably from about 80 ℃ to about 150 ℃. Stripping is carried out under reduced pressure (less than 760 mm Hg). Preferably, the reactor pressure at stripping is less than about 300 mm Hg, more preferably less than about 200 mm Hg.

Reducing the water content of the first starting compound by stripping can provide faster catalyst activation. Preferably, the water content of the first starting compound is reduced to less than about 100ppm, more preferably to less than about 50 ppm. Other methods known to those skilled in the art may also be used to reduce the water content of the first starting compound.

The masterbatch may be mixed with the second starting compound after storage for a period of time under appropriate storage conditions, or may be mixed with the second starting compound within a relatively short period of time after preparation. The masterbatch may be a "heel" of masterbatch from a previous polyoxyalkylation process.

Preferably, the masterbatch is mixed with at least 2 mole percent, preferably at least about 50 mole percent, more preferably at least about 75 mole percent (based on the total mole percent of the masterbatch) of the second starting compound in a relatively short period of time. Typically, the temperature at which the masterbatch and second starting compound are mixed ranges from about 60 ℃ to about 250 ℃, preferably from about 80 ℃ to about 180 ℃, and more preferably from about 90 ℃ to about 140 ℃.

The masterbatch of the invention is mixed with a second starting compound to form a reactive starting mixture. The reactive starter mixture prepared according to the present invention is particularly useful in the preparation of polyoxyalkylene polyols in a batch or semi-batch process. The reactive starter mixture according to the invention is preferably stripped as described above and then reacted with at least one epoxide to form the polyoxyalkylene polyol. The temperature at which the reactive starting mixture is reacted with the epoxide is generally in the range of from about 20 ℃ to about 200 ℃, preferably from about 40 ℃ to about 180 ℃, and more preferably from about 50 ℃ to about 150 ℃. The reaction may be carried out at a total pressure of from 0.0001 to 20 bar. The polyaddition reaction can be carried out in bulk or in an inert organic solvent such as toluene or tetrahydrofuran ("THF"). The amount of solvent is generally from 0 to 30% by weight based on the total weight of polyoxyalkylene polyol to be prepared.

The number average molecular weight of the polyoxyalkylene polyol prepared by the process of the present invention is generally in the range of from 200 to 100,000 g/mole, preferably from about 1,000 to 50,000 g/mole, more preferably from about 2,000 to 20,000 g/mole.

The polyoxyalkylene polyols prepared by the process of the present invention are very useful for preparing polyurethane foams, elastomers, sealants, coatings and adhesives. The polyoxyalkylene polyols prepared by the process of the present invention also have a lower degree of unsaturation than polyoxyalkylene polyols prepared using basic catalysts.

The polyoxyalkylene polyols generally prepared by the process of the present invention have a value of unsaturation of less than 0.015 meq/g, preferably less than 0.008 meq/g. Preferably, the polyoxyalkylene polyols prepared by the process of the present invention have an unsaturation of about 0.0015 meq/g. The polyoxyalkylene polyols produced by the process of the present invention generally have hydroxyl numbers ranging from about 50 to about 500, preferably from about 200 to about 400, and more preferably from about 200 to about 250 mg KOH/g.

The present invention has several advantages. In a first aspect, the present invention provides a reactive starter mixture, in particular a reactive starter mixture comprising a low molecular weight starter compound, which is capable of rapidly initiating polymerization. (see example 1). In contrast, typical low molecular weight starter compounds, even in the presence of highly active DMC catalysts, initiate the reaction very slowly. (see comparative example 2)

Second, since the low molecular weight starter compound can be activated by the masterbatch of the present invention, the need to synthesize expensive high molecular weight starters in a separate dedicated reactor with KOH catalyst can be eliminated. Third, the polymerization build ratio of the present invention is higher because low molecular weight starter compounds can be used in the present invention. Thus, the process of the present invention efficiently utilizes reactor capacity.

