POLYETHER COMPOSITION, LOW VOC POLYURETHANE FOAM AND PREPARATION METHOD THEREFOR

Abstract

A polyether composition for a polyurethane foam is provided, comprising a polyether polyol and a polyether carbonate polyol that has a primary hydroxyl group molar content of not less than 40 mol %. A method for preparing a polyurethane foam is further provided, comprising the following steps: preparing a mixture by preheating and melting the polyether composition for a polyurethane foam, a foaming agent, a chain extender, a catalyst, a pore-forming agent and a foam stabilizer, and mixing well; cooling the mixture; and performing a polymerization reaction by adding an isocyanate to the cooled mixture and mixing, thus obtaining a polyurethane foam product. The use of the polyether carbonate polyol with the primary hydroxyl group molar content of not less than 40 mol % overcomes the defects of unstable performance of polyurethane and poor mechanical properties of products when the VOC content of the polyurethane foam is reduced by adding additives in the prior art.

Claims

1. A polyether composition for a polyurethane foam, comprising a polyether polyol and a polyether carbonate polyol that has a primary hydroxyl group molar content of not less than 40 mol %.

2. The polyether composition according to claim 1, wherein the polyether carbonate polyol has a primary hydroxyl group molar content of from 50 mol % to 95 mol %.

3. The polyether composition of claim 1, wherein a mass ratio of the polyether carbonate polyol to the polyether polyol is (5-100):(1-95); and preferably, a mass ratio of the polyether carbonate polyol to the polyether polyol is (30-65):(35-70).

4. The polyether composition of claim 1, wherein the polyether carbonate polyol has a molecular weight of from 500 g/mol to 10000 g/mol, a carbonate content of from 5 wt % to 99 wt %, and a functionality degree of from 2 to 8; and preferably, the polyether carbonate polyol has a molecular weight of from 2000 g/mol to 8000 g/mol, a carbonate content of from 20 wt % to 80 wt %, and a functionality degree of from 2 to 6.

5. (canceled)

6. A method for preparing a polyurethane foam, comprising the following steps: preparing a mixture by preheating and melting the polyether composition for a polyurethane foam of claim 1, a foaming agent, a chain extender, a catalyst, a pore-forming agent and a foam stabilizer, and mixing well, cooling the mixture, and performing a polymerization reaction by adding an isocyanate to the cooled mixture and mixing, thus obtaining a polyurethane foam product.

7. The method for preparing a polyurethane foam of claim 6, wherein the isocyanate is selected from one or more of hexamethylene diisocyanate, methylcyclohexyl diisocyanate, dicyclohexylmethane diisocyanate, toluene diisocyanate, methylenediphenyl diisocyanate, p-phenylene diisocyanate, polymethylene polyphenyl polyisocyanate, 3,5-dimethyl 4,4-diphenylmethane diisocyanate, 2,4-ethylbenzene diisocyanate, 3,3-dimethoxy 4,4-diphenylmethane diisocyanate, toluene diisocyanate dimer, isophorone diisocyanate, xylylene diisocyanate, 1,5-naphthalene diisocyanate and tetramethylxylylene diisocynate; preferably, the chain extender is selected from one or more of ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, diethylene glycol, 1,7-heptanediol, 1,8-octanediol, glycerol, trimethylolpropane, 1,4-cyclohexanediol, hydrogenated bisphenol A, diethanolamine, triethanolamine, methyldiethanolamine, 3,3-dichloro-4,4-diphenylmethane, diethyltoluenediamine, 3,5-dimethylthiotoluenediamine, glycerol alpha-monoallyl ether, glycidyl allyl ether and dicumyl peroxide; and preferably, the catalyst is selected from one or more of organotin catalysts and organic amine catalysts.

8. The method for preparing a polyurethane foam of claim 6, wherein said preheating and melting comprise, heating from room temperature to a temperature of 40-100° C. at a constant speed within 0.5 to 1.5 hours while increasing a stirring speed from 80-120 rpm to 800-1200 rpm at a constant speed, and maintaining the stirring at 800 to 1200 rpm for a further 1.5 to 2.5 hours, followed by cooling to room temperature.

9. The method for preparing a polyurethane foam of claim 6, wherein said performing a polymerization reaction comprises carrying out stirring at a speed of 1500 rpm to 2000 rpm for the beginning 5-10 seconds to obtain a reaction mixture, and placing the reaction mixture to a mold to continue the polymerization reaction for 3 min to 20 min at a temperature of 30-100° C.

10. A polyurethane foam prepared by the method of claim 6.

11. The polyether composition according to claim 2, wherein a mass ratio of the polyether carbonate polyol to the polyether polyol is (5-100):(1-95); and preferably, a mass ratio of the polyether carbonate polyol to the polyether polyol is (30-65):(35-70).

