JPH08253565A - Production of polyether ester polyol - Google Patents

Abstract

PURPOSE: To obtain a polyether ester polyol useful for e.g. an elastic fiber by polymerizing tetrahydrofuran, 3-methyltetra-hydrofuran and β-methyl-δ- valerolactone in the presence of a specified catalyst. CONSTITUTION: Tetrahydrofuran (A), 3-methyltetrahydrofuran (B) and β-methyl-δ- valerolactone (C) are polymerized together in the presence of a catalyst comprising perchloric acid and acetic anhydride to make a polyether ester polyol useful as a starting polyol for an elastomer having rubbery elasticity of polytetra- methylene ether glycol. The molar ratio A:B:C is 1:(0.01-0.6): (0.02-0.7). The amount of the perchloric acid used is 0.003-0.03mol, and that of the acetic anhydride used is 0.05-0.25mol. The obtained polyether ester polyol has a low crystalline melting point and is a starting material for a polyurethane resin, such as an elastic fiber or an elastomer, having good resistance to wet-heat decomposition.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing a polyetherester polyol. More specifically, polytetramethylene ether glycol (hereinafter PTMEG
(Abbreviated as)) has a rubber elastic property,
The present invention relates to a method for producing a polyether ester polyol useful as a polyol for elastic fibers and elastomer raw materials.

[0002]

2. Description of the Related Art PTME, a polyether polyol
G reacts with various isocyanate compounds to form a polyurethane resin having excellent rubber elasticity and abrasion resistance. Such resins are widely used as materials for molding and processing as paints and adhesives, and as thermoplastic and thermosetting resins for automobile parts, home appliances, machine parts and the like. And since it has excellent rubber elasticity, it has a number average molecular weight of 500 to 5
000 PTMEG is also used as an elastic fiber (spandex). As a part of further enhancing the characteristics of such elastic fiber, improvement of heat setting property of the obtained fiber at low temperature is required. As a countermeasure, for example, Japanese Patent Application Laid-Open No. 2-19511 discloses the use of a polyether polyol having a reduced crystallinity.
Also, in the field of application of paints and adhesives, reduction of the viscosity by lowering the crystallinity of the resin and the raw materials is being studied from the viewpoint of workability and curability.

As such an improved technique, a polyol obtained by a ring-opening copolymerization reaction of tetrahydrofuran (hereinafter abbreviated as THF) which is a raw material of PTMEG and a cyclic ether compound such as ethylene oxide, propylene oxide and alkyltetrahydrofuran is known. Has been. Further, a copolymer of THF and a cyclic ester compound (lactone) has also been studied, and for example, a method of copolymerizing THF, lactone and polyhydric alcohol with a heteropolyacid is known.

[0004]

THM is a method for reducing the crystallinity while maintaining the characteristics of PTMEG.
It is known to copolymerize F with alkyltetrahydrofuran, but this method is slow in the copolymerization reaction, and it is difficult to contain a large amount of alkyltetrahydrofuran in the main chain. When a copolymerizable polyol having a low content of is used as a raw material for a polyurethane resin or another resin, there is a problem that the characteristics of the obtained resin are not remarkable.
Further, in the polyether ester polyol obtained by the copolymerization reaction of THF and lactone using the above heteropoly acid, (i) the backbone derived from THF is introduced into the main chain, and (ii) the industrially useful molecular weight is used. Yes 500-5
In order to obtain 000 polyether ester polyol, polyhydric alcohol is indispensable, and when it is produced without using polyhydric alcohol, the content of the group derived from lactone is increased, and it is easily hydrolyzed. There is a problem that the rubber elastic property, which is a characteristic of PTMEG, is deteriorated.

Further, when these copolymerization reactions are carried out with a fuming sulfuric acid or fluorosulfonic acid type catalyst as a catalyst, hydrolysis must be carried out under acidic conditions as a post-treatment after the reaction, so that β-methyl-δ-valero is required. The ester bond portion derived from the lactone is cleaved, and the intended polyol cannot be obtained. Further, among the lactones, the polyester polyol obtained by ring-opening polymerization of ε-caprolactone has excellent heat resistance, but has a problem of poor wet heat decomposition resistance. The purpose of the present invention is to provide these PTMs.
A method for producing a polyether ester polyol having a number average molecular weight of 500 to 5,000, which is useful as a raw material for elastic fibers and elastomers, which has reduced crystallinity while maintaining the rubber elastic properties of EG and has good resistance to wet thermal decomposition. To provide.

