Rigid polyurethane materials and their preparation methods and applications

Abstract

The present invention relates to a rigid polyurethane material, its preparation method and application, and mainly solves the problem that the rigid foam with good sound absorption in the prior art has poor flame retardancy. The present invention adopts a rigid polyurethane material, which is composed of component A and component B. The weight ratio of component A to component B is 100:100-110. Component A includes, by weight: 5-15 parts of polyester polyol, 5-10 parts of rigid foam polyol, 68-76 parts of flame retardant, 0.5-1.0 part of foam stabilizer, 2-4 parts of catalyst, 5-8 parts of foaming agent, 0.2-0.4 part of cell opener, and 0.5-1.5 parts of antioxidant; the polyester polyol is a flame-retardant polyester polyol with an average molecular weight of 400-500, a functionality of 1-3, and a hydroxyl value of 200-260 mgKOH / g; the rigid foam polyol is a flame-retardant polyol with an average molecular weight of 400-650, a functionality of 2-3, and a hydroxyl value of 200-300 mgKOH / g; the flame retardant is at least two of phosphate ester flame retardants; the catalyst is selected from at least one of amine catalysts or metal catalysts. The above problems are preferably solved by the technical solution, and it can be used in the field of polyurethane spraying.

Description

Technical Field

[0001] The present invention relates to the field of rigid polyurethane foams, and particularly to a rigid polyurethane material, a preparation method thereof, and an application thereof. Background Art

[0002] At present, there are generally two types of commonly used sound-absorbing materials on the market. One is a high-flame-retardant rock wool composite board, and the other is a polyurethane composite board. The high-flame-retardant rock wool composite board has high costs and great construction difficulties, while the foam density of a conventional polyurethane composite board is generally about 35 kg / m 3 or so. The thermal conductivity of this density foam is relatively low, but it has high costs and large weights, and is not a good choice for the automotive ceiling with high lightweight requirements. Although there have been all-water low-density sound-absorbing foams on the market in recent years, their oxygen indices are generally about 23%, which cannot meet the fire prevention requirements of national policies and the general public for thermal insulation materials. Therefore, the flame retardancy problem of polyurethane materials has become an urgent problem to be solved. In addition, the sound-absorbing materials with low-density all-water spraying in the prior art generally have low strengths, and have problems such as severe shrinkage, heartburn, and poor adhesion to the substrate.

[0003] Chinese Patent CN103910854B discloses a low-density flame-retardant semi-rigid polyurethane foam, which is prepared by a foaming process from an A component comprising a mixture of a combined polyether polyol, water, a surfactant, a catalyst, and a flame retardant, and an MDI-based isocyanate as a B component; the weight ratio of the combined polyether polyol of the A component to the MDI-based isocyanate of the B component is 70:110 - 230; the weight ratio of the A component and the B component is 100:100 - 200; the combined polyether polyol comprises 40 - 70 wt% of polyether 1, 15 - 40 wt% of polyether 2, and 3 - 20 wt% of polyether 3. To a certain extent, the rigidity and flame retardant performance are improved, but it uses expanded graphite as an inorganic flame retardant, which damages the spray gun, and does not mention the specific oxygen index. If it cannot reach more than 28%, it cannot meet the spraying requirements of a bus.

[0004] Chinese Patent CN112279991A discloses an all-water ultra-low density open-cell rigid polyurethane foam and a preparation method thereof. The provided all-water ultra-low density open-cell rigid polyurethane foam uses two different types of polyether polyols as reaction raw materials, and uses a specific open-cell silicone oil as an open-cell agent, and is mixed and reacted with a water blowing agent and an isocyanate, which improves the open-cell rate of the polyurethane foam and at the same time enables the foam to have good strength, but does not mention the flame retardant performance such as the oxygen index and the sound-absorbing performance, and cannot meet the spraying requirements of a bus.

