Polyol composition, polyurethane material and application thereof

Abstract

The present invention discloses a polyol composition for preparing a polyurethane material for orthopedic testing. The polyol composition includes a polyether polyol, a foam stabilizer, a catalyst, a crosslinking agent and water. The average hydroxyl value of the polyol composition is 380-490 mgKOH / g, the functionality of the crosslinking agent is ≥2, and the number average molecular weight of the crosslinking agent is ≤400. The present application also discloses a polyurethane material prepared by using the above-mentioned polyol composition as a raw material, and the application of the polyurethane material in orthopedic testing. The present application can provide a polyol composition for preparing polyurethane for orthopedic testing, and the polyurethane material prepared by the composition has good screw pull-out strength and meets the requirements of ASTM F1839. The polyol composition disclosed in the present application can make the preparation process of the polyurethane material have high flexibility, and can conveniently adjust the range of screw pull-out strength according to the requirements of different density grades.

Description

Technical Field

[0001] The invention belongs to the technical field of polymer materials, and in particular relates to a polyol composition, a polyurethane material prepared by using the polyol, and applications of the polyurethane material. Background Art

[0002] At present, some rigid polyurethane foams with specific densities can show a closed-cell structure similar to human cancellous bone, and their uniformity and consistency make them ideal materials for orthopedic testing. In order to ensure that the mechanical properties are similar to those of human cancellous bone, the ASTM F1839 standard has clear requirements for various properties of polyurethane materials, among which screw pull-out strength is one of the key indicators.

[0003] According to the ASTM F1839 standard, polyurethane materials need to meet specific screw pull-out force requirements within a specific density range. For example, the core density of grade 15 polyurethane materials must meet 216-264.5 kg / cm 3 , and its screw pull-out force must meet 464.5~831.0N. In order to take into account both the cost and performance of the material, it is usually hoped that qualified products can be obtained at a lower density level. However, at present, there are few studies on the performance of pure polyurethane materials involving screw pull-out strength, and under existing technical conditions, changes in density will also have a greater impact on the screw pull-out force, and ultimately it is difficult to take into account the screw pull-out force at a low density level.

[0004] Therefore, how to achieve convenient and effective adjustment of the screw pull-out force within a specific density range is still a technical problem that urgently needs to be solved in this field. Summary of the invention

[0005] In order to solve the above problems, the primary objective of the present application is to provide a polyol composition for preparing a polyurethane material for orthopedic testing, wherein the polyol composition comprises a polyether polyol, a foam stabilizer, a catalyst, a cross-linking agent and water, wherein the average hydroxyl value of the polyol composition is 380 to 490 mgKOH / g, the functionality of the cross-linking agent is ≥2, and the number average molecular weight of the cross-linking agent is ≤400.

[0006] The study found that there are many factors affecting the screw pull-out strength, including the density and toughness of the material, the shape of the pores inside the material, the distribution of the pores, etc. The inventors of the present application unexpectedly discovered in the study that under the synergistic effect of a higher hydroxyl value (the average hydroxyl value is 380-490 mgKOH / g) and a specific cross-linking agent (functionality ≥ 2 and molecular weight ≤ 400), the polyol composition reacts with isocyanate to form a cross-linking density and pore shape that are beneficial to the screw pull-out strength, which can ensure the integrity of the polyurethane material when the screw is screwed in, and facilitate the adjustment of the screw pull-out strength within a specific density range to meet the screw pull-out force requirements of polyurethane materials of relevant density grades.

[0007] The crosslinking agent described in the present invention refers to a low molecular weight compound that can cause polyurethane to produce a crosslinked network structure. The low molecular weight refers to a molecular weight ≤400. The crosslinking agent preferably has a functionality ≥2 and is a low molecular weight compound containing active hydrogen that can react with isocyanate. In the present invention, alcohol and alcohol amine crosslinking agents are preferred.

