JPH0730176B2 - Method for synthesizing polyalkylene ether polyol - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Field of Application> The present invention uses a novel polymerization catalyst to polymerize a mixture of tetrahydrofuran (hereinafter abbreviated as “THF”) and another cyclic ether copolymerizable therewith to obtain an oxyether. The present invention relates to a method for producing a copolymerized polyether glycol having a tetramethylene group in the molecule.

<Prior Art> Polyoxytetramethylene glycol (hereinafter abbreviated as PTMG), which is a homopolymer of THF, is mainly used as a polyalkylene ether glycol that is a raw material of polyurethane used for spandex and synthetic leather.

However, the soft segment of the urethane elastomer using PTMG is likely to be crystallized at a low temperature, and there has been a problem that the physical properties at a low temperature, for example, the recovery rate after applying tension is not sufficient.

As one of the solutions to this problem, a copolymer of THF and another cyclic ether has been studied as a polyalkylene ether glycol that replaces PTMG.

Polymerization catalysts for these copolymerized polyalkylene ether glycols include boron trifluoride (BF ₃ ) etherate, fuming sulfuric acid, fluorosulfuric acid, naphthoion resin, etc.
32200, JP-B-45-3104, JP-A-58-12571
No. 8 and Japanese Patent Publication No. 54-162796) are known.

<Problems to be Solved by the Invention) However, the reactions using these known catalysts each have drawbacks. That is, in the reaction using BF ₃ -etherate, fuming sulfuric acid, fluorosulfuric acid, the hydrolysis process makes recycling of the catalyst extremely difficult, and fuming sulfuric acid and fluorosulfuric acid have strong corrosive properties. In the reaction using Nafion resin, the catalyst can be dried and reused after adding water, but it is extremely difficult to dry the catalyst, and the activity decreases due to the presence of water. At about
Hold at constant pressure at 0.1 Torr until constant weight or require azeotropic distillation with liquid hydrocarbons.

<Means for Solving Problems> Under such circumstances, the present inventors carry out polymerization in the coexistence of water or a polyhydric alcohol to obtain polyalkylene ether glycol having an OH group at one end, and further recycling. As a result of earnest research on a catalyst that can be used, it was found that a heteropoly acid or a salt thereof in which 0.1 to 15 molecules of limited water are coordinated or present per heteropolyanion achieves its purpose, The present invention has been completed.

Further, according to the present invention, it was found that an oligomeric cyclic ether, which is a polymer of THF, can also be copolymerized with THF.
It was found that an oligomeric cyclic ether can be used as a raw material for G synthesis.

That is, the present invention provides 0.1 to 15 per heteropolyanion.
Using a heteropoly acid and / or salt thereof in which molecular water is coordinated or present as a catalyst, tetrahydrofuran, another cyclic ether copolymerizable therewith and water and / or a diol having 2 to 6 carbon atoms are reacted. , A method for synthesizing a polyalkylene ether polyol.

Usually, the heteropoly acid or a salt thereof is present as a hydrate of 20 to 40 molecules per molecule, but in this state, it may be contacted with a mixture of THF and another cyclic ether copolymerizable therewith. No polymerization activity was observed.

However, when the above-mentioned heteropolyacid or a salt thereof was dried and the hydration number was changed, and then the polymerization activity was investigated, it was surprisingly found that the amount of water in the catalyst phase was changed to the heteropolyanion 1.
It was found that when the number of molecules per molecule is 15 or less, the polymerization activity appears unexpectedly and the terminal of the obtained polymer is OH group, and the direct copolymerized polyalkylene ether polyol is obtained. Especially, when the hydration number is 8 or less, it has more rapid activity.

The hydration number can be adjusted by heating the heteropolyacid or a salt thereof to a high temperature or holding it under reduced pressure at a relatively low temperature. It can also be adjusted by mixing a predetermined amount of water with THF and cyclic ether from a state where the hydration number is less than required and supplying the mixture. It is presumed that most of the water present in the system exists in the state of being coordinated with the heteropolyacid or its salt.

Water existing in the polymerization system is consumed due to OH conversion at the terminal as the polymerization proceeds, and the number of coordinated waters of the heteropolyacid or its salt decreases. When the amount of water coordinated to the heteropolyacid or its salt decreases, the molecular weight of the resulting polymer becomes high, and when the number of coordinated water becomes 0.1 molecule or less, the efficiency of the terminal OH group also deteriorates. It is necessary to control the water in the system so as to be 0.1 to 15, more preferably 1.1 to 8.