[0005] The sound absorption performance is to test the sound absorption coefficient of the material according to the national standard "GB / T 18696.1-2004 Acoustics - Measurement of sound absorption coefficient and acoustic impedance in impedance tubes - Part 1: Standing wave ratio method"; the test range of this equipment is 100 - 6300 Hz. The test specimens are respectively cut into circular specimens with a diameter of 9.6 cm and a diameter of 3 cm. The 9.6 cm specimens are used to test the low-frequency sound absorption coefficient, and the 3 cm specimens are used to test the high-frequency sound absorption coefficient. Its average sound absorption coefficient is the average coefficient calculated at 125 Hz, 250 Hz, 500 Hz, 1000 Hz, 2000 Hz, and 4000 Hz.

[0006] Generally, materials with a sound absorption coefficient greater than 0.2 are considered sound-absorbing materials, and those with a sound absorption coefficient greater than 0.5 are good sound-absorbing materials. Summary of the Invention

[0007] One of the technical problems to be solved by the present invention is the problem that the hard polyurethane material with good sound absorption performance in the prior art has poor flame retardancy. A new hard polyurethane material is provided, which has the advantage of high flame retardancy under the condition of good sound absorption performance.

[0008] The second technical problem to be solved by the present invention is to provide a preparation method of the hard polyurethane material corresponding to solving the first technical problem.

[0009] The third technical problem to be solved by the present invention is to provide an application of the hard polyurethane material corresponding to solving the first technical problem.

[0010] To solve the first of the above technical problems, the technical solution adopted by the present invention is as follows: A hard polyurethane material is composed of component A and component B. The weight ratio of component A to component B is 100:100 - 110. Component A, by weight, includes: 5 - 15 parts of polyester polyol, 5 - 10 parts of rigid foam polyol, 68 - 76 parts of flame retardant, 0.5 - 1.0 part of foam stabilizer, 2 - 4 parts of catalyst, 5 - 8 parts of water, 0.2 - 0.4 part of cell opener, and 0.5 - 1.5 parts of antioxidant; wherein, the polyester polyol is a flame-retardant polyester polyol with an average molecular weight of 400 - 500, a functionality of 1 - 3, and a hydroxyl value of 200 - 260 mgKOH / g; the rigid foam polyol is a flame-retardant polyol with an average molecular weight of 400 - 650, a functionality of 2 - 3, and a hydroxyl value of 200 - 300 mgKOH / g; the flame retardant is selected from at least two of phosphate ester flame retardants; the foam stabilizer is selected from at least one of non-hydrolyzable silicon-carbon surfactants or polysiloxane surfactants; the catalyst is selected from at least one of amine catalysts or metal catalysts; component B is polymethylene polyphenyl polyisocyanate.

[0011] In the above technical solution, preferably, the polyester polyol is selected from at least one of HF-8730, Terol 250 or PS-7001.

[0012] In the above technical solution, preferably, the rigid foam polyol is selected from at least one of CNP-8119, Saytex RB-79 or XOLM125.

[0013] In the above technical solution, preferably, the rigid foam polyol CNP-8119 is prepared by the following steps:

[0014] (1) Melamine, paraformaldehyde, methanol and diethanolamine are added to a reaction vessel in a molar ratio of 1:6:9:3, and stirred evenly to obtain Material I;

[0015] (2) Material I is reacted under normal pressure, the reaction temperature is 55 °C, and the reaction time is 3 h to obtain Material II;

[0016] (3) Diethyl phosphite is added dropwise to Material II, the dropping time is 1 h, and the molar ratio of the added diethyl phosphite to the melamine in step (1) is 3:1 to obtain Material III;

[0017] (4) Material III is heated to 75 °C, and a phosphoric acid aqueous solution with a mass percentage concentration of 30% is added to adjust the pH value to 4.0, and the reaction continues for 3 h to obtain Material IV;

[0018] (5) After the reaction is completed, a sodium hydroxide aqueous solution with a mass percentage concentration of 30% is added to Material IV to adjust the pH value to 7.5, and small molecule by-products are removed by vacuum distillation. The vacuum distillation temperature is 75 °C, and the pressure is -0.098 MPa (gauge pressure). After filtering to remove solid salts, the rigid foam polyol CNP-8119 with a hydroxyl value of 280 mg KOH / g, a viscosity of 1640 mPa·s / 25 °C and a functionality of 3 is obtained.