[0008] The alcohol crosslinking agent can be selected from low molecular weight polyols containing ether bonds, C1-C6 alkyl alcohols or low molecular weight polycaprolactone polyols. The low molecular weight polyols containing ether bonds described in the present invention refer to low molecular weight polyols obtained by reacting active hydrogen-containing compounds with olefin oxides, and can be low molecular weight polyether polyols or low molecular weight non-polyether polyols. Preferably, the low molecular weight non-polyether polyol is prepared according to the following material ratio: the molar ratio of olefin oxide to active hydrogen-containing compounds is ≤ the functionality of active hydrogen-containing compounds. Taking the low molecular weight non-polyether polyol obtained by the reaction of pentaerythritol and propylene oxide as an example, the functionality of pentaerythritol is 4, therefore, the molar ratio of propylene oxide to pentaerythritol is ≤4, that is, the low molecular weight non-polyether polyol thus obtained is the reaction product of 1 mole of pentaerythritol and ≤4 moles of propylene oxide.

[0009] The C1-C6 alkyl alcohol can be selected from at least one of ethylene glycol, propylene glycol, butylene glycol, hexylene glycol, glycerol, trimethylolpropane, pentaerythritol, etc. The alcohol amine can be selected from at least one of triethanolamine, diethanolamine, or monoethanolamine, etc.

[0010] Furthermore, in order to take into account a good compression modulus, the functionality of the crosslinking agent is preferably 2 to 4, and the equivalent weight is 20 to 133. The equivalent weight in the present invention refers to the molecular weight corresponding to the unit functionality in each compound molecule.

[0011] Furthermore, based on the total mass of the polyol composition, the mass proportion of the cross-linking agent is 0.2-18.3 wt %.

[0012] Due to the particularity of polyurethane materials for orthopedic testing, the requirements for screw pull-out strength are not as high as possible, but need to meet the specific screw pull-out capacity within a certain density level range. Therefore, the mass proportion of the cross-linking agent is optimized. Based on the total mass of the polyol composition, when the mass proportion of the cross-linking agent is 0.2-18.3wt%, the relevant requirements of polyurethane materials for orthopedic testing can be met. In addition, for polyurethane materials for orthopedic testing with different density levels, the requirements for screw pull-out strength are also different. For core density of 72-176kg / m 3 The polyurethane material for orthopedic testing has a screw pull-out strength requirement of 56N≤screw pull-out force≤453N; the core density is 176~350kg / m 3 The polyurethane material for orthopedic testing has a screw pull-out strength requirement of 309N≤screw pull-out force≤1310N; the core density is 350~440kg / m 3 The polyurethane material for orthopedic testing has a screw pull-out strength requirement of 1125N≤screw pull-out force≤1890N.

[0013] At present, in order to meet different screw pull-out strength requirements for orthopedic testing polyurethane materials of different density levels, a large number of tests need to be conducted to obtain the corresponding raw material formula. By using the present application, it is possible to obtain polyurethane materials with different screw pull-out strengths while keeping other components of the formula unchanged and only adjusting the type and / or amount of the cross-linking agent therein while ensuring that the material density is still within the required level range.

[0014] The core density of the polyurethane material for orthopedic testing is preferably less than 179 kg / m 3 When the total mass of the polyol composition is used as a reference, the mass proportion of the crosslinking agent is 0.2 to 8.9 wt %; the core density of the polyurethane material for orthopedic testing is 179 to 350 kg / m 3 When the total mass of the polyol composition is used as a reference, the mass proportion of the crosslinking agent is 1 to 12 wt%; the core density of the polyurethane material for orthopedic testing is greater than 350 kg / m 3 When the total mass of the polyol composition is used as a reference, the mass ratio of the cross-linking agent is 5 to 18.3 wt %. Within the above core density ranges, different screw pull-out strengths of the polyurethane material can be adjusted by simply adjusting the mass ratio of the cross-linking agent in the formula, while the core density of the polyurethane material remains within the above ranges.

