Modified polyol as well as preparation method and application thereof

Abstract

The invention provides modified polyol as well as a preparation method and application thereof. The preparation method comprises the following steps: (1) mixing polyol and alkoxy silane functionalized isocyanate, and reacting to obtain a polyol type compound with a silane modified structure; and (2) mixing the polyhydric alcohol type compound with the silane modified structure in the step (1) with silicon dioxide with active groups on the surface, and reacting to obtain the modified polyhydric alcohol, the active groups in the silicon dioxide with the active groups on the surface comprise hydroxyl. When the modified polyol provided by the invention is applied to preparation of polyurethane foam, the water drying speed, the water absorption speed and the rebound resilience of the polyurethane foam can be improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of polyurethane materials, and particularly relates to a modified polyol and its preparation method and application. Background Art

[0002] Polyurethane foam is a porous polymer material formed by the reaction of polyol and polyisocyanate under the combined action of catalysts, foam stabilizers, blowing agents, etc., and is widely used in various industries, such as clothing padding, upholstered furniture, vehicle seats, etc. The porous structure generated by the foaming of polyurethane makes it have excellent resilience while also having a certain water absorption capacity and can absorb liquids such as sweat. However, traditional polyurethane foam has poor water absorption and rapid drying performance, and it cannot quickly absorb water after contacting with water.

[0003] CN110343229A discloses a polyurethane sponge with good hydrophilic and water filtration properties and its preparation method. The polyurethane sponge with good hydrophilic and water filtration properties includes the following raw material components in parts by weight: polyether polyol, isocyanate, water, catalyst, physical blowing agent, non-ionic surfactant. This technical solution greatly accelerates the speed of water entering the sponge by adding a non-ionic surfactant, but does not solve the problem of achieving rapid drying. In addition, the addition of a monofunctional non-ionic surfactant will cause damage to the cross-linked structure of polyurethane, thereby affecting the mechanical properties of the polyurethane sponge.

[0004] CN107400350A discloses a highly water-absorbent and highly water-retentive polyurethane foam and its preparation method. The highly water-absorbent and highly water-retentive polyurethane foam is composed of the following components mixed in parts by mass: 80 - 120 parts of polyether polyol, 20 - 30 parts of diisocyanate, 0.5 - 55 parts of water-absorbent resin, 20 - 50 parts of blowing agent, 0.2 - 3 parts of surfactant, and 0.2 - 2 parts of catalyst. The highly water-absorbent and highly water-retentive polyurethane foam prepared by this technical solution has the advantages of high water absorption, high resilience, good compression performance, and high stability, but it has high water retention and a slow drying speed.

[0005] In the prior art, there is still a problem that polyurethane foam cannot be quickly dried after absorbing water, which has an adverse impact on human health and comfort when applied in fields such as clothing padding and sports underwear due to the long water-containing time after absorbing water.

[0006] Therefore, it is necessary to develop a modified polyol that can improve the water absorption of polyurethane foam and increase the drying speed. Summary of the Invention

[0007] In view of the deficiencies of the prior art, the purpose of the present invention is to provide a modified polyol, a preparation method and an application thereof. The modified polyol can be applied to the preparation of polyurethane foam. By using the modified polyol, the drying speed, water absorption speed and resilience of the polyurethane foam to water can be improved.

[0008] To achieve this purpose, the present invention adopts the following technical solutions:

[0009] In the first aspect, the present invention provides a preparation method of a modified polyol, and the preparation method includes the following steps:

[0010] (1) Mix a polyol and an alkoxysilane-functionalized isocyanate, and react to obtain a polyol-type compound with a silane-modified structure;

[0011] (2) Mix the polyol-type compound with a silane-modified structure obtained in step (1) and silica with active groups on the surface, and react to obtain the modified polyol;

[0012] The active groups in the silica with active groups on the surface include hydroxyl groups.

[0013] In the present invention, a polyol-type compound with a silane-modified structure is prepared by reacting a polyol and an alkoxysilane-functionalized isocyanate, and then reacting with silica with active groups on the surface. The hydroxyl groups in the active groups have reactivity with siloxane groups to form a modified polyol, and the modified polyol can be applied to the preparation of polyurethane foam. By using the modified polyol, the water absorption speed and the drying speed of the prepared polyurethane foam to water are both improved, solving the problems that traditional polyurethane foam cannot absorb water quickly and dry quickly, etc.; the modified polyol also improves the resilience of the polyurethane foam, and can bring a comfortable feeling to the wearer when applied to fields such as clothing padding and sports underwear.

[0014] Preferably, the number average molecular weight of the polyol is 800-12000 g / mol (such as 1200 g / mol, 2400 g / mol, 3600 g / mol, 4800 g / mol, 5000 g / mol, 6200 g / mol, 7400 g / mol, 8600 g / mol, 9800 g / mol or 11000 g / mol, etc.), and more preferably 3000-6000 g / mol.

[0015] Preferably, the functionality of the polyol ≥2, such as 3, 4, 5 or 6, etc.

[0016] Preferably, the polyol includes any one or at least two combinations of vinyl polymer grafted polyether polyol (commonly known as polymer polyol, abbreviated as POP), polyether polyol or polyester polyol.

[0017] Preferably, the content of the vinyl polymer in the vinyl polymer grafted polyether polyol is 10 wt% to 50 wt%, such as 15 wt%, 20 wt%, 25 wt%, 30 wt%, 35 wt%, 40 wt% or 45 wt%, etc.

[0018] Preferably, the vinyl polymer in the vinyl polymer grafted polyether polyol includes acrylonitrile-styrene copolymer.

[0019] Preferably, the polyester polyol includes polycarbonate polyol.