[0006]

The object of the present invention is to obtain THF.
And 3-methyl-tetrahydrofuran and β-methyl-δ-
The three valero lactons were converted into THF: 3-methyl-tetrahydrofuran: β-methyl-δ-valerolactonone = 1: 3.
Achieved by a production method in which a target polyetherester polyol is obtained by polymerizing in the presence of a catalyst of perchloric acid and acetic anhydride at a charged molar ratio of 0.01 to 0.6: 0.02 to 0.70. can do. In the present production method, a polyether ester polyol having a number average molecular weight of 500 to 5,000, preferably 1,000 to 4,000 can be obtained by appropriately adjusting the amount of catalyst, the reaction temperature, and the reaction time.

By this manufacturing method, the crystallinity is lowered while maintaining the rubber elastic properties of PTMEG.
A number average molecular weight of 500, which is good as a raw material for polyurethane resins such as elastic fibers and elastomers, which has good resistance to moist heat decomposition.
It is possible to obtain polyetherester polyols having ˜5000. When producing this polyether ester polyol, polymerization is performed under the same conditions as above without using 3-methyl-tetrahydrofuran, and the obtained polyether ester polyol is the polyether ester polyol obtained by the production method of the present invention. The melting point is remarkably high as compared with, and the object of the present invention cannot be achieved.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a polyetherester polyol of the present invention can be carried out as follows. TH
F and 3-methyl-tetrahydrofuran were charged at a mixing molar ratio of 1: 0.01 to 0.6, and perchloric acid was charged at 0.003 to 0.03 mol, and the mixture was cooled to 5 ° C. or lower. While maintaining the mixture at 5 ° C. or lower, 0.02 to 0.70 of β-methyl-δ-valerolactone and 0.05 to 0.25 mol of acetic anhydride are added dropwise to 1 mol of the above THF. After completion of the dropping, the temperature is raised to around 10 to 20 ° C. to perform the aging reaction. The reaction time is 1 to 15 hours.

In the post-treatment, after neutralizing the reaction solution and recovering unreacted raw materials, 150 ml of 1-butanol was added to 100 g of the product oil layer and 5% of 30% sodium hydroxide aqueous solution was added.
-80 ml is added and the product and terminal acetate are hydrolyzed by heating and stirring at 70 to 95 ° C for 2 to 5 hours, and after completion, neutralization, dehydration and filtration operations are performed to remove 1-butanol. By doing so, the intended polyether ester polyol can be obtained. The composition ratio of the components constituting the obtained polyetherester polyol which is a copolymer is 5 to 45 mol% of 3-methyl-tetrahydrofuran and β-methyl-δ-based on 50 mol% of the structural unit derived from THF. Valerolactone is 5-45 mol%
Is.

[0010]

EXAMPLES Next, examples will be described in detail. The number average molecular weights shown in the examples are based on the hydroxyl value determined by the phthalic anhydride analysis method. The copolymerization composition ratio and crystalline melting point of the produced polyol were determined by ¹ H-NMR measurement and measurement with a differential scanning calorimeter.