[0019] In the above technical solution, preferably, the flame retardant is selected from at least two of tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(dichloropropyl) phosphate or triethyl phosphate; the catalyst is selected from at least three of Polycat 5, Polycat 41, Niax A-33, Dabco T-12, Dabco K-15 or Niax A-1.

[0020] In the above technical solution, preferably, the cell opener is selected from at least one of Ortegol 501 or AK-9901; the antioxidant is selected from at least one of 1035 or 1010; the foam stabilizer is selected from at least one of B-1048, L-6900 or AK-8805.

[0021] To solve the second of the above technical problems, the technical solution adopted by the present invention is as follows: A preparation method of a rigid polyurethane material, comprising the following steps:

[0022] (1) Prepare raw materials according to the following component weight parts:

[0023] Component A includes, by weight parts: 5 - 15 parts of polyester polyol, 5 - 10 parts of rigid foam polyol, 68 - 76 parts of flame retardant, 0.5 - 1.0 part of foam stabilizer, 2 - 4 parts of catalyst, 5 - 8 parts of water, 0.2 - 0.4 part of open-cell agent, 0.5 - 1.5 parts of antioxidant; wherein, the polyester polyol is a flame-retardant polyester polyol, with an average molecular weight of 400 - 500, functionality of 1 - 3, and hydroxyl value of 200 - 260mgKOH / g; the rigid foam polyol is a flame-retardant polyol, with an average molecular weight of 400 - 650, functionality of 2 - 3, and hydroxyl value of 200 - 300mgKOH / g; the flame retardant is selected from at least two of phosphate ester flame retardants; the foam stabilizer is selected from at least one of non-hydrolyzable silicon-carbon surfactants or polysiloxane surfactants; the catalyst is selected from at least one of amine catalysts or metal catalysts; Component B is polymethylene polyphenyl polyisocyanate; the weight part ratio of Component A to Component B is 100:100 - 110;

[0024] (2) Prepare Component A

[0025] According to the components and weight parts in step (1), add all the raw materials in Component A to container A in sequence, stir at normal temperature for 1 - 1.5 hours, and mix thoroughly to obtain Component A;

[0026] (3) Prepare Component B

[0027] According to the component weight parts in step (1), add polymethylene polyphenyl polyisocyanate to container B, and stir for 5 - 15 minutes to obtain Component B;

[0028] (4) Atomize and foam Component A and Component B through a high-pressure spraying foaming machine, and after the foam is formed, cure it to obtain a rigid polyurethane material.

[0029] In the above technical solution, preferably, the operating conditions of the high-pressure spraying foaming machine are: the pressure of the equipment is 1600 - 2100psi, the temperature is 25 - 30°C; the spray gun speed swings evenly during spraying; the construction environment temperature is not lower than 15°C, the relative humidity is less than 85%, the wind force is not greater than level 3, and the spraying thickness per layer is controlled within 20mm.

[0030] In the above technical solution, preferably, the polyester polyol is selected from at least one of HF-8730, Terol 250 or PS-7001; the rigid foam polyol is selected from at least one of CNP-8119, Saytex RB-79 or XOL M125; the flame retardant is selected from at least two of tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(dichloropropyl) phosphate or triethyl phosphate; the catalyst is selected from at least three of Polycat 5, Polycat 41, Niax A-33, Dabco T-12, Dabco K-15 or Niax A-1.

[0031] To solve the third of the above technical problems, the technical solution adopted by the present invention is to use the prepared rigid polyurethane material in the field of polyurethane foam spraying for large buses.