[0015] The polyether polyol of the present invention can be any known in the art, and is usually prepared by ring-opening polymerization with an epoxy compound under the action of a catalyst using a low molecular weight polyol, a polyamine or an active hydrogen compound as an initiator, and the epoxy compound can be selected from ethylene oxide, propylene oxide, butylene oxide, cyclopentane oxide, cyclohexene oxide, etc. The initiator can be selected from sucrose, glycerol, trimethylolpropane, sorbitol, mannitol, xylitol, aromatic amines, aliphatic amines, alkyl alcohols, alcohol amines, etc. Further, the polyether polyol includes polyether polyol A and polyether polyol B, the functionality of the polyether polyol A is 5 to 8, the molecular weight is 700 to 1300, and the functionality of the polyether polyol B is 2 to 4, and the molecular weight is 400 to 800. The combined use of polyether polyol A and polyether polyol B can take into account the fluidity of the polyurethane reaction stock solution and the crosslinking density of the polyurethane foam material, prevent the foam from becoming brittle or the surface from being too soft, and avoid deformation or damage of the polyurethane foam during the cutting process. It is further preferred that the average functionality of the polyether polyol formed by the polyether polyol A and the polyether polyol B is 3 to 5, and the mass proportion of polyether polyol A is 5-40% based on the total mass of polyether polyol A and polyether polyol B, so as to take into account the uniformity of density distribution and compression modulus. When there is too much polyether polyol A, the viscosity of the system increases too fast, the fluidity is poor, and the density distribution of the polyurethane material is uneven. When there is too little polyether polyol A, the degree of crosslinking is insufficient, and indicators such as the compressive strength of the polyurethane material deteriorate.

[0016] Furthermore, based on the total mass of the polyol composition, the mass proportion of water is 0.1-1.0wt%, so as to prevent cracking on the surface or inside of the polyurethane and take into account the fluidity of the polyurethane reaction materials. The water in the present invention is the total content of water in the polyol composition, including added water and water in the raw materials.

[0017] The present invention can use any conventional catalyst in the art, including amine catalysts and / or organic metal salt catalysts, which can be divided into foaming catalysts, gel catalysts and trimerization catalysts according to the different functions of the catalysts. The foaming catalyst can be selected from bis(dimethylaminoethyl) ether, pentamethyldiethylenetriamine, tetramethylhexanediamine, triethylamine, tributylamine, etc.; the gel catalyst can be selected from triethylenediamine, N-methyldicyclohexylamine, N-methylmorpholine, N-ethylmorpholine, N,N'-dimethylbenzylamine, 1,2-dimethylimidazole, N-methylimidazole, dibutyltin dilaurate, stannous octoate, N,N-dimethylcyclohexylamine, etc.; the trimerization catalyst can be selected from 1,3,5-tris(dimethylaminopropyl)-hexahydrotriazine, 2,4,6-tris(dimethylaminomethyl)phenol, potassium isooctanoate, potassium acetate, etc. The composite use of the above catalysts with different functions is beneficial to the density distribution of the polyurethane material, so that it meets the density distribution requirements of the polyurethane material for orthopedic testing. Preferably, when the catalyst is used in combination, the amount of the foaming catalyst is 0-0.8wt% based on the total mass of the polyol composition, so as to control the milky time of the polyurethane reaction to 25-50s, reduce the generation of invalid foam layer, and take into account production efficiency. The above-mentioned foaming catalyst refers to a type of catalyst that has catalytic performance on the foaming reaction of polyurethane, the gelling catalyst refers to a type of catalyst that has catalytic performance on the gelling reaction of polyurethane, and the trimerization catalyst refers to a type of foaming agent that has catalytic performance on the trimerization reaction of isocyanate.

[0018] The foam stabilizer that can be used in the present invention is a polyether-modified silicone surfactant containing a polysiloxane-olefin oxide block or graft copolymer, which has a relatively low surface performance, can promote the dispersion of substances and improve the compatibility between materials, and is also conducive to the formation of uniform and fine bubbles. It can be selected from AK8805, AK8830, AK8818, AK8815, AK8485, AK8812, AK8809, etc. of Meside, B8460, B8462, B8461, B8544, B8494, B8532, B8471, B8474, B8476, B8481, B8465 of Evonik, and L6900, L6863, L6912, L6988, etc. of Maitu.