[Example-1] THF was added to a 1-liter four-necked flask equipped with a stirrer, a thermometer and a dropping funnel.
6.4 g and 3-methyl-tetrahydrofuran 74.5 g
, Cool to 0 ° C, and add 71% perchloric acid aqueous solution 1
0.2 g was added. Then, after maintaining at 0 ° C., about 20% (15 g) of 73.8 g of acetic anhydride was added dropwise over 30 minutes, and at that time, 16.1 g of β-methyl-δ-valerolactone.
Also, the dropping was started, and the dropping was completed in 20 minutes. During this period, acetic anhydride was continuously added dropwise, and the whole amount was added dropwise in 1 hour and 30 minutes. During the dropping, the internal temperature was raised to 10 ° C. and the reaction was continued for 4 hours.
When water was added at the end of the reaction and left to stand, an oil layer and an aqueous layer were separated, so the aqueous layer was removed, and then the oil layer was washed with water to make the liquid neutral. Next, 100 ml of 1-butanol and 40 ml of a 30% by weight sodium hydroxide aqueous solution were added, and hydrolysis was carried out at a temperature of 85 to 90 ° C. for 3 hours. After hydrolysis and washing with water, an aqueous hydrochloric acid solution is added, and the solution is acidified at 45 to 50 ° C. for 3 days.
Stir for 0 minutes. After stirring and washing with water to make the liquid neutral, dehydration and filtration operations were performed, and 1-butanol was distilled off under reduced pressure to obtain 185 g of a colorless transparent viscous liquid. The number average molecular weight, crystalline melting point and TH of this product
F, 3-methyl-tetrahydrofuran, β-methyl-δ
-The content of the structural unit derived from valerolactone is shown in Table 1. In Table 1, a group derived from —O (CH ₂ ) ₄ —: tetrahydrofuran —CH ₂ CH (R ₁ ) CH (R ₂ ) CH ₂ O—: a group derived from 3-methyl-tetrahydrofuran (provided that R ₁ , R ₂
One of them is hydrogen and the other is a methyl group. ) —O (CH ₂ ) ₂ CH (CH ₃ ) CH ₂ CO—: a group derived from β-methyl-δ-valerolactone

[0012]

[Table 1]

[Example-2] 266.4 g of THF and 58.1 g of 3-methyl-tetrahydrofuran were charged in the same apparatus as in Example-1, cooled to 0 ° C, and 7.3 g of 71% perchloric acid aqueous solution was added. After that, the liquid temperature was maintained at 0 ° C. and acetic anhydride 7
4.0 g and β-methyl-δ-valerolactone 37.6 g
Was dripped. The time required for dripping is 1 hour 40 minutes for acetic anhydride,
β-methyl-δ-valerolactone was 1 hour. After the dropping, the reaction is continued at 10 ° C. for 4 hours and the same post-treatment as in Example 1 is performed to obtain a colorless transparent viscous liquid 1.
67 g was obtained. Table 1 shows the number average molecular weight, crystalline melting point, and constituent unit contents derived from THF, 3-methyl-tetrahydrofuran, and β-methyl-δ-valerolactone of this product.

[Example-3] 266.4 g of THF and 40.8 g of 3-methyl-tetrahydrofuran were charged in the same apparatus as in Example-1, cooled to 0 ° C, and 7.1 g of 71% aqueous perchloric acid solution was added. After that, the liquid temperature was maintained at 0 ° C., and 72.7 g of acetic anhydride and β-methyl-δ-valerolactone 53.
4 g was added dropwise. The time required for dripping is 5 hours for acetic anhydride.
0 minutes, β-methyl-δ-valerolactone was 1 hour. After completion of dropping, the reaction was continued at 10 ° C. for 4 hours, and
By performing the same post-treatment as in Example 1, 145 g of a colorless transparent viscous liquid was obtained. Table 1 shows the number average molecular weight, crystalline melting point, and constituent unit content derived from 3-methyl-tetrahydrofuran and β-methyl-δ-valerolactone of this product.

Example 4 266.4 g of THF and 28.6 g of 3-methyl-tetrahydrofuran were charged in the same apparatus as in Example 1, cooled to 0 ° C., and 7.3 g of 71% perchloric acid aqueous solution was added. After the addition, the liquid temperature was maintained at 0 ° C., and 73.9 g of acetic anhydride and β-methyl-δ-valerolactone 7 were added.
6.4 g was added dropwise. The time required for the dropping was 1 hour 40 minutes for acetic anhydride and 1 hour 20 for β-methyl-δ-valerolactone.
It was a minute. After the dropping is completed, the reaction is continued at 10 ° C for 4 hours,
By performing the same treatment as in Example-1, 120 g of a colorless and transparent viscous liquid was obtained. The number average molecular weight of this product,
Table 1 shows the crystalline melting point and the content of the structural units derived from THF, 3-methyl-tetrahydrofuran and β-methyl-δ-valerolactone.

