METHOD FOR PREPARING POLYESTER POLYOL

Abstract

The present application discloses a method for preparing polyester polyol comprising performing transesterification of raw materials containing inorganic oxyacid ester and polyhydric alcohol to obtain the polyester polyol. The polyester polyol obtained by the method described in the present application has higher heat resistance.

Claims

1. A method for preparing polyester polyol comprising performing transesterification of raw materials containing inorganic oxyacid ester and polyhydric alcohol to obtain the polyester polyol.

2. The method according to claim 1, wherein the inorganic oxyacid ester is at least one of compounds having a chemical formula shown in Formula I and Formula II,
M(OR.sup.1).sub.n.sup.1   Formula I
O═P(OR.sup.2).sub.n.sup.2   Formula II wherein, M is a metal element or a non-metal element that does not include P, R.sup.1 and R.sup.2 are independently selected from at least one of C.sub.1 to C.sub.8 alkyl groups, n.sup.1=2˜8, n.sup.2=2˜8.

3. The method according to claim 2, wherein M is B, Si, Ge, Al, Ti, Fe, Sn, V, Ga, Zr, Cr, Sb or W.

4. The method according to claim 1, wherein inorganic oxyacid ester comprises at least one of trimethyl borate, triethyl borate, tripropyl borate, tributyl borate, tri-n-hexyl borate, triisooctyl borate, trioctyl borate, tetramethoxysilane, tetraethyl orthosilicate, tetrapropyl silicate, tetrabutyl silicate, ethyl orthogermanate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tri-n-pentyl phosphate, trihexyl phosphate, aluminium ethoxide, aluminum isopropoxide, aluminum n-butoxide, aluminum tert-butoxide, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetrahexyl titanate, tetraisooctyl titanate, tetrabutyl ferrite, tetrabutyl stannate, butyl orthovanadate, gallium ethoxide, tetra-n-propyl zirconate, tetrabutyl zirconate, tert-butyl chromate, ethyl antimonite, butyl antimonate, tungsten ethoxide and tungsten isopropoxide.

5. The method according to claim 1, wherein a molar ratio of inorganic oxyacid ester, polyhydric alcohol and transesterification catalyst satisfies: inorganic oxyacid ester:polyhydric alcohol=(0.8˜1.2)n.sup.3/x, wherein x is the number of moles of alkoxyl groups contained in each mole of inorganic oxyacid ester, and n.sup.3 is the number of moles of hydroxyl groups contained in each mole of polyhydric alcohol.

6. The method according to claim 1, wherein the number of hydroxyl groups in the polyhydric alcohol is not less than two.

7. The method according to claim 1 or 6, wherein the polyhydric alcohol comprises at least one of ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butylene glycol, 1,6-hexanediol, polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 800, 1,4-cyclohexanediol, 1,4-cyclohexane dimethanol, terephthalyl alcohol, glycerin, trimethylolpropane, pentaerythritol, xylitol and sorbitol.

8. The method according to claim 1, wherein the transesterification is carried out in the presence of a transesterification catalyst.

9. The method according to claim 8, wherein an amount of the transesterification catalyst is in a range from 0.1 wt % to 5 wt % of the inorganic oxyacid ester.

10. The method according to claim 8, wherein the transesterification catalyst is at least one of acidic catalyst and basic catalyst.

11. The method according to claim 10, wherein the acidic catalyst comprises at least one of alcohol-soluble acid, solid acid, aluminum alkoxide, aluminum phenoxide, tetrabutyl stannate, titanium alkoxide, zirconium alkoxide, ethyl antimonite and butyl antimonite; and the basic catalyst comprises at least one of alcohol-soluble base and solid base.

12. The method according to claim 1, wherein conditions for the transesterification are: a reaction temperature ranges from 80 to180° C., and a reaction time ranges from 2 to 10 hours in an inactive atmosphere.

13. The method according to claim 12, wherein the transesterification is performed under stirring condition.

14. The method according to claim 12, wherein the conditions for the transesterification further comprise performing vacuum distillation thereafter.

15. The method according to claim 14, wherein conditions of the vacuum distillation comprise: a vacuum degree ranges from 0.01 to 5 kPa, a vacuum distillation temperature ranges from 70 to 230° C., and a vacuum distillation time ranges from 0.5 to 5 hours.