[0019] The polyol composition of the present invention also includes polyester polyols, which are compounds containing ester groups or carbonate groups, and can be selected from conventional polyester polyols, polycaprolactone polyols, polycarbonate polyols, etc., wherein conventional polyester polyols are usually prepared by reacting polycarboxylic acids (or anhydrides or esters) with polyols (or polyol amines). Further, in order to take into account better shear strength and shear modulus, the polyester polyol of the present invention preferably contains a benzene ring polyester polyol, such as phthalic anhydride polyester polyol, etc.

[0020] The physical foaming agent in the present invention can be selected from physical foaming agents known in the art, specifically selected from alkane compounds, fluoroolefin compounds, hydrofluorocarbon compounds, carbon dioxide, alcohols containing 1 to 5 carbon atoms, aldehydes containing 1 to 4 carbon atoms, ethers or diethers containing 1 to 4 carbon atoms, organic acids or organic acid esters, wherein the alkane compound is preferably an alkane with a boiling point of -45°C to 100°C, such as cyclopentane, isopentane, n-pentane, neopentane and other pentanes, n-butane, isobutane and other butanes, n-hexane and its isomers, n-heptane and its isomers, etc., and the fluoroolefin compound refers to an alkane not substituted by a halogen atom. Fluoroolefin compounds or fluorine olefin compounds substituted by halogen atoms, fluorine olefin compounds not substituted by halogen atoms are preferably monofluoropropylene, difluoropropylene, trifluoropropylene, tetrafluoropropylene, pentafluoropropylene, hexafluoropropylene, monofluorobutene, difluorobutene, trifluorobutene, tetrafluorobutene, pentafluorobutene, hexafluorobutene, heptafluorobutene, octafluorobutene, octafluoropentene or difluoroethylene, etc., fluorine olefin compounds substituted by halogen atoms refer to hydrogen on carbon atoms replaced by one or more halogens, such as chlorine-substituted trifluoropropylene, chlorine-substituted tetrafluoropropylene, etc.; hydrofluorocarbon compounds can be selected from pentafluoropropane, pentafluorobutane, difluoroethane or tetrafluoroethane, etc. Preferably, in order to reduce the number of pores on the cut surface, the present invention preferably contains at least one of trans-1-chloro-3,3,3-trifluoropropene, pentane and methyl formate as the physical foaming agent.

[0021] Secondly, the present invention also provides a polyurethane material, the raw materials of which include polyisocyanate and any of the above-mentioned polyol compositions, and the isocyanate index is 0.85 to 1.15. The isocyanate index refers to the molar ratio of the reactive groups of the polyisocyanate to the reactive groups in the polyol composition, that is, the molar ratio of the reactive groups NCO of the polyisocyanate to the reactive groups OH of the polyol composition. The polyurethane material can meet the requirements of relevant standards and be used for orthopedic tests. During production, the conventional production process of existing polyurethane materials can be adopted.

[0022] Further, the polyurethane foam for bone model is preferably prepared from raw materials including the following components in percentage by weight: 45-52 wt% of a polyol composition, 1.4-4.2 wt% of a physical foaming agent, and 46-53 wt% of a polyisocyanate, and the total amount of the above components is 100%. The polyol composition does not include a physical foaming agent, that is, during the production process, even if part or all of the physical foaming agent is pre-mixed in the polyol composition and / or the polyisocyanate, the physical foaming agent contained is not included when calculating the polyol composition and the polyisocyanate. The physical foaming agent includes the total amount of the physical foaming agent pre-added in the polyol composition and / or the polyisocyanate and the physical foaming agent added separately.

[0023] The material foaming agent preferably includes at least one of trans-1-chloro-3,3,3-trifluoropropylene pentane and methyl formate.