12. The polyether composition of claim 2, wherein the polyether carbonate polyol has a molecular weight of from 500 g/mol to 10000 g/mol, a carbonate content of from 5 wt % to 99 wt %, and a functionality degree of from 2 to 8; and preferably, the polyether carbonate polyol has a molecular weight of from 2000 g/mol to 8000 g/mol, a carbonate content of from 20 wt % to 80 wt %, and a functionality degree of from 2 to 6.

13. The polyether composition of claim 3, wherein the polyether carbonate polyol has a molecular weight of from 500 g/mol to 10000 g/mol, a carbonate content of from 5 wt % to 99 wt %, and a functionality degree of from 2 to 8; and preferably, the polyether carbonate polyol has a molecular weight of from 2000 g/mol to 8000 g/mol, a carbonate content of from 20 wt % to 80 wt %, and a functionality degree of from 2 to 6.

14. The method for preparing a polyurethane foam of claim 6, wherein said preheating and melting comprise, heating from room temperature to a temperature of 40-100° C. at a constant speed within 0.5 to 1.5 hours while increasing a stirring speed from 80-120 rpm to 800-1200 rpm at a constant speed, and maintaining the stirring at 800 to 1200 rpm for a further 1.5 to 2.5 hours, followed by cooling to room temperature.

15. The method for preparing a polyurethane foam of claim 6, wherein said performing a polymerization reaction comprises carrying out stirring at a speed of 1500 rpm to 2000 rpm for the beginning 5-10 seconds to obtain a reaction mixture, and placing the reaction mixture to a mold to continue the polymerization reaction for 3 min to 20 min at a temperature of 30-100° C.

16. The method for preparing a polyurethane foam of claim 7, wherein said performing a polymerization reaction comprises carrying out stirring at a speed of 1500 rpm to 2000 rpm for the beginning 5-10 seconds to obtain a reaction mixture, and placing the reaction mixture to a mold to continue the polymerization reaction for 3 min to 20 min at a temperature of 30-100° C.

Description

DETAILED DESCRIPTION OF EMBODIMENTS

[0016] The following examples are provided for a better understanding of the present invention, are not limited to the best embodiment, and do not limit the content and protection scope of the present invention. Any identical or similar product obtained by any person under the enlightenment of the present invention or by combining the features of the present invention and other existing technologies shall fall within the protection scope of the present invention.

[0017] Main reagents of the present invention are as follows:

[0018] Polyether carbonate polyol was provided by Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, and the primary hydroxyl group molar content therein was calculated in mole percentage, mol %. Modified diphenylmethane diisocyanate (modified MDI) was purchased from Yantai Wanhua Polyurethane Co., Ltd. Polyether polyol F2831, polyether polyol 330N and pore-forming agent F-1251 were purchased from Jilin Juyuan Chemical Industry Co., Ltd. Bis(2-dimethylaminoethyl) ether (Niax-Al) catalyst was purchased from Union Carbide Corporation. Organosilicone foam stabilizer B8681 was purchased from Evonik, Germany. Catalyst TEDA33 (a catalyst prepared from 33% of triethylenediamine and 67% of ethylene glycol) was purchased from Tosoh, Japan, etc.

Example 1

[0019] 50 g of dried polyether carbonate polyol (with a molecular weight of 6000 g/mol and a functionality degree of 3) containing 60.0 mol % of primary hydroxyl groups and 55 wt % of carbonate, 50 g of polyether polyol F2831, 0.25 g of catalyst TEDA33, 0.8 g of chain extender diethanolamine, 0.1 g of catalyst Niax-Al, 3 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 3.6 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 50° C. at a constant speed within 1 hour while a stirring speed was slowly increased from 100 rpm to 1000 rpm, the stirring was maintained at 1000 rpm for a further 2 hours, the mixture was cooled to room temperature, 56.21 g of modified MDI was added, the mixture was stirred at a speed of 2000 rpm for 8 s, a mold was preheated to a temperature of 50° C., the mixture was placed to the mold and then reacted at the temperature of 50° C. for 10 min, and the mold was opened to obtain a polyurethane foam product.

Example 2

[0020] 65 g of dried polyether carbonate polyol (with a molecular weight of 4000 g/mol and a functionality degree of 3) containing 45.0 mol % of primary hydroxyl groups and 30 wt % of carbonate, 35 g of polyether polyol 330N, 0.50 g of catalyst TEDA, 0.5 g of chain extender triethanolamine, 0.1 g of catalyst Dabco120, 6 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 4.2 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 100° C. at a constant speed within 0.5 hour while a stirring speed was slowly increased from 80 rpm to 1200 rpm, the mixture was stirred for 1.5 hours and cooled to room temperature, 58 g of hexamethylene diisocyanate was added, the mixture was stirred at a speed of 1500 rpm for 5 s, a mold was preheated to a temperature of 100° C., the mixture was placed to the mold and then reacted at the temperature of 100° C. for 3 min, and the mold was opened to obtain a polyurethane foam product.