It is also possible to use a diol instead of or as a part of water. In the reaction in which the diol is incorporated into the polymer chain by an ether bond, water is produced.Therefore, it is necessary to prevent the coordination water number from exceeding 15 due to the water produced in the system in excess of the amount consumed as the polymer terminal. is there.

When the number of coordinated waters of the heteropolyacid or its salt exceeds 15, the polymerization activity disappears as described above, but the number of actively coordinated waters for polymerization varies depending on the type of the heteropolyacid or its salt. To do. Further, since the molecular weight of the polymer to be synthesized varies depending on the number of coordinated waters, when synthesizing a polymer having almost the same molecular weight, it is determined by the kind of the heteropolyacid or its salt and the desired molecular weight. It is necessary to control the number of suitable coordinated water to carry out the reaction.

The coordination water number of the heteropolyacid used in the present invention is, for example, 3 at 250 ° C. for a normal heteropolyacid having a coordination water number of 20 to 40.
It can be controlled by a method such as heating for a time.

The catalyst used in the present invention is the lower phase of the two liquid phase in the polymerization system,
Alternatively, it exists as a solid phase. After the polymerization, the polymerization product and the catalyst can be easily separated by a usual method such as phase separation or filtration, and the separated catalyst can be recycled.

Heterolipoic acid and salts thereof in the present invention, Mo, W, V, at least one oxide, and other elements, for example,
Heteropolyacids and salts thereof, which are a general term for oxyacids produced by condensation of oxyacids such as P, Si, As, Ge, B, Ti, Ce, Co.

Specific examples of these heteropolyacids and salts thereof, phosphomolybdic acid, phosphotungstic acid, phosphomolybdotungstic acid, phosphomolybdovanadic acid, phosphomolybdotungstovanadic acid, phosphotungstovanadic acid, phosphomolybdoniobic acid, Tungstosilicic acid, silicomolybdic acid, silicomolybdotungstic acid, silicomolybdotungstovanadic acid, germanium tungstic acid, borotungstic acid, boromolybdic acid, boomolybdotungstic acid, boomolybdovanadic acid, homolybdotungstovanadine Acid, cobalt molybdic acid, cobalt tungstic acid, arsenic molybdic acid, arsenic tungstic acid, titanium molybdic acid, cerium molybdic acid, and salts thereof. The type of salt is not particularly limited, but examples thereof include Group I of the periodic table such as Li, Na, K, Rb, Cs, Cu, Ag, Au, Mg, Ca,
Group II of Sr, Ba, Zn, Cd, Hg etc., III of Sc, La, Ce, Al, Ga, In etc.
Group VIII, Group VIII such as Fe, Co, Ni, Ru, Pd, and Pt, and metal salts such as Sn, Pb, Mn, and Bi, ammonium salts, amine salts, and the like. Examples of these salts include 12-tungstophosphoric acid-1-lithium (LiH ₂ PW ₁₂ O ₄₀ ), 12-tungstophosphoric acid-2-lithium (Li ₂ HPW ₁₂ O ₄₀ ), 12-tungstophosphoric acid- 1-Sodium (NaH ₂ PW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-2-
Sodium (Na ₂ HPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-2
− Potassium (K ₂ HPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-2
-Cesium (Cs ₂ HPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-2
-Silver (Ag ₂ HPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-1-magnesium (MgHPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-1-
Calcium (CaHPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-1
-Zinc (ZnHPW ₁₂ O ₄₀ ), 12-Tungstosilicic acid-1-nickel (NiHSiW ₁₂ O ₄₀ ), 12-Tungstosilicic acid-2-lithium (Li ₂ H ₂ SiW ₁₂ O ₄₀ ), 12-Tungstosilicic acid-2-
Silver (Ag ₂ H ₂ SiW ₁₂ O ₄₀ ), 12-Tungstosilicic acid-1-magnesium (MgH ₂ SiW ₁₂ O ₄₀ ), 12-Tungstosilicic acid-1
-Aluminum (AlHSiW ₁₂ O ₄₀ ), 12-tungstosilicic acid-1-indium (InHSiW ₁₂ O ₄₀ ), 12-tungstosilicic acid-1-gallium (GaHSiW ₁₂ O ₄₀ ), 12-molybdophosphoric acid-1-lithium (LiH ₂ PM ₁₂ O ₄₀ ), 12-molybdophosphoric acid-
1- magnesium (MgHPMo ₁₂ O _40), 12- tungstophosphoric acid-2-ammonium _{((NH 4) 2 HPMo 12} O 40), 12- tungstosilicic acid 1-tetramethyl-amine _{(N (CH 3) 4 H} 3
SiW ₁₂ O ₄₀ ), 12-tungstophosphoric acid-1-aluminum (AlPW ₁₂ O ₄₀ ), 12-tungstophosphoric acid-1-gallium (GaPW ₁₂ O ₄₀ ), 12-tungstophosphoric acid-1-indium (InPW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-1-chromium (Cr
PW ₁₂ O ₄₀ ), 12-Tungstophosphoric acid-1-bismuth (BiPW
₁₂ O ₄₀ ), 12-Tungstophosphate-1-iron (FePW ₁₂ O ₄₀ ).
Etc. can be mentioned. Heteropoly acid salt is an aqueous solution of heteropolyphosphoric acid, carbonate or nitrate of various metals, ammonia,
It is prepared by titrating with an amine or the like and evaporating to dryness.