[0020] Preferably, the alkoxysilane-functionalized isocyanate has a structure shown in the following formula 1:

[0021]

[0022] Preferably, in formula 1, X is selected from any one of substituted or unsubstituted C1-C18 (such as C2, C4, C6, C8, C10, C12, C14 or C16, etc.) linear or branched alkylene groups, substituted or unsubstituted C3-C18 (such as C4, C6, C8, C10, C12, C14 or C16, etc.) cycloalkylene groups, substituted or unsubstituted C2-C18 non-aromatic heterocyclic groups, substituted or unsubstituted C6-C18 (such as C8, C10, C12, C14 or C16, etc.) arylene groups, and substituted or unsubstituted C3-C18 (such as C4, C6, C8, C10, C12, C14 or C16, etc.) heteroarylene groups.

[0023] Preferably, in formula 1, the R 1 , R 2 and R 3 are each independently selected from substituted or unsubstituted C1-C18 (such as C2, C4, C6, C8, C10, C12, C14 or C16, etc.) alkyl groups, substituted or unsubstituted C6-C18 (such as C8, C10, C12, C14 or C16, etc.) aryl groups, substituted or unsubstituted C3-C18 (such as C4, C6, C8, C10, C12, C14 or C16, etc.) cycloalkyl groups, and substituted or unsubstituted C1-C18 (such as C2, C4, C6, C8, C10, C12, C14 or C16, etc.) alkoxy groups. At least one of R 1 , R 2 and R 3 is selected from substituted or unsubstituted C1-C18 alkoxy groups.

[0024] Preferably, when the above groups have substituents, the substituents include any one or at least two combinations of C1-C10 (such as C2, C3, C4, C5, C6, C7, C8 or C9, etc.) alkyl, C6-C12 (such as C7, C8, C9, C10 or C11, etc.) aryl or C4-C10 (such as C5, C6, C7, C8 or C9, etc.) heteroaryl.

[0025] Preferably, in Formula 1, the R 1 , R 2 and R 3 each independently selected from any one of substituted or unsubstituted C1-C18 (such as C2, C4, C6, C8, C10, C12, C14 or C16, etc.) alkoxy groups.

[0026] Preferably, the X is selected from any one of methylene, ethylene, propylene or butylene.

[0027] Preferably, the R 1 , R 2 and R 3 each independently selected from any one of methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy or butoxy, and at least one of R 1 , R 2 and R 3 is selected from any one of methoxy, ethoxy, propoxy or butoxy.

[0028] Preferably, the alkoxysilane-functionalized isocyanate includes any one or at least two combinations of isocyanatopropyltrimethoxysilane, isocyanatopropyltriethoxysilane, isocyanatopropyltripropoxysilane, isocyanatopropyltributoxysilane, isocyanatomethyltrimethoxysilane, isocyanatopropylmethyldiethoxysilane or isocyanatopropylmethyldimethoxysilane.

[0029] Preferably, the silica with active groups on the surface includes fumed silica.

[0030] Preferably, the active groups in the silica with active groups on the surface further include amino and / or carboxyl groups.

[0031] Preferably, before the mixing in step (1), there is also a step of dehydrating the polyol.

[0032] Preferably, in step (1), the molar ratio of the hydroxyl group in the polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate is (1-10):1 (such as 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1 or 9:1, etc.), and more preferably (2-3):1.

[0033] In the present invention, the molar ratio of the hydroxyl groups in the polyol to the isocyanate groups in the alkoxysilane-functionalized isocyanate in step (1) is preferably (2 - 3):1. If the molar ratio is too large, the proportion of isocyanate groups in the modified polyol is too small, and the amount of alkoxysilane-functionalized isocyanate and silica with active groups on the surface introduced onto the modified polyol is small, resulting in limited improvement in the properties of the prepared polyurethane foam and relatively low drying and water absorption rates of water. If the molar ratio is too small, the proportion of isocyanate groups in the modified polyol is too large, and the prepared modified polyol undergoes excessive self-polymerization and has a high viscosity, making it difficult to achieve uniform mixing with other components during the preparation of polyurethane foam, resulting in limited improvement in the properties of the prepared polyurethane foam and relatively low drying and water absorption rates of water.

[0034] Preferably, the mass ratio of the polyol in step (1) to the silica with active groups in step (2) is 10:(0.2 - 20), such as 100:1, 100:3, 100:5, 100:7, 100:9, 100:11, 100:13, 100:15, 100:17, or 100:19, etc., and more preferably 100:(1 - 10).

[0035] In the present invention, the mass ratio of the polyol in step (1) to the silica with active groups in step (2) is preferably 100:(1 - 10). If the mass ratio is too large, the amount of silica with active groups introduced onto the modified polyol is small, resulting in limited improvement in the properties of the prepared polyurethane foam and relatively low drying and water absorption rates of water. If the mass ratio is too small, the prepared modified polyol has a high viscosity, making it difficult to achieve uniform mixing with other components during the preparation of polyurethane foam, resulting in difficult operation and limited improvement in the properties of the prepared polyurethane foam and relatively low drying and water absorption rates of water.

[0036] Preferably, the mixing in step (1) further includes mixing with a catalyst.

[0037] Preferably, the catalyst includes an organotin catalyst.

[0038] Preferably, the organotin catalyst includes stannous octoate and / or dibutyltin dilaurate.

[0039] Preferably, the mass ratio of the catalyst to the polyol is 100:(0.04 - 0.08), such as 100:0.045, 100:0.05, 100:0.055, 100:0.06, 100:0.065, 100:0.07, or 100:0.075, etc.

[0040] Preferably, the reactions in steps (1) and (2) are carried out under an inert atmosphere.

[0041] Preferably, the temperature of the reaction in step (1) is 45 to 70 °C (such as 48 °C, 51 °C, 54 °C, 57 °C, 60 °C, 63 °C, 65 °C or 68 °C, etc.), and the reaction time is 2.0 to 5.0 h (such as 2.3 h, 2.6 h, 2.9 h, 3.2 h, 3.5 h, 3.8 h, 4.1 h, 4.4 h or 4.7 h, etc.).