Example 3

[0021] 30 g of dried polyether carbonate polyol (with a molecular weight of 2000 g/mol and a functionality degree of 3) containing 95.0 mol % of primary hydroxyl groups and 70 wt % of carbonate, 70 g of polyether polyol 330N, 0.25 g of catalyst TEDA, 0.8 g of chain extender hydrogenated bisphenol A, 0.1 g of catalyst bis(2-dimethylaminoethyl) ether, 3 g of pore-forming agent PUY-603, 0.7 g of foam stabilizer B8462, and 3.0 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 40° C. at a constant speed within 1.5 hours while a stirring speed was slowly increased from 120 rpm to 800 rpm, the mixture was stirred for 2.5 hours and cooled to room temperature, 53 g of xylylene diisocynate was added, the mixture was stirred at a speed of 1800 rpm for 10 s, placed to a mold and then reacted at a temperature of 30° C. for 20 min, and the mold was opened to obtain a polyurethane foam product.

Example 4

[0022] 50 g of dried polyether carbonate polyol (with a molecular weight of 6000 g/mol and a functionality degree of 3) containing 60 mol % of primary hydroxyl groups and 15 wt % of carbonate, 50 g of polyether polyol F2831, 0.25 g of catalyst TEDA33, 0.8 g of chain extender diethanolamine, 0.1 g of catalyst Niax-Al, 3 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 3.6 g of water were mixed well to obtain a mixture, the mixture was quickly heated from room temperature to a temperature of 50° C. within 1 hour while a stirring speed was quickly increased from 100 rpm to 1000 rpm, the stirring was maintained at 1000 rpm for a further 2 hours, the mixture was cooled to room temperature, 56.21 g of modified MDI was added, the mixture was stirred at a speed of 2000 rpm for 8 s, a mold was preheated to a temperature of 50° C., the mixture was placed to the mold and then reacted at the temperature of 50° C. for 10 min, and the mold was opened to obtain a polyurethane foam product.

Example 5

[0023] 50 g of dried polyether carbonate polyol (with a molecular weight of 6000 g/mol and a functionality degree of 3) containing 45 mol % of primary hydroxyl groups and 55 wt % of carbonate, 50 g of polyether polyol F2831, 0.25 g of catalyst TEDA33, 0.8 g of chain extender diethanolamine, 0.1 g of catalyst Niax-Al, 3 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 3.6 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 50° C. at a constant speed within 1 hour while a stirring speed was slowly increased from 100 rpm to 1000 rpm, the stirring was maintained at 1000 rpm for a further 2 hours, the mixture was cooled to room temperature, 56.21 g of modified MDI was added, the mixture was stirred at a speed of 2000 rpm for 8 s, a mold was preheated to a temperature of 50° C., the mixture was placed to the mold and then reacted at the temperature of 50° C. for 10 min, and the mold was opened to obtain a polyurethane foam product.

Example 6

[0024] 15 g of dried polyether carbonate polyol (with a molecular weight of 6000 g/mol and a functionality degree of 3) containing 60 mol % of primary hydroxyl groups and 55 wt % of carbonate, 85 g of polyether polyol F2831, 0.25 g of catalyst TEDA33, 0.8 g of chain extender diethanolamine, 0.1 g of catalyst Niax-Al, 3 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 3.6 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 50° C. at a constant speed within 1 hour while a stirring speed was slowly increased from 100 rpm to 1000 rpm, the stirring was maintained at 1000 rpm for a further 2 hours, the mixture was cooled to room temperature, 56.21 g of modified MDI was added, the mixture was stirred at a speed of 2000 rpm for 8 s, a mold was preheated to a temperature of 50° C., the mixture was placed to the mold and then reacted at the temperature of 50° C. for 10 min, and the mold was opened to obtain a polyurethane foam product.

Comparative Example 1

[0025] 100 g of polyether polyol F2831, 0.25 g of catalyst TEDA33, 0.8 g of chain extender diethanolamine, 0.1 g of catalyst Niax-Al, 3 g of pore-forming agent F-1251, 0.7 g of foam stabilizer B8681, and 3.6 g of water were mixed well to obtain a mixture, the mixture was heated from room temperature to a temperature of 50° C. at a constant speed within 1 hour while a stirring speed was slowly increased from 100 rpm to 1000 rpm, the stirring was maintained at 1000 rpm for a further 2 hours, the mixture was cooled to room temperature, 56.21 g of modified MDI was added, the mixture was stirred at a speed of 2000 rpm for 8 s, a mold was preheated to a temperature of 50° C., the mixture was placed to the mold and then reacted at the temperature of 50° C. for 10 min, and the mold was opened to obtain a polyurethane foam product.