16. The method according to claim 1, wherein the method comprises following steps: a) mixing inorganic oxyacid ester, polyhydric alcohol and transesterification catalyst, and then performing the transesterification under stirring conditions and in an inactive protection atmosphere, wherein the reaction temperature ranges from 80 to 180° C., and the reaction time ranges from 2 to 10 hours; b) after the reaction in step a), performing vacuum distillation during which the vacuum degree ranges from 0.01 to 5 kPa, the reaction temperature ranges from 170 to 230° C., and the reaction time ranges from 0.5 to 5 hours.

17. The method according to claim 1, wherein an initial decomposition temperature of the polyester polyol is higher than 300° C.

18. The method according to claim 17, wherein an initial decomposition temperature of the polyester polyol reaches 500° C.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0059] FIG. 1 is a thermal analysis diagram of the product synthesized in Example 1 of the present application.

[0060] FIG. 2 is a thermal analysis diagram of the product synthesized in Example 2 of the present application.

DETAILED DESCRIPTION

[0061] The present application will be described in detail below with reference to the examples, but the present application is not limited to these examples.

[0062] Unless otherwise specified, the raw materials in the examples of the present application are all commercially available.

[0063] The analysis methods in the examples of the present application are as follows.

[0064] Thermogravimetric analysis is conducted by TA Q-600 thermogravimetric analyzer produced by TA Instruments. The nitrogen flow rate is 100 ml/min, and the temperature is increased to 700° C. at a temperature rise rate of 10° C./min.

[0065] The conversion rate of the transesterification in the examples of the present application is calculated as follows: according to the number of moles n of the by-product alcohols distilled out during the reaction, the number of groups participating in the transesterification is determined to be n, and the total number of moles of esters in the reaction raw materials is m, and then the conversion rate of the transesterification is n/xm. x depends on the number of alkoxy groups connected to the central atom in the esters.

[0066] According to an embodiment of the present application, the polyester polyol polymer and the method for preparing the same are characterized in that the method includes the following steps: [0067] a) mixing inorganic oxyacid ester, polyhydric alcohol and transesterification catalyst uniformly in a three-necked flask, and performing the transesterification under stirring conditions during which a distillation device is connected to the three-necked flask and nitrogen is passed in the three-necked flask for protection, wherein the reaction temperature ranges from 80 to 180° C., the reaction time ranges from 2 to 10 hours, and the conversion rate of the transesterification ranges from 60% to 80%; [0068] b) after step a), connecting the distillation device to the water pump or oil pump for vacuum distillation to make the transesterification more complete, wherein the vacuum degree is controlled to range from 0.01 to 5 kPa, the reaction temperature ranges from 170 to 230° C., the reaction time ranges from 0.5 to 5 hours, and the conversion rate of the transesterification is greater than 90%.

[0069] Optionally , the formula of the inorganic oxyacid ester in step a) is M(OR)n, wherein M is B, Si, Ge, P, Al, Ti, Fe, Sn, V, Ga, Zr, Cr, Sb, W; R is any one of “C.sub.1 to C.sub.8” alkyl groups; and the inorganic oxyacid ester comprises at least one of trimethyl borate, triethyl borate, tripropyl borate, tributyl borate, tri-n-hexyl borate, triisooctyl borate, trioctyl borate, tetramethoxysilane, tetraethyl orthosilicate, tetrapropyl silicate, tetrabutyl silicate, ethyl orthogermanate, triethyl phosphate, tripropyl phosphate, tributyl phosphate, tri-n-pentyl phosphate, trihexyl phosphate, aluminium ethoxide, aluminum isopropoxide, aluminum n-butoxide, aluminum tert-butoxide, tetraethyl titanate, tetraisopropyl titanate, tetrabutyl titanate, tetrahexyl titanate, tetraisooctyl titanate, tetrabutyl ferrite, tetrabutyl stannate, butyl orthovanadate, gallium ethoxide, tetra-n-propyl zirconate, tetrabutyl zirconate, tert-butyl chromate, ethyl antimonite, butyl antimonate, tungsten ethoxide and tungsten isopropoxide.