[0042] Preferably, the temperature of the reaction in step (2) is 40 to 65 °C (such as 43 °C, 46 °C, 49 °C, 52 °C, 55 °C, 58 °C, 61 °C or 64 °C, etc.), and the reaction time is 0.5 to 1.5 h (such as 0.6 h, 0.7 h, 0.8 h, 0.9 h, 1.0 h, 1.1 h, 1.2 h, 1.3 h or 1.4 h, etc.).

[0043] In a second aspect, the present invention provides a modified polyol, which is prepared by the preparation method as described in the first aspect.

[0044] In a third aspect, the present invention provides a polyurethane composition, which comprises component A and component B. Component A comprises the modified polyol as described in the second aspect, and component B comprises a diisocyanate.

[0045] Preferably, component A comprises the following components by weight: 10 to 60 parts of the modified polyol as described in the second aspect (such as 15 parts, 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts or 55 parts, etc.), 0 to 60 parts of a polyether polyol (such as 10 parts, 20 parts, 30 parts, 40 parts, 50 parts, etc.), 10 to 40 parts of a vinyl polymer grafted polyether polyol (such as 15 parts, 20 parts, 25 parts, 30 parts or 35 parts, etc.), 2.5 to 3.5 parts of a foaming agent (such as 2.6 parts, 2.7 parts, 2.8 parts, 2.9 parts, 3.0 parts, 3.1 parts, 3.2 parts, 3.3 parts or 3.4 parts, etc.), 0.4 to 0.8 parts of a foam stabilizer (such as 0.45 parts, 0.5 parts, 0.55 parts, 0.6 parts, 0.65 parts, 0.7 parts or 0.75 parts, etc.) and 0.3 to 0.8 parts of a catalyst (such as 0.4 parts, 0.5 parts, 0.6 parts or 0.7 parts, etc.).

[0046] Preferably, the foaming agent comprises water.

[0047] Preferably, the water comprises deionized water.

[0048] Preferably, the foam stabilizer comprises a modified silicone oil.

[0049] Preferably, the catalyst in the component A includes any one or a combination of at least two of stannous octoate, bis(dimethylaminoethyl) ether or triethylenediamine, and is further preferably a combination of stannous octoate, bis(dimethylaminoethyl) ether and triethylenediamine.

[0050] Preferably, the diisocyanate in the component B includes toluene diisocyanate.

[0051] Preferably, the polyurethane composition includes the following components by weight: 95 to 105 parts (such as 96 parts, 97 parts, 98 parts, 99 parts, 100 parts, 101 parts, 102 parts, 103 parts or 104 parts, etc.) of component A and 35 to 40 parts (such as 35.5 parts, 36 parts, 36.5 parts, 37 parts, 37.5 parts, 38 parts, 38.5 parts, 39 parts or 39.5 parts, etc.) of component B.

[0052] Fourthly, the present invention provides a polyurethane foam, which is obtained by foaming and molding the polyurethane composition as described in the third aspect.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] In the present invention, a polyol-type compound with a silane-modified structure is prepared by reacting a polyol with an alkoxysilane-functionalized isocyanate, and then reacting with silica having active groups on the surface to prepare a modified polyol. By using the modified polyol of the present invention to prepare polyurethane foam, the water absorption rate and the drying rate of water of the polyurethane foam are effectively improved, and problems such as the inability of traditional polyurethane foam to quickly absorb water and quickly dry are solved. The use of the modified polyol also improves the resilience of the polyurethane foam. Detailed Embodiments

[0055] The technical solutions of the present invention will be further described below through specific embodiments. Those skilled in the art should understand that the embodiments are only for helping to understand the present invention and should not be regarded as specific limitations on the present invention.

[0056] The sources of some components in the following examples and comparative examples are as follows:

[0057] (1) Polyether polyol

[0058] Polyether polyol A: The functionality is 3, the number average molecular weight is 6000 g / mol, the manufacturer is Hongwei Chemical Industry, and the product number is PHL-3600;

[0059] Polyether polyol B: The functionality is 3, the number average molecular weight is 800 g / mol, the manufacturer is Hongwei Chemical Industry, and the product number is PHL-3080;

[0060] Polyether polyol C: functionality is 3, number average molecular weight is 1000 g / mol, manufacturer is Hongwei Chemical Industry, grade is PHL-3100;

[0061] Polyether polyol D: functionality is 3, number average molecular weight is 12000 g / mol, manufacturer is Hongwei Chemical Industry, grade is PHL-3120;

[0062] Polyether polyol E: functionality is 4, number average molecular weight is 8000 g / mol, manufacturer is Hongwei Chemical Industry, grade is PHL-4800;

[0063] Polyether polyol F: functionality is 6, number average molecular weight is 6000 g / mol, manufacturer is Hongwei Chemical Industry, grade is PHL-6600;

[0064] Polyether polyol G: functionality 3, number average molecular weight is 6000 g / mol, manufacturer is Juyuan Chemistry, grade is P-2831.

[0065] (2) Vinyl polymer grafted polyether polyol

[0066] POP-1: Vinyl polymer grafted polyether polyol, functionality is 3, number average molecular weight is 6000 g / mol, where the mass percentage of acrylonitrile-styrene copolymer is 40% - 45%, solid content is 45%; manufacturer is Hongwei Chemical Industry, grade PPL-3460;

[0067] POP-2: Vinyl polymer grafted polyether polyol, functionality is 3, number average molecular weight is 3600 g / mol, where the mass percentage of acrylonitrile-styrene copolymer is 40% - 45%, solid content is 45%; manufacturer is Hongwei Chemical Industry, grade PPL-3436;

[0068] POP-3: Vinyl polymer grafted polyether polyol, functionality is 3, number average molecular weight is 4800 g / mol, where the mass percentage of acrylonitrile-styrene copolymer is 40% - 45%, solid content is 45%; manufacturer is Hongwei Chemical Industry, grade PPL-3448;

[0069] POP-4: Vinyl polymer grafted polyether polyol, functionality is 3, where the mass percentage of the alkenyl polymer with acrylonitrile-styrene as the main chain structure is 43% - 47%, manufacturer is Longhua Chemical, grade is LHS-100.