[0032] The polyurethane foam of the present invention is prepared by synergistically combining a flame-retardant rigid foam polyol, a flame-retardant polyester polyol, a flame retardant, a catalyst, a foam stabilizer, an antioxidant and an open-cell agent, and then reacting with MDI to obtain a rigid polyurethane material. Among them, at least two flame retardants are used in combination, and at least three catalysts are used in combination. Through the optimization of the flame-retardant rigid foam polyol and polyester, a complete formulation system is obtained after full-water foaming. The density of the prepared polyurethane material is between 17 and 19 kg / m 3 ³, the average sound absorption coefficient is between 0.79 and 0.82, the open-cell rate is above 97.5%, and the sound absorption performance is good; the oxygen index is above 28%, the flame height is below 95 mm, and the flame retardant grade is B2, with good flame retardant performance; the compressive strength is above 26 kPa, and the dimensional change rate is below 0.15%, with more stable dimensions and no shrinkage. It can be seen that the polyurethane foam of the present invention has the advantages of high flame retardancy and dimensional stability on the premise of maintaining good sound absorption performance, overcoming the technical barriers such as foam collapse, foam shrinkage and non-forming easily caused by the combination of full-water foaming and flame-retardant raw materials in the prior art. Good technical effects have been achieved when used in polyurethane foam spraying. Detailed Embodiments

[0033] The present invention will be further described below through examples, but not limited to these examples.

[0034] Raw Material List

[0035] Rigid Foam Polyol:

[0036]

[0037]

[0038] Polyester Polyol:

[0039]

[0040] Foam stabilizer:

[0041] Raw material name Manufacturer B1048 Evonik Specialties (Shanghai) Co., Ltd. L-6900 Momentive Performance Materials Inc. AK-8805 Nanjing Dermission Chemical Co., Ltd. AK-6688 Nanjing Dermission Chemical Co., Ltd.

[0042] Catalyst:

[0043]

[0044] Flame retardant:

[0045]

[0046]

[0047] Cell opener:

[0048] Raw material name Manufacturer Ortegol 501 Evonik Specialties (Shanghai) Co., Ltd. AK-9901 Nanjing Dermission Chemical Co., Ltd.

[0049] Antioxidant:

[0050] Raw material name Manufacturer 1035 BASF SE 1010 BASF SE

[0051] Polymethylene polyphenyl polyisocyanate:

[0052] Raw material name Manufacturer M20S BASF SE PM-200 Yantai Wanhua Polyurethanes Co., Ltd.

[0053]

Example 1

[0054] (1) Preparation of Component A

[0055] By weight, in container A, add 15 parts of polyester polyol HF-8730, 7.1 parts of rigid foam polyol CNP-8119, 30 parts of TCPP, 38 parts of TDCPP, 0.6 part of foam stabilizer B1048, 1.4 parts of Polycat 5, 0.6 part of Polycat41, 0.5 part of Niax A-33, 6 parts of H2O, 0.2 part of cell opener Ortegol 501, and 0.6 part of antioxidant 1035, and stir for 1 hour to obtain Component A;

[0056] (2) Preparation of Component B

[0057] In container B, add 103 parts of M20S by weight and stir for 10 minutes to obtain Component B;

[0058] (3) Spray and construct Component A and Component B through a high-pressure spraying foaming machine. The operating conditions are: the pressure of the equipment is 1900 psi and the temperature is 26 °C; when spraying, the spray gun speed swings evenly. The constructed material is cured at room temperature for 24 h to obtain a rigid polyurethane material, and its performance index data is shown in Table 3.

[0059]

Examples 2 - 8

[0060] Examples 2 - 8 were carried out according to each step in Example 1, with the differences being different reaction raw materials, stirring times, raw material ratios, and operating conditions. See Table 1 for details; the performance index data of the rigid polyurethane materials prepared are shown in Table 3.

[0061] Table 1 Weight parts of each component raw material in Examples 1 - 8

[0062]

[0063]

[0064]

Comparative Examples 1 - 3

[0065] Comparative Examples 1 - 3 were carried out according to each step in Example 1, with the differences being different reaction raw materials and raw material ratios. See Table 2 for details; the performance index data of the rigid polyurethane materials prepared are shown in Table 4.