[0070] Optionally, the formula of the polyhydric alcohol in step a) is R—(OH).sub.x, wherein x≥2; the polyhydric alcohol comprises at least one of ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butylene glycol, 1,6-hexanediol, polyethylene glycol 200, polyethylene glycol 400, polyethylene glycol 600, polyethylene glycol 800, 1,4-cyclohexanediol, 1,4-cyclohexane dimethanol, terephthalyl alcohol, glycerin, trimethylolpropane, pentaerythritol, xylitol and sorbitol.

[0071] Optionally, in the step a), the molar ratio of the inorganic oxyacid ester to the polyhydric alcohol satisfies: M(OR).sub.n/R—(OH).sub.x=(0.8˜1.2)x/n.

[0072] Optionally, the transesterification catalyst used in the step a) is: a basic catalyst including bases that are easily soluble in alcohol (such as NaOH, KOH, NaOCH.sub.3, organic bases and so on) and various solid base catalysts; and an acidic catalyst including acids that are easily soluble in alcohol (such as sulfuric acid, sulfonic acid and so on) and various solid acidic catalysts, aluminum alkoxide, aluminum phenoxide, tetrabutyl stannate, titanium alkoxide, zirconium alkoxide, ethyl antimonite, butyl antimonite and so on; and the amount of the transesterification catalyst is in a range from 0.1 wt % to 5 wt % of the inorganic oxyacid ester.

[0073] Optionally, the step a) is carried out under nitrogen protection, the reaction temperature thereof ranges from 80 to180° C., and the reaction time thereof ranges from 2 to 10 hours.

[0074] Optionally, the conversion rate of the transesterification in step a) ranges from 60% to 80%.

[0075] Optionally, the step b) is carried out under vacuum distillation conditions, and the vacuum degree thereof ranges from 0.01 to 5 kPa.

[0076] Optionally, in step b), the reaction temperature ranges from 170 to 230° C., and the reaction time ranges from 0.5 to 5 hours.

[0077] Optionally, the conversion rate of the transesterification in step b) is greater than 90%.

EXAMPLE 1

[0078] 10 g 1,3-propanediol, 6.84 g tetraethyl orthosilicate and 5 g tetramethoxysilane are added to a three-necked flask which is connected to a distillation device. 0.12 g concentrated sulfuric acid as catalyst is added dropwise in the three-necked flask under stirring condition. The temperature is heated up to 100° C. under nitrogen protection, and the reaction time is 6 hours. During this process, a large amount of methanol and ethanol are distilled out, and the conversion rate of the transesterification reaction is 75%. Then a vacuum device is connected to distillation device and the transesterification continues under vacuum distillation conditions, wherein the vacuum degree of the reaction system was controlled to be 1 kPa and the temperature was raised to 170° C. After reacting for 1 hour, the transesterification is stopped. After the temperature is naturally cooled to be room temperature, the resulting sample is taken, and the conversion rate of the transesterification is 93%.

EXAMPLE 2

[0079] 5 g ethylene glycol and 8.7 g aluminum ethoxide are added to a three-necked flask which is connected to a distillation device, wherein the aluminum ethoxide is used not only as an inorganic oxyacid salt raw material, but also as a transesterification catalyst. The temperature is heated up to 175° C. under nitrogen protection and stirring condition, and the reaction time is 5 hours. During this process, a large amount of ethanol is distilled out, and the conversion rate of the transesterification reaction is 73%. Then a vacuum device is connected to distillation device and the transesterification continues under vacuum distillation conditions, wherein the vacuum degree of the reaction system was controlled to be 0.1 kPa and the temperature was raised to 210° C. After reacting for 1 hour, the transesterification is stopped. After the temperature is naturally cooled to be room temperature, the resulting sample is taken, and the conversion rate of the transesterification is 92%.