Comparative Example 2

[0026] A polyurethane foam was prepared according to the method disclosed in Example 1 of Chinese Patent Document CN105111397A. Specifically, a method for preparing a low-VOC and high-resilience polyurethane foam composition comprised, preparation of a material A: 42 parts of polyether polyol and 50 parts of polymer polyol were added to a reactor and stirred, then 1 part of silicon foam stabilizer, 1.5 parts of catalyst (bis(2-dimethylaminoethyl) ether), 0.5 part of auxiliary (prepared from manganese dioxide, urea, and ethylenediamine at a mass ratio of 2:5:3), 1 part of cross-linking agent (diethanolamine), and 4 parts of foaming agent (consisting of a mixture of 1.4 parts of cyclopentane and 1.4 parts n-pentane, and 1.2 parts of pure water) were added in order, stirring was carried out at a speed of 100 r/min for 1 hour, and the material A was discharged after test indicators were qualified; preparation of a material B: 70 parts of toluene diisocyanate TDI80/20 was added into a reactor and stirred, 12 parts of liquefied MDI and 18 parts of polymerized MDI were added, indicators were tested after 1 hour, and the material B was discharged after qualified; and a mold was preheated to 60° C., 100 parts of the material A and 60 parts of the material B were quickly stirred well and poured into the mold, the mold was closed, and finally, a polyurethane foam product was released from the mold.

[0027] The polyurethane foam products prepared in Examples 1-6 and Comparative Examples 1-2 were placed for 7 days, and their performances were tested. The density (Kg/m.sup.3) was tested according to ISO845:2006, IDT standards; the compressive hardness (Kpa) was tested according to ISO2439:1997IDT standards; the tensile strength (Kpa) was tested according to ISO1798:2008, IDT standards; the tear strength (N/cm) was tested according to ISO8067:1989IDT standards; the elongation at break (%) was tested according to ISO1798:2008, IDT standards; and VOC gases (benzene, toluene, ethylbenzene, xylene, styrene, formaldehyde, acetaldehyde, and acrolein) were tested according to Q/FC-CD05-001-2013 standards. The results were shown in the following table.

TABLE-US-00001 TABLE 1 Performance test table of polyurethane foam products prepared in Examples 1-6 and Comparative Examples 1-2 Example Example Example Example Example Example Comparative Comparative Test indicator 1 2 3 4 5 6 Example 1 Example 2 Density 45 47.1 46.6 49.2 48.5 46 46.7 45.8 (Kg/m.sup.3) Compressive 8.26 7.21 8.90 7.56 6.50 9.76 6.90 4.32 hardness (Kpa) Tensile strength 191 189 196 194 193 181 180 162 (Kpa) Tear strength 2.91 2.90 2.99 2.71 2.85 2.81 2.78 2.42 (N/cm) Elongation at 135 123 122 105 123 125 98 99 break (%) Benzene ND ND ND ND ND ND 38 ND (μg/m.sup.3) Toluene 6.3 7.2 4.2 10.3 10.25 16.3 110 32 (μg/m.sup.3) Ethylbenzene ND ND ND ND ND ND 35.5 ND (μg/m.sup.3) Xylene (μg/m.sup.3) ND ND ND ND ND ND 97.7 ND Styrene (μg/m.sup.3) ND ND ND ND ND ND 40 21 Formaldehyde 26.2 25.9 23.0 31.2 32.9 26.21 154.8 31.2 (Mg/m.sup.3) Acetaldehyde 18.2 22.1 20.9 30 29.7 33 169 19.1 (Mg/m.sup.3) Acraldehyde ND ND ND ND ND ND ND ND (Mg/m.sup.3)

[0028] It can be seen from Table 1 that, compared to Comparative Examples 1-2, Examples 1-6 of the present invention can significantly reduce the VOC content of polyurethane foams by using the polyether carbonate polyols with a high primary hydroxyl group molar content; in addition, the compressive hardness, tensile strength, tear strength, and elongation at break of the polyurethane foams of the present invention were obviously improved, and the prepared polyurethane foams had the characteristics of low density and high elasticity; moreover, compared to Examples 4-6, Examples 1-3 can further reduce the VOC content and density of the polyurethane foams and improve the tear strength, tensile strength and compressive strength by screening the appropriate primary hydroxyl group molar content, carbonate content and mass ratio of the polyether carbonate polyol to the polyether polyol.

[0029] It is apparent that the above embodiments are merely illustrative of the examples, and are not intended to limit the embodiments. Other variations or modifications of different forms may be made by those of ordinary skill in the art in light of the above description. There is no need and no way to exhaust all of the embodiments. Obvious variations or modifications resulting therefrom are still within the scope of the present invention.