[0070] (3) Polyester polyol, functionality is 2, number average molecular weight is 6000 g / mol, manufacturer is Hongwei Chemical Industry, grade is PEP-2600.

[0071] (4) Alkoxysilane-functionalized isocyanate

[0072] Propyl triethoxysilane isocyanate, manufactured by Titan Technology, reagent grade;

[0073] Isocyanatepropyltrimethoxysilane, manufactured by Titan Technology, reagent grade;

[0074] Isocyanatepropyltripropoxysilane, manufactured by CoFormula, reagent grade;

[0075] Isocyanate propylmethyldimethoxysilane, manufacturer: Titan Technology, reagent grade;

[0076] Isocyanate propylmethyldiethoxysilane, manufactured by Titan Technology, reagent grade;

[0077] Methyltrimethoxysilane isocyanate, manufactured by CoFormula, reagent grade.

[0078] (5) Silica with active groups on the surface: Fumed silica M-5, manufactured by Cabot Corporation, USA, industrial grade.

[0079] (6) Catalyst

[0080] Stannous octoate: catalyst T-9, manufactured by Aladdin, reagent grade;

[0081] Bis(dimethylamino)ethyl ether: Catalyst A-1, manufactured by Momentive Chemical, industrial grade;

[0082] Triethylenediamine: Catalyst A-33, manufactured by Momentive Chemical, industrial grade.

[0083] (7) Toluene diisocyanate, brand name TDI80, manufacturer: Wanhua Chemical, industrial grade.

[0084] (8) Modified silicone oil: polyether modified silicone, brand name M-6698F2, manufacturer: Meside, industrial grade.

[0085] The sources of some experimental instruments and equipment used in the embodiments and comparative examples are as follows:

[0086] Overhung mechanical stirrer, model Eurostar 60control, manufacturer IKA;

[0087] Constant temperature water bath, model HH-1, manufactured by Guohua;

[0088] Diaphragm vacuum pump, model VACSTAR control, manufacturer IKA;

[0089] High-speed disperser, model SFJ-750, manufactured by Modern Environment.

[0090] Example 1

[0091] This example provides a modified polyol, its preparation method, and a polyurethane foam. The preparation method of the modified polyol is as follows:

[0092] (1) Add 250 g of polyol (polyether polyol A) to a 500 mL four-necked flask. Using a cantilever mechanical stirrer at a stirring speed of 100 rpm, introduce nitrogen for bubbling for 0.5 h, and then stop bubbling. Under a nitrogen atmosphere, use a constant temperature water bath to heat the polyether polyol to 120 °C, then stop nitrogen input. Use a diaphragm vacuum pump to reduce the pressure of the reaction system to 0.001 MPa and carry out vacuum dehydration for 2.0 h;

[0093] Under a nitrogen atmosphere, after cooling the above polyol system to 60 °C, inject 10.29 g of alkoxysilane-functionalized isocyanate (isocyanatopropyltriethoxysilane), mix at a stirring speed of 100 rpm for 15 min, inject 0.18 g of catalyst (catalyst T-9) under a nitrogen atmosphere, and carry out a stirring reaction at 60 °C and 100 rpm for 4.0 h. Analyze by infrared until the isocyanate group disappears to obtain a polyol-type compound with a silane-modified structure.

[0094] (2) Add 5.25 g of fumed silica M-5 to the polyol-type compound with a silane-modified structure prepared in step (1). Under a nitrogen atmosphere at 60 °C, carry out a stirring reaction at 100 rpm for 1.0 h, cool to 25 °C and then discharge. Store it sealed under a nitrogen atmosphere to obtain the modified polyol.

[0095] The molar ratio of the hydroxyl group in the above polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate is 3:1.

[0096] The mass ratio of the above polyol to fumed silica M-5 is 100:2.1.

[0097] The polyurethane foam is prepared by the following method:

[0098] Add 20 parts by weight of the above modified polyol, 40 parts by weight of polyether polyol (polyether polyol G, P-2831), 40 parts by weight of vinyl polymer grafted polyether polyol (POP-4, LHS-100), 3.3 parts by weight of blowing agent (deionized water), 0.7 parts by weight of foam stabilizer (polyether-modified silicone, M-6698F2), 0.1 parts by weight of catalyst A-1, 0.15 parts by weight of catalyst A-33, and 0.15 parts by weight of catalyst T-9 into a beaker. Use a high-speed disperser to stir at 2000 r / min for 20 min to make it evenly mixed, and let it stand at 20 °C for 4 h to obtain the polyurethane foaming component;

[0099] Pour the above polyurethane foaming components into a 2L plastic measuring cup, and add 38.65 parts by weight of Component B (toluene diisocyanate) to it at one time. Stir vigorously with a high-speed disperser at a speed of 2500 r / min for 8 s, then pour the mixture into a 200mm×200mm×200mm square mold. After free foaming at room temperature of 20°C for 10 min, take it out from the square mold and place it in a fume hood for curing at room temperature of 20°C for 72 h to obtain the polyurethane foam.

[0100] Example 2

[0101] This example provides a modified polyol, its preparation method and polyurethane foam. The preparation method of the modified polyol is as follows:

[0102] (1) Add 250 g of polyol (polyether polyol A) to a 500 mL four-necked flask. Use a cantilever mechanical stirrer to stir at a speed of 100 rpm, and introduce nitrogen for bubbling for 0.5 h, then stop bubbling. Under a nitrogen atmosphere, use a constant temperature water bath to heat the polyether polyol to 120°C, then stop nitrogen input, and use a diaphragm vacuum pump to reduce the pressure of the reaction system to 0.001 MPa for vacuum dehydration for 2.0 h;

[0103] Under a nitrogen atmosphere, after cooling the above polyol system to 60°C, inject 10.29 g of alkoxysilane-functionalized isocyanate (isocyanatopropyltriethoxysilane), mix at a stirring speed of 100 rpm for 15 min, inject 0.2 g of catalyst (catalyst T-9) under a nitrogen atmosphere, and react at 45°C and 100 rpm for 5.0 h under a nitrogen atmosphere. Analyze by infrared until the isocyanate group disappears to obtain a polyol-type compound with a silane-modified structure.