EXAMPLE 3

[0080] 10 g terephthalyl alcohol and 9.07 g tripropyl borate are added to a three-necked flask which is connected to a distillation device. 0.05 g tetrabutyl titanate as catalyst is added dropwise in the three-necked flask under stirring condition. The temperature is heated up to 180° C. under nitrogen protection, and the reaction time is 6 hours. During this process, a large amount of propanol is distilled out, and the conversion rate of the transesterification reaction is 75%. Then a vacuum device is connected to distillation device and the transesterification continues under vacuum distillation conditions, wherein the vacuum degree of the reaction system was controlled to be 1 kPa and the temperature was raised to 230° C. After reacting for 1 hour, the transesterification is stopped. After the temperature is naturally cooled to be room temperature, the resulting sample is taken, and the conversion rate of the transesterification is 93%.

EXAMPLES 4 TO 13

[0081] The specific raw materials, amounts thereof and reaction conditions different from Example 1 are shown in Table 1 below, and the other procedures are the same as those in Example 1.

TABLE-US-00001 TABLE 1 Raw materials, amounts thereof and reaction conditions of Examples 4 to 13 Transesterification Vacuum distillation Example Inorganic oxyacid Reaction Reaction Vacuum Reaction Reaction Number ester Polyhydric alcohol Catalyst temperature time degree temperature time 4 Tetrahexyl titanate, Diethylene glycol, NaOH, 0.03 g  80° C. 10 hours  5 kPa 180° C. 2 hours 0.1 mol 0.2 mol 5 Triethyl phosphate, Polyethylene glycol Na.sub.2CO.sub.3, 0.1 g 100° C. 5 hours 2 kPa 200° C. 0.5 hours   0.2 mol 200, 0.3 mol 6 Tetrabutyl stannate, Trimethylolpropane, Sulfonic acid, 150° C. 2 hours 0.01 kPa   175° C. 5 hours 0.15 mol 0.2 mol 0.06 g 7 Tungsten ethoxide, Xylitol, Tetrabutyl The one in The one in The one in The one in The one in 0.2 mol 0.1 mol stannate, 0.02 g Example 1 Example 1 Example 1 Example 1 Example 1 8 Tetrabutyl ferrite, 1,4-butanediol, Ethyl antimonite, The one in The one in The one in The one in The one in 0.1 mol 0.2 mol 0.04 g Example 1 Example 1 Example 1 Example 1 Example 1 9 Butyl orthovanadate, Glycerol, Butyl antimonite, The one in The one in The one in The one in The one in 0.1 mol 0.2 mol 0.02 g Example 1 Example 1 Example 1 Example 1 Example 1 10 Gallium ethoxide, Pentaerythritol, The one in The one in The one in The one in The one in The one in 0.4 mol 0.3 mol Example 1 Example 1 Example 1 Example 1 Example 1 Example 1 11 Tetra-n-propyl Cyclohexanediol, The one in The one in The one in The one in The one in The one in zirconate, 0.2 mol 0.4 mol Example 1 Example 1 Example 1 Example 1 Example 1 Example 1 12 Tert-Butyl chromate, The one in The one in The one in The one in The one in The one in The one in 0.1 mol Example 1, Example 1 Example 1 Example 1 Example 1 Example 1 Example 1 0.1 mol 13 Ethyl antimonite, The one in The one in The one in The one in The one in The one in The one in 0.4 mol Example 1, Example 1 Example 1 Example 1 Example 1 Example 1 Example 1 0.3 mol

EXAMPLE 5

Thermo Gravimetric Analysis

[0082] The polyester polyol prepared in Example 1 to Example 13 are subjected to thermogravimetric analysis respectively, results of which are typically shown in FIGS. 1 and 2. FIG. 1 shows the thermal analysis curve of the polyester polyol prepared in Example 1. It can be seen from the figure that the initial decomposition temperature of the polyester polyol prepared in Example 1 is 500° C.

[0083] FIG. 2 shows the thermal analysis curve of the polyester polyol prepared in Example 2. It can be seen from the figure that the initial decomposition temperature of the polyester polyol prepared in Example 2 is 500° C.

[0084] The results of the polyester polyol prepared in other examples are similar to the above, and the initial decomposition temperature of the polyester polyol is higher than 300° C.

[0085] The above examples are only illustrative, and do not limit the present application in any form. Any change or modification, made by the skilled in the art based on the technical content disclosed above, without departing from the spirit of the present application, is equivalent example and falls within the scope of the present application.