The amount of the heteropolyacid and its salt to be used is not particularly limited, but when the amount of the heteropolyacid or its salt in the reactor is small, the polymerization rate is low, and 0.01 to 10 times the amount of THF, preferably 0.1 to 3 times the amount used. To be done.

The THF and cyclic ethers used in the polymerization preferably do not contain impurities such as peroxides. For water,
It is important to control so as to maintain the amount of hydration to the heteropoly acid in the reaction system.

Specific examples of the cyclic ether copolymerizable with tetrahydrofuran include ethylene oxide, propylene oxide,
Isobutylene oxide, 3-membered ring ether such as epichlorohydrin, oxetane, 3,3-dimethyloxetane,
4-membered ring ethers such as 3-methyloxetane and 3,3-bis (chloromethyl) oxetane, 5-membered ring ethers such as methyltetrahydrofuran and 1,3-dioxolane, 6-membered ring ethers such as trioxane and its derivatives, oxepane and 7-membered ring ether such as its derivative, THF or T
An oligomeric cyclic ether, which is a polymer of HF and alkylene oxide, can be mentioned. The composition of the copolymer can be changed in the range of THF content of 1 to 99.5% by weight, and a random or block copolymer can be obtained depending on the conditions.

The diol having 2 to 6 carbon atoms used in place of water in the present invention may be any diol having no substituent that inhibits the activity of the catalyst. For example, ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,
Examples include 5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol and dipropylene glycol.

It is also possible to introduce an alkoxy group at the terminal by allowing a monoalcohol to exist as the alcohol.

When the reaction temperature is increased, the degree of polymerization tends to decrease, and in view of the polymerization yield, it is preferably -10 to 150 ° C, particularly preferably 30 to 100 ° C. 150
When the temperature exceeds ℃, the yield decreases drastically, and the reactivity is extremely low at the -10 ℃ end.

The time required for the reaction varies depending on the amount of catalyst and the reaction temperature, but is 0.5 to 20 hours.

The reaction can be carried out while stirring the heteropoly acid or salt thereof with THF and other cyclic ethers copolymerizable with it, so that a solvent is not necessary, but an inert one for the reaction May be added.

As the reaction type, a commonly used one such as a tank type or a tower type is used. Both batch type and continuous type can be carried out.

The catalyst may be supported on activated carbon, silica-alumina or the like by a known method, or may be used as a fixed bed as it is when the catalyst is a solid in the reaction system, and the supported catalyst may be used as a fluidized bed. You may use.

After the reaction, the polyalkylene ether polyol can be obtained by separating the unreacted monomers, preferably by distillation or the like, from the upper layer, which is mainly composed of the polymerization product and its monomer, by layer separation or the like.

Further, the heteropoly acid is relatively weak in corrosiveness and is advantageous in terms of the material of the apparatus. Moreover, since the polymerization end is OH, the hydrolysis step is not necessary and the catalyst can be recycled.

<Examples> Hereinafter, the present invention will be described with reference to Examples.