[0104] (2) Add 2.5 g of fumed silica M-5 to the polyol-type compound with a silane-modified structure prepared in step (1). Stir and react at 65°C and 100 rpm for 0.5 h under a nitrogen atmosphere, cool to 25°C and then discharge, and store it sealed under a nitrogen atmosphere to obtain the modified polyol.

[0105] The molar ratio of the hydroxyl group in the above polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate is 3:1.

[0106] The mass ratio of the above polyol to fumed silica M-5 is 100:1.

[0107] The polyurethane foam is prepared by the following method:

[0108] Add 15 parts by weight of the above-mentioned modified polyol, 60 parts by weight of polyether polyol (polyether polyol G, P-2831), 25 parts by weight of vinyl polymer grafted polyether polyol (POP-4, LHS-100), 3.5 parts by weight of foaming agent (deionized water), 0.7 parts by weight of foam stabilizer (polyether-modified silicone, M-6698F2), 0.2 parts by weight of catalyst A-1, 0.4 parts by weight of catalyst A-33, and 0.15 parts by weight of catalyst T-9 into a beaker. Stir with a high-speed disperser at 2000 r / min for 20 min to mix evenly, and let it stand at 20 °C for 4 h to obtain the polyurethane foaming component;

[0109] Pour the above-mentioned polyurethane foaming component into a 2 L plastic measuring cup, and add 38.12 parts by weight of component B (toluene diisocyanate) to it at one time. Stir vigorously with a high-speed disperser at a speed of 2500 r / min for 8 s, then pour the mixture into a 200 mm×200 mm×200 mm square mold. Let it freely foam at room temperature of 20 °C for 10 min, then take it out of the square mold and place it in a fume hood to cure at room temperature of 20 °C for 72 h to obtain the polyurethane foam.

[0110] Example 3

[0111] This example provides a modified polyol, its preparation method, and polyurethane foam. The preparation method of the modified polyol is as follows:

[0112] (1) Add 250 g of polyol (polyether polyol A) to a 500 mL four-necked flask. Use a cantilever mechanical stirrer to stir at a speed of 100 rpm, and introduce nitrogen for bubbling for 0.5 h, then stop bubbling. Under a nitrogen atmosphere, use a constant temperature water bath to heat the polyether polyol to 120 °C, then stop nitrogen input, and use a diaphragm vacuum pump to reduce the pressure of the reaction system to 0.001 MPa for vacuum dehydration for 2.0 h;

[0113] Under a nitrogen atmosphere, after cooling the above polyol system to 60 °C, inject 10.29 g of alkoxysilane-functionalized isocyanate (isocyanatopropyltriethoxysilane), mix at a stirring speed of 100 rpm for 15 min, inject 0.1 g of catalyst (catalyst T-9) under a nitrogen atmosphere, and react at 70 °C and 100 rpm for 2.0 h. Analyze by infrared until the isocyanate group disappears to obtain a polyol-type compound with a silane-modified structure.

[0114] (2) Add 510 g of fumed silica M to the polyol-type compound with a silane-modified structure prepared in step (1). React at 40 °C and 100 rpm for 1.5 h under a nitrogen atmosphere, cool to 25 °C and then discharge, and store it sealed under a nitrogen atmosphere to obtain the modified polyol.

[0115] The molar ratio of the hydroxyl groups in the above polyol to the isocyanate groups in the alkoxysilane-functionalized isocyanate is 3:1.

[0116] The mass ratio of the above polyol to fumed silica M-5 is 100:4.

[0117] The polyurethane foam is prepared by the following method:

[0118] Put 30 parts by weight of the above modified polyol, 50 parts by weight of polyether polyol (polyether polyol G, P-2831), 20 parts by weight of vinyl polymer grafted polyether polyol (POP-4, LHS-100), 2.5 parts by weight of foaming agent (deionized water), 0.6 part by weight of foam stabilizer (polyether-modified silicone, M-6698F2), 0.1 part by weight of catalyst A-1, 0.3 part by weight of catalyst A-33 and 0.15 part by weight of catalyst T-9 into a beaker, and stir with a high-speed disperser at 2000 r / min for 20 min to mix evenly. Let it stand at 20 °C for 4 h to obtain the polyurethane foaming component;

[0119] Pour the above polyurethane foaming component into a 2 L plastic measuring cup, add 38.65 parts by weight of component B (toluene diisocyanate) to it at one time, stir vigorously with a high-speed disperser at a speed of 2500 r / min for 8 s, then pour the mixture into a 200 mm × 200 mm × 200 mm square mold. After free foaming at room temperature of 20 °C for 10 min, take it out from the square mold and place it in a fume hood. Cure at room temperature of 20 °C for 72 h to obtain the polyurethane foam.

[0120] Examples 4 to 23

[0121] Examples 4 to 23 respectively provide a modified polyol, its preparation method and polyurethane foam. The difference from Example 1 is the raw materials, contents and reaction conditions added in the preparation method of the modified polyol. See Table 1 for details.

[0122] Table 1

[0123]

[0124] Example 24

[0125] This example provides a modified polyol, its preparation method and polyurethane foam. The difference from Example 1 is that in the preparation of the polyurethane foam, the weight fraction of the modified polyol is adjusted to 40 parts, and the weight fraction of the polyether polyol (polyether polyol G, P-2831) is adjusted to 20 parts, and other conditions are the same as those in Example 1.

[0126] Example 25

[0127] This embodiment provides a modified polyol, its preparation method, and a polyurethane foam. The difference from Embodiment 1 is that in the preparation of the polyurethane foam, the weight fraction of the modified polyol is adjusted to 60 parts, and no polyether polyol (polyether polyol G, P-2831) is added. Other conditions are the same as those in Embodiment 1.