[0024] The polyisocyanate of the present invention can be any known polyisocyanate in the art, and can be polymethylene polyphenyl polyisocyanate (abbreviated as polymeric MDI), modified polyisocyanate, etc. When two or more polyisocyanates are selected, they can be mixed in any proportion. Polymeric MDI with an average functionality of 2.7 to 2.9 is preferred to take into account the crosslinking density and improve the dimensional stability. Polymeric MDI with an average functionality of 2.7 can be selected from PM200, 44v20L, M20s, Any one of PM2010, the polymeric MDI with an average functionality of 2.9 can be selected from M50, PM400, 44V40L, 2085. Modified polyisocyanate refers to a substance with a surplus of NCO groups obtained by reacting polyols with polyisocyanates. The polyols used can be polyether polyols with glycerol, ethylene glycol, diethylene glycol, pentaerythritol, etc. as initiators, or phthalic anhydride polyester polyols, and bio-based polyols can also be used. Bio-based polyols are polyol compounds prepared with soybean oil, castor oil, rapeseed oil, tung oil, olive oil, palm oil or derivatives of the above substances as raw materials, such as castor oil polyols, olive oil polyols, palm oil polyols, castor oil derivative polyols, etc.

[0025] Finally, the present application provides the application of any of the above-mentioned polyurethane materials in orthopedic testing. The polyurethane material prepared by the present invention meets the performance index requirements of ASTM F1839, can be used in the field of orthopedic testing, and can conveniently and accurately evaluate the performance of orthopedic instruments. The orthopedic instruments described in the present invention refer to professional medical instruments specifically used for orthopedic surgery, including but not limited to orthopedic knives, scissors, pliers, hooks, needles, scrapers, cones, drills, saws, chisels, files, shovels, screws, etc.

[0026] In general, the beneficial effects of the present invention are:

[0027] (1) A polyol composition capable of preparing polyurethane for orthopedic testing is provided, and the polyurethane material prepared from the composition has good screw pull-out strength and meets the requirements of ASTM F1839;

[0028] (2) The polyol composition of the present invention can make the preparation process of the polyurethane material more flexible, and can conveniently adjust the range of the screw pull-out strength according to the requirements of different density grades. DETAILED DESCRIPTION

[0029] In order to better understand the present invention, the content of the present invention is further explained below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0030] Some of the raw materials used in the present invention are as follows:

[0031] (1) Polyether polyol A

[0032] Polyether polyol A1: self-made, the initiator is sucrose, the molecular weight is 701, and the functionality is 8;

[0033] Polyether polyol A2: self-made, the initiator is xylitol, the molecular weight is 1302, and the functionality is 5;

[0034] Polyether polyol A3: self-made, the initiators are sucrose and ethylene glycol, the molecular weight is 1013, and the functionality is 6;

[0035] Polyether polyol A4: self-made, the initiator is sorbitol, the molecular weight is 805, and the functionality is 6;

[0036] Polyether polyol A5: Homemade, the initiators are sucrose and glycerol, the molecular weight is 751, and the functionality is 7.

[0037] (2) Polyether polyol B

[0038] Polyether polyol B1: self-made, the initiator is pentaerythritol, the molecular weight is 459, and the functionality is 4;

[0039] Polyether polyol B2: self-made, the initiator is propylene glycol, the molecular weight is 800, and the functionality is 2;

[0040] Polyether polyol B3: self-made, the initiator is 1,4-butanediol, the molecular weight is 553, and the functionality is 2;

[0041] Polyether polyol B4: homemade, initiators are sucrose and diethylene glycol, molecular weight is 707, functionality is 3;

[0042] Polyether polyol B5: homemade, initiator is glycerol, molecular weight is 400, functionality is 3;

[0043] Polyether polyol B6: Homemade, the initiator is toluene diamine, the molecular weight is 652, and the functionality is 4.

[0044] (3) Polyether polyol C

[0045] Polyether polyol C1: homemade, with sucrose and glycerol as initiators, molecular weight of 1458, functionality of 7;

[0046] Polyether polyol C2: self-made, the initiator is glycerol, the molecular weight is 967, and the functionality is 3;

[0047] Polyether polyol C3: Homemade, the initiator is toluene diamine, the molecular weight is 900, and the functionality is 4.

[0048] (4) Phthalic anhydride polyester polyol

[0049] Homemade, the initiator is diethylene glycol, the molecular weight is 280, and the functionality is 3.