The following examples also demonstrate that the process of the present invention can produce polyols having improved physical properties. Propoxylation of a typical low molecular weight starter compound, as shown in comparative example 2, produces a dark purple polyether polyol. In contrast, the reactive starter mixture of the present invention undergoes propoxylation and the polyether polyol produced carries only a slightly faint pink color. Consumers prefer to purchase polyols that are light colored or colorless at all. In addition, propoxylation of the reactive starter mixture prepared according to the invention leads to a polyether polyol having a low viscosity, a narrow molecular weight distribution and a low degree of unsaturation.

Example 1

Polyether polyols are prepared by propoxylating the starting mixture prepared according to the invention:

a one liter stirred autoclave was charged with polyoxypropylene glycol (400MW) starter (70 g) and a DMC catalyst (0.1673 g), prepared according to U.S. Pat. No.5,482,908, the contents of which are incorporated herein by reference. The mixture was heated to 130 ℃ under vacuum with nitrogen stripping and held for 15 minutes. The reactor was closed with vacuum and sufficient propylene oxide was added to raise the initial pressure to 1379hPa (20psia) (about 12 g). Within about two minutes, an accelerated drop in pressure to less than 50% of the initial pressure was noted, indicating that activation of the DMC catalyst had occurred. After about ten minutes, the pressure drop stopped, indicating that all of the propylene oxide had been consumed, thereby forming a masterbatch. The product in the reactor was cooled to 70 ℃. The masterbatch was then reacted with dipropylene glycol (200 g) to produce an activated starting mixture. The activated starting mixture was then heated to 100 ℃ under vacuum with nitrogen stripping and held for 15 minutes. The reactor was closed with vacuum and heated to 130 c and sufficient propylene oxide was added to raise the initial pressure to 2758hPa (40psia) (about 39 g). The pressure was observed and after about twenty minutes, the pressure accelerated to drop to less than 50% of the initial pressure. Propylene oxide (537 g) was added continuously at a constant rate for about two hours. The reaction was then held at 130 ℃ until the pressure was constant. The product was stripped of residual unreacted monomer at 60 ℃ under vacuum. The product was faintly pink. The polyol synthesized had a hydroxyl number of 264 meq/g, an unsaturation of 0.0015 meq/g, a polydispersity of 1.03, and a viscosity of 87 cps.

Example 2 (comparative example)

Direct propoxylation of dipropylene glycol:

a one liter stirred autoclave was charged with dipropylene glycol (200 g) and 0.149 g of the DMC catalyst used in example 1 (prepared according to U.S. Pat. No.5,482,908). The contents of the autoclave were heated to 100 ℃ under vacuum with nitrogen stripping and held for fifteen minutes. The reactor was closed under vacuum, heated to 130 ℃ and sufficient propylene oxide was added to raise the initial pressure to 1724hPa (25psia) (about 19 g). The reactor pressure was observed and after about thirty-five minutes the pressure dropped to about 70% of the initial value. An additional 10 grams of propylene oxide was added. After thirty minutes, the pressure again dropped to about 70% of the initial value. An additional 19 grams of propylene oxide was added and reacted for thirty minutes. Propylene oxide (386 grams) was added at a rate sufficient to maintain a pressure of about 2413hPa (35 psia). The addition of this oxide took 4.5 hours to complete. The reaction was then held at 130 ℃ until the pressure was constant. The product was stripped of residual unreacted monomer at 60 ℃ under vacuum. The product was dark purple. The polyol synthesized had a hydroxyl number of 258 meq/g, an unsaturation of 0.0010 meq/g, a polydispersity of 1.04, and a viscosity of 75 cps.

Although the invention has been described in detail in the foregoing for the purpose of illustration, it is to be understood that such detail is solely for that purpose and that variations can be made therein by those skilled in the art without departing from the spirit and scope of the invention except as it may be limited by the claims.

Claims (21)

1. An activation starting mixture comprising:

a) at least one preactivated starting compound comprising:

i) at least one first hydroxy-functional starting compound having a hydroxy functionality of from 1 to 8 and an equivalent weight of at least 70;

ii) at least one epoxide; and

iii) at least one DMC catalyst; and

b) at least 2 mole% of at least one second hydroxy-functional starting compound having a hydroxyl functionality of 1 to 8 and an equivalent weight less than that of the first starting compound.