[0128] Comparative Example 1

[0129] This comparative example provides a polyurethane foam. The difference from Embodiment 1 is only that in the preparation of the polyurethane foam, no modified polyol is added, and the weight fraction of the polyether polyol (polyether polyol G, P-2831) is adjusted to 60 parts. Other conditions are the same as those in Embodiment 1.

[0130] Comparative Example 2

[0131] This comparative example provides a polyurethane foam. The difference from Embodiment 1 is only that polyether polyol A and isocyanatopropyltriethoxysilane are physically stirred and mixed at 20°C, and the molar ratio of the hydroxyl groups in polyether polyol A to the isocyanate groups in isocyanatopropyltriethoxysilane is 3:1 to obtain a mixture;

[0132] In the preparation of the polyurethane foam, the modified polyol is replaced with the above mixture of the same mass. Other conditions are the same as those in Embodiment 1.

[0133] Comparative Example 3

[0134] This comparative example provides a polyurethane foam. The difference from Embodiment 1 is only that polyether polyol A and fumed silica M-5 are physically stirred and mixed at 20°C, and the mass ratio of polyether polyol A to fumed silica M-5 is 100:2.1 to obtain a mixture;

[0135] In the preparation of the polyurethane foam, the modified polyol is replaced with the above mixture of the same mass. Other conditions are the same as those in Embodiment 1.

[0136] Comparative Example 4

[0137] This comparative example provides a polyurethane foam. The difference from Embodiment 1 is only that polyether polyol A, isocyanatopropyltriethoxysilane, and fumed silica M-5 are physically stirred and mixed at 20°C, the molar ratio of the hydroxyl groups in polyether polyol A to the isocyanate groups in isocyanatopropyltriethoxysilane is 3:1, and the mass ratio of polyether polyol A to fumed silica M-5 is 100:2.1 to obtain a mixture;

[0138] In the preparation of the polyurethane foam, the modified polyol is replaced with the above mixture of the same mass. Other conditions are the same as those in Embodiment 1.

[0139] Comparative Example 5

[0140] This comparative example provides a polyurethane foam, the difference from Example 1 being only that the preparation method of the modified polyol does not include step (2), and a polyol-type compound with a silane-modified structure is prepared;

[0141] In the preparation of the polyurethane foam, the modified polyol was replaced with a polyol-type compound having a silane-modified structure of the same mass, and other conditions were the same as in Example 1.

[0142] Comparative Example 6

[0143] This comparative example provides a polyurethane foam, the difference from Example 1 being only that the preparation method of the modified polyol does not include step (2), and a polyol-type compound with a silane-modified structure is prepared;

[0144] 260.47 g of a polyol-type compound having a silane-modified structure and 5.25 g of fumed silica M-5 were physically stirred and mixed at 20 °C to obtain a mixture;

[0145] In the preparation of the polyurethane foam, the modified polyol was replaced with the above mixture of the same mass, and other conditions were the same as in Example 1.

[0146] The polyurethane foams provided in Examples 1 to 25 and Comparative Examples 1 to 6 were subjected to the following performance tests.

[0147] (1) Measurement of water absorption rate: The polyurethane foam was cut into a cube specimen of 5.0 cm × 5.0 cm × 5.0 cm, and one of them was taken and its initial mass M 0 was weighed. It was slowly placed in a flat-bottomed cylindrical container with an inner diameter of 18.0 cm and containing 5.0 cm of deionized water (the specimen floated on the water surface). Every 15 minutes, the specimen was taken out and the residual water on the surface layer of the specimen was blotted with blotting paper, and the mass of the specimen was weighed and recorded as M t . The specimen was put back into the flat-bottomed cylindrical container containing water. When the test time reached 120 minutes (t = 120 min), the mass of the specimen at this moment (M 120 ) was weighed, and then the measurement of the water absorption rate was stopped.

[0148] The formula for calculating the water absorption rate (T-Wab) of the polyurethane foam at t = 120 min is:

[0149] T-Wab = [(M 120 - M 0 ) / M 0 × 100%;

[0150] After cutting the same polyurethane foam, take 3 cubic specimens of 5.0 cm × 5.0 cm × 5.0 cm, and measure the water absorption rate of the polyurethane foam at the moment of t = 120 min respectively to obtain (T-Wab) 1 、(T-Wab) 2 and (T-Wab) 3 , calculate the average water absorption rate (T-Wab) ave at the moment of t = 120 min as follows:

[0151] (T-Wab) ave = [(T-Wab) 1 + (T-Wab) 2 + (T-Wab) 3 / 3;

[0152] Compare the (T-Wab) ave values of different polyurethane foam specimens at the same moment of t = 120 min, and the water absorption rates can be compared. The higher the (T-Wab) ave value, the faster the water absorption rate.

[0153] (2) Measurement of the drying rate (water loss rate) of water: Cut the polyurethane foam into cubic specimens of 5.0 cm × 5.0 cm × 5.0 cm, take 1 of them, weigh its initial mass M 0 , slowly place it in a flat-bottomed cylindrical container with an inner diameter of 18.0 cm and containing 5.0 cm high deionized water (the specimen floats on the water surface). After 120 minutes of testing time, take out the specimen and absorb the residual water on the surface of the specimen with absorbent paper, and record the mass of the specimen as M 120 . Place the specimen on a stainless steel wire mesh with a grid spacing of 2 cm and a diameter of 0.1 cm. Place the stainless steel wire mesh with the specimen in an environment with a temperature of 22.1 °C, a humidity of 32.5% (relative humidity), and a wind speed of 0.5 m / s for drying rate testing. Take out the specimen every 30 minutes and record the mass of the specimen as ML t . When the testing time reaches 120 minutes (t = 120 min), weigh the mass of the specimen at this moment (ML 120 ), and then stop measuring the drying rate.