[0050] (5) Cross-linking agent

[0051] Crosslinker C1: trimethylolpropane, molecular weight 134, functionality 3;

[0052] Crosslinking agent C2: diethylene glycol, molecular weight 106, functionality 2;

[0053] Crosslinker C3: a self-made low molecular weight polyol containing ether bonds, prepared from triethanolamine and ethylene oxide in a molar ratio of 1:3, with a molecular weight of 270 and a functionality of 2.97;

[0054] Crosslinker C4: a self-made low molecular weight polyol containing ether bonds, prepared from pentaerythritol and propylene oxide in a molar ratio of 1:4, with a molecular weight of 365 and a functionality of 3.92;

[0055] Crosslinker C5: a self-made low molecular weight polyol containing ether bonds, prepared from ethylenediamine and propylene oxide in a molar ratio of 1:4, with a molecular weight of 290 and a functionality of 4;

[0056] Crosslinker C6: a homemade low molecular weight polyether polyol prepared from glycerol and propylene oxide in a molar ratio of 1:5.2, with a molecular weight of 400 and a functionality of 2.8;

[0057] Crosslinker C7: Polycaprolactone polyol 3031, the initiator is trimethylolpropane, the molecular weight is 300, and the functionality is 2.99;

[0058] Crosslinker C8: ethanolamine, molecular weight 61, functionality 3;

[0059] Crosslinker C9: diethanolamine, molecular weight 105, functionality 3;

[0060] Crosslinking agent C10: a self-made low molecular weight polyether polyol prepared from glycerol and propylene oxide in a molar ratio of 1:13, with a molecular weight of 800 and a functionality of 2.8.

[0061] The mass proportion of water in the present invention is determined by the method in GB / T 22313.

[0062] The grades of the products of the present invention are classified according to the provisions of ASTM F1839.

[0063] The core density, dimensional stability, compression strength, compression modulus, shear strength, shear modulus, screw pull-out strength and other properties of the present invention are tested according to the provisions of ASTM F1839.

[0064] The surface condition of the present invention refers to whether there are holes or cracks larger than 6 mm on the surface of the sample obtained after the polyurethane material is cut off from the epidermis. If there are holes or cracks, the surface condition is poor, and if not, the surface condition is good.

[0065] Examples 1 to 13 of the present invention and Comparative Examples 1 to 6 use the raw materials in Table 1 and Table 2 to prepare polyol compositions.

[0066] Table 1 Polyol composition formula of Examples 1 to 6 and Comparative Examples 1 to 4

[0067]

[0068] Table 2 Polyol composition formula of Examples 7 to 13 and Comparative Examples 5 to 6

[0069]

[0070] The preparation method of the polyurethane material of the present invention can be carried out in a conventional manner in the art, or in a process-optimized scheme. For the sake of illustration, the present invention will adopt a conventional manner in the art to prepare the polyurethane material, that is, after the polyol composition is evenly mixed, it is mixed with a physical foaming agent and a polyisocyanate at a high speed and injected into a mold, and the polyurethane material is obtained after curing and molding.

[0071] It can be understood that in another embodiment, the physical blowing agent can be divided into two parts, one part of which is premixed with the polyol composition to form a polyol premix, and the other part is used as a physical blowing agent as a separate component. The polyol premix, the separate component physical blowing agent and the polyisocyanate are then mixed with high-speed stirring and injected into a mold.

[0072] Examples 1 to 13 of the present invention and comparative examples 1 to 6 use the raw materials in Table 3 and Table 4 to prepare polyurethane materials.

[0073] Table 3 Raw material composition of polyurethane materials of Examples 1 to 6 and Comparative Examples 1 to 4

[0074]

[0075] Table 4 Raw material composition of polyurethane materials of Examples 7 to 13 and Comparative Examples 5 to 6

[0076]

[0077]

[0078] The performance of the prepared polyurethane material was characterized, and the results are shown in Tables 5 and 6.