2. The mixture of claim 1, wherein the equivalent weight of the first starting compound is greater than or equal to 200.

3. The mixture of claim 1, wherein the equivalent weight of the second starting compound is less than or equal to 80.

4. The mixture of claim 1, wherein the first starting compound is a polyoxypropylene polyol, a polyoxyethylene polyol, a polytetramethylene ether glycol, a propoxylated glycerin, a tripropylene glycol, an alkoxylated allylic alcohol, or mixtures thereof.

5. The mixture of claim 1, wherein the second starting compound is water, propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, glycerol, trimethylolpropane, sorbitol, methanol, ethanol, butanol, polyoxypropylene polyol, polyoxyethylene polyol, alkoxylated allylic alcohol, or mixtures thereof.

6. The mixture of claim 1, wherein the preactivated starting compound is mixed with at least 80 mole% of the second starting compound.

7. The mixture as recited in claim 1 wherein the double metal cyanide catalyst is zinc hexacyanocobaltate.

8. A process for preparing an activated starter mixture comprising combining:

a) at least one preactivated starting compound comprising:

i) at least one first hydroxy-functional starting compound having a hydroxy functionality of from 1 to 8 and an equivalent weight of at least 70;

ii) at least one epoxide; and

iii) at least one DMC catalyst; and

b) at least 2 mole% of at least one second hydroxy-functional starting compound having a hydroxyl functionality of 1 to 8 and an equivalent weight less than that of the first starting compound.

9. The method of claim 8, wherein the equivalent weight of the first starting compound is greater than or equal to 200.

10. The process of claim 8, wherein the equivalent weight of the second starting compound is less than or equal to 80.

11. The process of claim 8, wherein the first starting compound is a polyoxypropylene polyol, a polyoxyethylene polyol, a polytetramethylene ether glycol, a propoxylated glycerin, a tripropylene glycol, an alkoxylated allylic alcohol, or mixtures thereof.

12. The process of claim 8 wherein the second starting compound is water, propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, glycerol, trimethylolpropane, sorbitol, methanol, ethanol, butanol, polyoxypropylene polyol, polyoxyethylene polyol, alkoxylated allylic alcohol, or mixtures thereof.

13. The method of claim 8, wherein the preactivated starting compound is mixed with at least 80 mole% of the second starting compound.

14. The process of claim 8 wherein the double metal cyanide catalyst is zinc hexacyanocobaltate.

15. A batch or semi-batch process for the polyaddition of alkylene oxides to an activated starting mixture comprising reacting:

1.) at least one activating starting mixture comprising a mixture of:

a) at least one preactivated starting compound comprising:

i) at least one first hydroxy-functional starting compound having a hydroxy functionality of from 1 to 8 and an equivalent weight of at least 70;

ii) at least one epoxide; and

iii) at least one DMC catalyst; and

b) at least 2 mole% of at least one second hydroxy-functional starting compound having a hydroxyl functionality of 1 to 8 and an equivalent weight less than that of the first starting compound; and

2.) at least one epoxide.

16. The batch or semi-batch process of claim 15, wherein the equivalent weight of the first starting compound is greater than or equal to 200.

17. The batch or semi-batch process of claim 15, wherein the equivalent weight of the second starting compound is less than or equal to 80.

18. The batch or semi-batch process of claim 15, wherein the first starting compound is a polyoxypropylene polyol, a polyoxyethylene polyol, a polytetramethylene ether glycol, a propoxylated glycerin, a tripropylene glycol, an alkoxylated allylic alcohol, or mixtures thereof.

19. The batch or semi-batch process of claim 15, wherein the second starting compound is water, propylene glycol, dipropylene glycol, tripropylene glycol, neopentyl glycol, diethylene glycol, triethylene glycol, glycerol, trimethylolpropane, sorbitol, methanol, ethanol, butanol, polyoxypropylene polyols, polyoxyethylene polyols, alkoxylated allylic alcohols, or mixtures thereof.

20. The batch or semi-batch process of claim 15, wherein the preactivated starting compound is mixed with at least 80 mole percent of the second starting compound.

21. A batch or semi-batch process as set forth in claim 15 wherein the double metal cyanide catalyst is zinc hexacyanocobaltate.