[0154] The formula for calculating the drying rate (T-Wlo) of the polyurethane foam at the moment of t = 120 min is:

[0155] T-Wlo = [(M 120 - ML 120 ) / (M 120 - M 0 )] × 100%;

[0156] After cutting the same polyurethane foam, take 3 cubic specimens of 5.0 cm × 5.0 cm × 5.0 cm and conduct the above measurements respectively to obtain (T-Wlo) 1 、(T-Wlo) 2 and (T-Wlo) 3 . Calculate the average drying rate (T-Wlo) ave of the polyurethane foam at t = 120 min as follows:

[0157] (T-Wlo) ave = [(T-Wlo) 1 + (T-Wlo) 2 + (T-Wlo) 3 / 3;

[0158] Compare the (T-Wlo) ave values of different polyurethane foam specimens at the same t = 120 min. Then the drying speed can be compared. The higher the (T-Wlo) ave value, the faster the drying speed, that is, the better the rapid drying performance.

[0159] (3) Rebound performance: Refer to GB / T 6670-2008 "Determination of rebound performance of flexible cellular polymeric materials by the falling ball method" to conduct the falling ball method rebound performance test.

[0160] Cut the polyurethane foam into specimens of 10.0 cm × 10.0 cm × 5.0 cm. Take 1 of them and use a universal material testing machine (model 34TM-30, manufacturer Instron) for preloading: Compress it to 80% (4.0 cm) of the original thickness at a speed of 0.5 mm / s, retract the pressure clamp to the starting position. After the specimen elastically recovers to the starting height, compress it again to 80% (4.0 cm) of the original thickness at a speed of 0.5 mm / s, and retract the pressure clamp to the starting position (a total of 2 compressions). After the compressed specimen is left standing for 10 min, immediately conduct the falling ball rebound performance test.

[0161] Falling ball rebound performance test: Place the specimen on the reference surface of the visual falling ball rebound tester. Vertically fix a transparent measuring tube with a length of 600 mm and an inner diameter of 50 mm above the specimen. Confirm that there is a light contact between the tube and the specimen without causing any visible pressure. Confirm that the zero rebound position is 16 mm above the specimen surface. Place a 16.9 g steel ball (diameter 16 mm) on the release device and then release the steel ball. Record the integer value h of the maximum rebound height. The calculation method of the falling ball percentage rebound value R is:

[0162] R = (h / h max ) × 100%;

[0163] where h maxThe falling ball height is (600 mm).

[0164] During the ball falling or rebounding process, if the ball touches the inner wall of the tube, the test result of this time is invalid. For each specimen, at least 3 results should be measured within 1 minute, and the median value is taken and denoted as R'. If one of the result values exceeds 20% of the median value, conduct 2 more tests, and determine the median value among the 5 values.

[0165] Take 3 specimens from each polyurethane foam sample and repeat the above process for measurement respectively to obtain R' 1 、R' 2 and R' 3 . Then take the median value of R' 1 、R' 2 and R' 3 as the rebound rate of the sample.

[0166] By comparing the rebound rates of different polyurethane foams, the rebound performance can be compared. The higher the rebound rate, the better the rebound performance.

[0167] The test results are shown in Table 2 below:

[0168] Table 2

[0169]

[0170] As can be seen from the content of Table 2, the average water absorption rate of the polyurethane foams provided in Examples 1 to 25 is 37.7% to 85.5%, the average drying rate is 34.2% to 67.4%, and the rebound rate is 24.7% to 45.3%. The water absorption speed is fast, the drying speed of water is fast, the resilience is good, and the comprehensive performance is excellent.

[0171] Compared with Example 1, if the molar ratio of the hydroxyl group in the polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate in step (1) of the preparation of the modified polyol is on the low side (Example 18), then the proportion of the isocyanate group in the modified polyol is on the high side, and the prepared modified polyol undergoes excessive self-polymerization and has a high viscosity, resulting in difficulty in achieving uniform mixing with other components when preparing the polyurethane foam, and the performance improvement of the prepared polyurethane foam is limited, and the average water absorption rate and average drying rate are relatively low; if the molar ratio of the hydroxyl group in the polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate in step (1) of the preparation of the modified polyol is on the high side (Example 19 or Example 20), then the proportion of the isocyanate group in the modified polyol is on the low side, and the alkoxysilane-functionalized isocyanate and silica with active groups on the surface introduced on the modified polyol are less, resulting in limited performance improvement of the prepared polyurethane foam, and the average water absorption rate and average drying rate are relatively low. It can be seen from this that by controlling the molar ratio of the hydroxyl group in the polyol to the isocyanate group in the alkoxysilane-functionalized isocyanate to be (2 to 3):1, the performance of the prepared modified polyol and polyurethane foam is better.

[0172] Compared with Example 1, if the mass ratio of the polyol described in step (1) and the silica with active groups on the surface described in step (2) in the preparation of the modified polyol is on the low side (Example 22), the viscosity of the prepared modified polyol is high, and it is not easy to achieve uniform mixing with other components during the preparation of polyurethane foam, making the operation difficult. The performance improvement of the prepared polyurethane foam is limited, and the average water absorption rate and average drying rate are relatively low. If the mass ratio of the polyol described in step (1) and the silica with active groups on the surface described in step (2) in the preparation of the modified polyol is on the high side (Example 23), then less silica with active groups on the surface is introduced into the prepared modified polyol, and the performance improvement of the prepared polyurethane foam is limited, and the average water absorption rate and average drying rate are relatively low. It can be seen from this that by controlling the mass ratio of the polyol and the silica with active groups on the surface to be 100:(1-10), the performance of the prepared modified polyol and polyurethane foam is better.

[0173] Compared with Example 1, if the modified polyol is not added (Comparative Example 1), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0174] Compared with Example 1, if the modified polyol is replaced with polyether polyol A and isocyanatopropyltriethoxysilane (Comparative Example 2), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0175] Compared with Example 1, if the modified polyol is replaced with polyether polyol A and fumed silica M-5 (Comparative Example 3), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0176] Compared with Example 1, if the modified polyol is replaced with a mixture of polyether polyol A, isocyanatopropyltriethoxysilane, and fumed silica M-5 (Comparative Example 4), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0177] Compared with Example 1, if the modified polyol is replaced with a polyol-type compound with a silane-modified structure (Comparative Example 5), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0178] Compared with Example 1, if the modified polyol is replaced with a mixture of a polyol-type compound with a silane-modified structure and fumed silica M-5 (Comparative Example 6), the water absorption rate, the drying rate of water, and the resilience of the prepared polyurethane foam are all reduced.