[0066] Table 2 Weight parts of each component raw material in Comparative Examples 1 - 3

[0067] Raw material components Comparative Example 1 Comparative Example 2 Comparative Example 3 PS-3152 15 15 15 WSFR-6 10 / / FR-600 / 10 / XOL B251 / / 10 TCPP 63 / 33 TEP / / 30 TCEP / 63 / Polycat 5 1.4 1.4 1.4 Polycat 41 0.5 0.5 0.5 Dabco T-12 0.3 0.3 0.3 Niax A-33 1 1 1 AK-6688 0.6 0.6 0.6 Ortegol 501 0.2 0.2 0.2 <![CDATA[H2O]]> 8 8 8 M20S 103 103 103

[0068] Table 3 Performance index data of the rigid polyurethane materials in Examples 1 - 8

[0069]

[0070]

[0071] Table 4 Performance index data of the rigid polyurethane materials in Comparative Examples 1 - 3

[0072]

[0073] As can be seen from Tables 3 and 4, the densities of Examples 1 - 8 and Comparative Examples 1 - 3 are all between 17 - 19 kg / m 3 and their thermal conductivity coefficients and compressive strengths are similar. However, the average sound absorption coefficients of Examples 1 - 8 are 0.79 - 0.82, the open cell rate is above 97.5%, and the sound absorption performance is better; the oxygen index is above 28%, the flame height is below 95 mm, the flame retardant grade is B2, and the flame retardant performance is better; the dimensional change rate is below 0.15%, the dimensions are more stable and do not shrink; all meet the industry standards for the roof spraying of Yutong buses, and the performance is superior to that of Comparative Examples 1 - 3.

[0074] It can be seen that on the premise of having good sound absorption performance, the rigid polyurethane material of the present invention also has the advantages of high flame retardancy and more stable dimensions, overcoming the technical barriers such as foam collapse, foam shrinkage, and non-formation that are easily caused when using all-water foaming and flame-retardant raw materials in the prior art, achieving good technical effects, and can be used in the bus spraying industry.

Claims

1. A rigid polyurethane material is composed of component A and component B. The weight ratio of component A to component B is 100:100 - 110. Component A, by weight, consists of 5 - 15 parts of polyester polyol, 5 - 10 parts of rigid foam polyol, 68 - 76 parts of flame retardant, 0.5 - 1.0 part of foam stabilizer, 2 - 4 parts of catalyst, 5 - 8 parts of water, 0.2 - 0.4 part of cell opener, and 0.5 - 1.5 parts of antioxidant; among which, The polyester polyol described is a flame-retardant polyester polyol with an average molecular weight of 400 to 500, a functionality of 2 to 3, and a hydroxyl value of 200 to 260 mgKOH / g; the rigid foam polyol described is a flame-retardant polyol with an average molecular weight of 400 to 650, a functionality of 2 to 3, and a hydroxyl value of 200 to 300 mgKOH / g; the flame retardant is selected from at least two of phosphate ester flame retardants; the foam stabilizer is selected from at least one of non-hydrolyzable silicon-carbon surfactants or polysiloxane surfactants; the catalyst is selected from at least two of Niax A-33 and Polycat 5, Polycat 41, Dabco T-12, Dabco K-15 or Niax A-1; Component B is polymethylene polyphenyl polyisocyanate; the polyester polyol is selected from at least one of HF-8730, Terol 250 or PS-7001.

2. The rigid polyurethane material according to claim 1, characterized in that, The rigid foam polyol described is selected from at least one of CNP-8119, Saytex RB-79 or XOL M125.

3. The rigid polyurethane material according to claim 2, wherein The rigid foam polyol CNP-8119 is prepared by the following steps: (1) Melamine, paraformaldehyde, methanol and diethanolamine are added to a reaction vessel in a molar ratio of 1:6:9:3, and stirred evenly to obtain Material I; (2) Material I reacts under normal pressure, the reaction temperature is 55 °C, and the reaction time is 3 h to obtain Material II; (3) Diethyl phosphite is added dropwise to Material II, the dropping time is 1 h, and the molar ratio of the added diethyl phosphite to the melamine in step (1) is 3:1 to obtain Material III; (4) Material III is heated to 75 °C, and a phosphoric acid aqueous solution with a mass percentage concentration of 30% is added to adjust the pH value to 4.0, and the reaction continues for 3 h to obtain Material IV; (5) After the reaction is completed, a sodium hydroxide aqueous solution with a mass percentage concentration of 30% is added to Material IV to adjust the pH value to 7.5, and small molecule by-products are removed by vacuum distillation. The vacuum distillation temperature is 75 °C and the pressure is -0.098 MPa, in terms of gauge pressure. After filtering to remove solid salts, the rigid foam polyol CNP-8119 is obtained.