Example 1 200 g of THF, 8.0 g of propylene oxide, and 2.5 g of water are charged into a container equipped with a stirrer and a reflux condenser. Then 250 ° C
Then, 100 g of phosphotungstic acid (H ₃ PW ₁₂ O ₄₀ ) which has been heated to an anhydrous state for 3 hours is added (the added water makes the coordinated water number of phosphotungstic acid about 4). The temperature is set to 60 ° C., stirring is continued for 4 hours, and then the mixture is left standing at room temperature to separate into two phases. Unreacted THF was distilled off from the upper phase to obtain 53 g of a transparent and viscous polymer. ^{1 of the} obtained polymer
As a result of H-NMR and ¹³ C-NMR measurement, the polymer was OH at both ends.
It was a group, and it was found to be a polyalkylene ether glycol in which one molecule of propylene oxide was copolymerized on average in two molecules. The number average molecular weight was 1,600 as a result of GPC measurement.

Comparative Example 1 The same operation as in Example 1 was carried out except that phosphotungstic acid having a coordinated water number of 16 was used, but no polymer was obtained.

Examples 2 to 14 and Comparative Examples 2 to 3 A container equipped with a stirrer and a reflux condenser was charged with THF containing 10 ppm of water.
Charge 100 g and 4 g of propylene oxide. To this 150
Heat in an electric furnace at a temperature of ~ 300 ℃ for 0.5 ~ 2 hours.
50 g of the heteropoly acid or salt thereof adjusted to a constant coordination water number shown in 1 is added. The temperature is set to 60 ° C., stirring is continued for 5 hours, and the mixture is left standing at room temperature to separate into two phases. Unreacted monomers were distilled off from the upper phase to obtain a transparent and viscous THF / propylene oxide copolymer. The results are shown in Table-1.

Example 15 In a container equipped with a stirrer and a reflux condenser, 200 g of THF and Table-2 were used.
The amount of cyclic ether shown in Table 2 is charged. Next, phosphotungstic acid (H ₃ PW ₁₂ O ₄₀
・ Add 100g of 4H ₂ O). The temperature is set to 60 ° C., the reaction is continued for 4 hours, and the mixture is left standing at room temperature to separate into two phases. Unreacted monomers were distilled off from the upper phase to obtain a transparent and viscous polymer in the amounts shown in Table 2. The polymer obtained is
^{As a result of 1} H-NMR and ¹³ C-NMR measurements, it was a polyalkylene ether glycol in which a cyclic ether was copolymerized in the polyoxytetramethylene chain. The number average molecular weight was determined by GPC (gel permeation chromatography) measurement.

Example 16 THF 200 g and the general formula in a container equipped with a stirrer and a reflux condenser. (However, 2 ≦ n ≦ 9) 10 g of oligomeric cyclic polytetramethylene ether is added. Next, 100 g of phosphotungstic acid (H ₃ PW ₁₂ O ₄₀・ 4H ₂ O) whose coordination water number was adjusted to 4 was used.
g add. The temperature is set to 60 ° C., the reaction is continued for 10 hours, and the mixture is allowed to stand at room temperature to separate into two phases. Unreacted monomer was distilled off from the upper phase to obtain 42 g of PTMG. This PTMG contained 0.5 g of oligomeric cyclic polytetramethylene ether, and 0.4 g in the catalyst phase. From this result, it was found that the oligomeric cyclic polytetramethylene ether was copolymerized with THF to form PTMG.

Example 17 49 g of a transparent and viscous polymer was obtained in the same manner as in Example 1 except that 13 g of 1,4-butanediol was charged instead of 2.5 g of water. As a result of analysis, the obtained polymer was a polyalkylene ether glycol in which both terminals had OH groups and an average of 2 molecules of propylene oxide were copolymerized in one molecule. The number average molecular weight was 1,500 as a result of GPC measurement.

Continuation of front page (56) References JP-A-59-159824 (JP, A)

Claims (1)

[Claims] 1. Tetrahydrofuran, another cyclic ether copolymerizable therewith and water, which is used as a catalyst for a heteropolyacid and / or a salt thereof in which 0.1 to 15 molecules of water are coordinated or present per heteropolyanion. And / or reacting a diol having 2 to 6 carbon atoms, a method for synthesizing a polyalkylene ether polyol.