[0079] Table 5 Performance of polyurethane materials of Examples 1 to 6 and Comparative Examples 1 to 4

[0080]

[0081] Note: *Indicates that the polyurethane material broke when the screw entered the polyurethane material.

[0082] As can be seen from Table 5, the present invention can adjust the screw pull-out force only by using a cross-linking agent, and obtain a polyurethane material for orthopedic testing with performance that meets the requirements, thereby achieving convenient and effective adjustment of the screw pull-out force within a specific density range. Although the core density of the comparative example reaches the requirement of grade 12, the polyol composition used therein does not meet the defined characteristics of the present invention regarding the average hydroxyl value, cross-linking agent functionality, cross-linking agent molecular weight, etc., so that the obtained polyurethane material does not obtain a qualified screw pull-out force under both lower and higher density conditions, and cannot achieve convenient and effective adjustment of the screw pull-out force.

[0083] Table 6 Performance of polyurethane materials of Examples 7 to 13 and Comparative Examples 5 to 6

[0084]

[0085]

[0086] Table 6 lists some preferred solutions of the embodiments of the present invention. It can be seen from the comparison with Comparative Example 5 that although Comparative Example 5 does not use the material composition of the preferred solution, it can also prepare a polyurethane material that meets ASTM F1839. However, compared with Example 12, at the same density level, the comprehensive performance of Comparative Example 5 is significantly worse, which is not conducive to reducing the material density, especially in terms of dimensional stability. Due to the poor uniformity of density distribution, the dimensional deformation is large. At the same time, although the polyurethane material obtained in Comparative Example 5 does not have holes or cracks larger than 6mm on the surface, its surface texture is relatively soft and is not convenient for further cutting and processing. The isocyanate index used in Comparative Example 6 exceeds the range, which brings performance defects of the polyurethane material and cannot meet the requirements of ASTM F1839.

[0087] In summary, the polyol composition of the present invention not only has good flexibility and convenient operability, but also the polyurethane material prepared by the present invention has good compressive strength, shear strength and other properties, can meet the performance requirements of ASTM F1839, and can be used in the field of orthopedic testing.

Claims

1. A polyol composition, characterized in that It comprises a polyether polyol, a foam stabilizer, a catalyst, a crosslinking agent and water, wherein the average hydroxyl value of the polyol composition is 380-490 mgKOH / g, the functionality of the crosslinking agent is ≥2, and the number average molecular weight of the crosslinking agent is ≤400; The polyether polyol comprises polyether polyol A and polyether polyol B. The functionality of polyether polyol A is 5-8, and the number average molecular weight of polyether polyol A is 700-1300; the functionality of polyether polyol B is 2-4, and the number average molecular weight of polyether polyol B is 400-800.

2. The polyol composition according to claim 1, characterized in that Based on the total mass of the polyol composition, the mass of the cross-linking agent accounts for 0.2 to 18.3 wt %.

3. The polyol composition according to claim 1, characterized in that Based on the total mass of the polyol composition, the mass proportion of water is 0.1-1.0 wt %.

4. The polyol composition according to claim 1, characterized in that The polyol composition also includes phthalic anhydride polyester polyol.

5. The polyol composition according to any one of claims 1 to 4, characterized in that The invention also comprises a physical foaming agent, which comprises at least one of trans-1-chloro-3,3,3-trifluoropropene, pentane and methyl formate.

6. Polyurethane material, characterized in that: The raw materials include polyisocyanate and the polyol composition according to any one of claims 1 to 4, and the isocyanate index is 0.85 to 1.

15.

7. The polyurethane material according to claim 6, characterized in that: The raw materials include the following components in percentage by weight: The polyol composition comprises 45-52 wt %, the physical foaming agent comprises 1.4-4.2 wt % and the polyisocyanate comprises 46-53 wt %. The total amount of the above components is 100 %.

8. The polyurethane material according to claim 7, characterized in that: The physical foaming agent contains at least one of trans-1-chloro-3,3,3-trifluoropropene, pentane and methyl formate.

9. Use of the polyurethane material according to any one of claims 7 to 8 in orthopedic testing.

Images