[0179] In summary, the modified polyol of the present invention can improve the drying speed, water absorption speed and resilience of polyurethane foam when applied to the preparation of polyurethane foam.

[0180] The applicant declares that the present invention uses the above embodiments to illustrate a modified polyol and its preparation method and application of the present invention, but the present invention is not limited to the above embodiments, that is, it does not mean that the present invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvement to the present invention, the equivalent substitution of each raw material of the product of the present invention, the addition of auxiliary components, the selection of specific methods, etc. all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A method for preparing a modified polyol, characterized in that: The preparation method comprises the following steps: (1) mixing a polyol and an alkoxysilane-functionalized isocyanate, and reacting the mixture to obtain a polyol-type compound having a silane-modified structure; (2) mixing the polyol compound having a silane-modified structure and the silicon dioxide having active groups on the surface of the polyol compound of step (1) and reacting them to obtain the modified polyol; The active groups in the silicon dioxide having active groups on the surface include hydroxyl groups.

2. The preparation method according to claim 1, characterized in that: The number average molecular weight of the polyol is 800 to 12000 g / mol; The functionality of the polyol is ≥2; The polyol comprises any one or a combination of at least two of vinyl polymer grafted polyether polyol, polyether polyol or polyester polyol; The content of the vinyl polymer in the vinyl polymer grafted polyether polyol is 10wt% to 50wt%; The vinyl polymer in the vinyl polymer grafted polyether polyol comprises an acrylonitrile-styrene copolymer; The polyester polyols include polycarbonate polyols.

3. The preparation method according to claim 1, characterized in that: The alkoxysilane functionalized isocyanate has a structure as shown in Formula 1: In Formula 1, X is selected from any one of a substituted or unsubstituted C1-C18 straight or branched alkylene group, a substituted or unsubstituted C3-C18 cycloalkylene group, a substituted or unsubstituted C2-C18 non-aromatic heterocyclylene group, a substituted or unsubstituted C6-C18 arylene group, and a substituted or unsubstituted C3-C18 heteroarylene group; In Formula 1, R1, R2 and R3 are each independently selected from any one of substituted or unsubstituted C1-C18 alkyl, substituted or unsubstituted C6-C18 aryl, substituted or unsubstituted C3-C18 cycloalkyl, and substituted or unsubstituted C1-C18 alkoxy, and at least one of R1, R2 and R3 is selected from substituted or unsubstituted C1-C18 alkoxy; When the above groups have substituents, the substituents include any one or a combination of at least two of C1-C10 alkyl, C6-C12 aryl or C4-C10 heteroaryl.

4. The preparation method according to claim 3, characterized in that: The X is selected from any one of methylene, ethylene, propylene or butylene; The R1, R2 and R3 are each independently selected from any one of methyl, ethyl, propyl, butyl, methoxy, ethoxy, propoxy or butoxy, and at least one of R1, R2 and R3 is selected from any one of methoxy, ethoxy, propoxy or butoxy.

5. The preparation method according to claim 1, characterized in that: The alkoxysilane functionalized isocyanate includes any one or a combination of at least two of isocyanatepropyltrimethoxysilane, isocyanatepropyltriethoxysilane, isocyanatepropyltripropoxysilane, isocyanatepropyltributoxysilane, isocyanatemethyltrimethoxysilane, isocyanatepropylmethyldiethoxysilane or isocyanatepropylmethyldimethoxysilane; The silicon dioxide having active groups on the surface includes fumed silicon dioxide.

6. The preparation method according to claim 1, characterized in that: Step (1) also includes a step of dehydrating the polyol before the mixing; The molar ratio of the hydroxyl group in the polyol to the isocyanate group in the alkoxysilane functionalized isocyanate in step (1) is (1-10):1; The mass ratio of the polyol in step (1) to the silicon dioxide having active groups on the surface in step (2) is 10:(0.2-20); The mixing in step (1) further comprises adding a catalyst for mixing; The catalyst includes an organotin catalyst; The organotin catalyst includes stannous octoate and / or dibutyltin dilaurate; The mass ratio of the catalyst to the polyol is 100:(0.04-0.08); The reactions in step (1) and step (2) are carried out under an inert atmosphere; The reaction temperature of step (1) is 45-70° C., and the reaction time is 2.0-5.0 h; The reaction temperature in step (2) is 40-65° C., and the reaction time is 0.5-1.5 h.

7. A modified polyol, characterized in that The modified polyol is prepared by the preparation method according to any one of claims 1 to 6.

8. A polyurethane composition, characterized in that The polyurethane composition comprises an A component and a B component, wherein the A component comprises the modified polyol according to claim 7, and the B component comprises a diisocyanate.

9. The polyurethane composition according to claim 8, characterized in that The A component includes the following components by weight: 10-60 parts of the modified polyol as claimed in claim 7, 0-60 parts of polyether polyol, 10-40 parts of vinyl polymer grafted polyether polyol, 2.5-3.5 parts of foaming agent, 0.4-0.8 parts of foam stabilizer and 0.3-0.8 parts of catalyst; The blowing agent includes water; The foam stabilizer includes modified silicone oil; The catalyst in component A includes any one of stannous octoate, bis(dimethylaminoethyl) ether or triethylenediamine, or a combination of at least two thereof; The diisocyanate in the B component includes toluene diisocyanate; The polyurethane composition comprises the following components in parts by weight: 95 to 105 parts of component A and 35 to 40 parts of component B.

10. A polyurethane foam, characterized in that: The polyurethane foam is obtained by foaming the polyurethane composition as claimed in claim 8 or 9.

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