4. The rigid polyurethane material according to claim 1, characterized in that, The flame retardant is selected from at least two of tris(2-chloroethyl) phosphate, tris(2-chloropropyl) phosphate, tris(dichloropropyl) phosphate or triethyl phosphate.

5. The rigid polyurethane material according to claim 1, wherein The cell opener is selected from at least one of Ortegol501 or AK-9901; the antioxidant is selected from at least one of 1035 or 1010; the foam stabilizer is selected from at least one of B-1048, L-6900 or AK-8805.

6. A method for preparing the rigid polyurethane material according to claim 1, comprising the following steps: (1) Prepare raw materials according to the following component weight parts: Component A consists of 5 - 15 parts by weight of polyester polyol, 5 - 10 parts by weight of rigid foam polyol, 68 - 76 parts by weight of flame retardant, 0.5 - 1.0 part by weight of foam stabilizer, 2 - 4 parts by weight of catalyst, 5 - 8 parts by weight of water, 0.2 - 0.4 part by weight of cell opener, and 0.5 - 1.5 parts by weight of antioxidant; among them, the polyester polyol is a flame - retardant polyester polyol with an average molecular weight of 400 - 500, a functionality of 2 - 3, and a hydroxyl value of 200 - 260 mgKOH / g; the rigid foam polyol is a flame - retardant polyol with an average molecular weight of 400 - 650, a functionality of 2 - 3, and a hydroxyl value of 200 - 300 mgKOH / g; the flame retardant is selected from at least two of phosphate - based flame retardants; the foam stabilizer is selected from at least one of non - hydrolyzable silicon - carbon - based surfactants or polysiloxane - type surfactants; the catalyst is selected from at least two of Niax A - 33, 5.Polycat 5, Polycat 41, Dabco T - 12, Dabco K - 15, or Niax A - 1; Component B is polymethylene polyphenyl polyisocyanate; the weight ratio of Component A to Component B is 100:100 - 110; (2) Preparation of Component A According to the components and weight parts in step (1), all raw materials in Component A are successively added into container A and stirred at room temperature for 1 - 1.5 hours to be fully mixed, obtaining Component A; (3) Preparation of Component B According to the weight parts of the components in step (1), polymethylene polyphenyl polyisocyanate is added into container B and stirred for 5 - 15 minutes to obtain Component B; (4) Component A and Component B are atomized and foamed through a high - pressure spraying foam machine, and after the foam is formed, it is cured to obtain a rigid polyurethane material.

7. The preparation method of the rigid polyurethane material according to claim 6, characterized in that, The operating conditions of the high - pressure spraying foam machine are as follows: the pressure of the equipment is 1600 - 2100 psi, the temperature is 25 - 30 °C; the spray gun speed swings evenly during spraying; the construction environment temperature is not lower than 15 °C, the relative humidity is less than 85%, the wind force is not greater than level 3, and the spraying thickness of each layer is controlled within 20 mm.

8. The preparation method of the rigid polyurethane material according to claim 6, characterized in that, The polyester polyol is selected from at least one of HF - 8730, Terol 250, or PS - 7001; the rigid foam polyol is selected from at least one of CNP - 8119, Saytex RB - 79, or XOL M125; the flame retardant is selected from at least two of tris(2 - chloroethyl) phosphate, tris(2 - chloropropyl) phosphate, tris(dichloropropyl) phosphate, or triethyl phosphate.

9. Application of the rigid polyurethane material according to claim 1 in the spraying of bus bodies.

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