[Examples 5 to 8] The polyether ester polyols obtained in Examples 1 to 4 were mixed with 4,4'-diphenylmethane diisocyanate (MDI) in excess.
A urethanization reaction is performed to prepare a prepolymer, the chain length of which is extended with 1,4-butanediol (1,4BD), casting is performed, and heat curing is performed at 100 ° C. for 16 hours. The mechanical properties were measured according to JISK-6301. The results are shown in Table 2.

[0017]

[Table 2]

[Example-9] The test piece of the polyurethane resin obtained in Example-5 (using the polyol of Example-1) was placed in a constant temperature and humidity chamber at 70 ° C x 95% RH for 1 week. It sampled every time. After being left for 24 hours or more after sampling, its tensile properties were measured. The results are shown in Table 3.
It was shown to.

[0019]

[Table 3]

Comparative Example-1 250.0 g of THF was charged in the same apparatus as in Example-1, cooled to 0 ° C., 8.3 g of 71% perchloric acid aqueous solution was added, and the liquid temperature was kept at 0 ° C. , 60.6 g of acetic anhydride and β-methyl-δ-valerolactone 4
3.9 g was added dropwise. The time required for the dropping was 1 hour and 50 minutes for acetic anhydride and 1 hour for β-methyl-δ-valerolactone. After the dropping was completed, the reaction was continued at 10 ° C. for 4 hours and the same treatment as in Example-1 was performed to obtain 149 g of a colorless transparent viscous liquid. Table 1 shows the number average molecular weight, crystalline melting point, and constituent units derived from THF and β-methyl-δ-valerolactone of this product.

Comparative Example-2 150.0 g of THF was charged in the same apparatus as in Example-1, cooled to 0 ° C., 5.7 g of 71% perchloric acid aqueous solution was added, and the liquid temperature was kept at 0 ° C. Then, 40.9 g of acetic anhydride and 59.4 g of β-methyl-δ-valerolactone were added dropwise. The time required for the dropping was 1 hour and 40 minutes for acetic anhydride and 1 hour for β-methyl-δ-valerolactone. After the dropping is completed, the reaction is continued at 10 ° C for 4 hours,
By performing the same treatment as in Example-1, 65 g of a colorless transparent viscous liquid was obtained. Table 1 shows the number average molecular weight, crystalline melting point, and constituent unit contents derived from THF and β-methyl-δ-valerolactone of this product.

Comparative Examples -3 and -4 Comparative Examples -1 and-
The polyether ester polyol obtained in 2 was added to 4,
A resin cured by preparing a prepolymer by carrying out a urethanization reaction in the presence of excess 4′-diphenylmethane diisocyanate (MDI) and extending the chain length with 1,4-butanediol (1,4BD). The mechanical properties of are shown in Table 2.

[Comparative Example-5] Polycaprolactone obtained by ring-opening polymerization of ε-caprolactone (PCL; manufactured by Daicel Corp .; number average molecular weight 1989) was used in the same manner as in Example-5 to prepare a polyurethane resin (excess NCO 6.3). %; Prepolymer / 1,4-BD equivalent ratio 1.05) was prepared. Moisture and thermal decomposition resistance of this test piece was measured in the same manner as in Example-9, and the results are shown in Table 3.

[0024]

EFFECTS OF THE INVENTION According to the production method of the present invention, a group derived from THF, 3-methyl-tetrahydrofuran or β-methyl-δ-valerolactone can be easily introduced into the main chain, and it has a lower crystalline melting point. As a raw material for polyurethane resins such as elastic fibers and elastomers, which have good resistance to moisture and thermal decomposition,
It is possible to produce polyetherester polyols that give excellent mechanical properties.

Claims (1)

[Claims] 1. A method for producing a polyether ester polyol, which comprises polymerizing tetrahydrofuran, 3-methyl-tetrahydrofuran, and β-methyl-δ-valerolactone in the presence of a catalyst of perchloric acid and acetic anhydride.