Foaming material for polyurethane material as well as preparation method and application of foaming material

Abstract

The invention relates to the technical field of high-molecular polyurethane foaming materials, and provides a foaming material for a polyurethane material and a preparation method and application thereof.The foaming material is prepared from, by weight, 60-80 parts of methyl tertiary butyl ether, 10-20 parts of a foaming agent, 0.5-2 parts of a foaming stabilizer, 2-5 parts of a catalyst, 4-10 parts of a composite flame retardant and 0.5-3 parts of glycerin; and 1-5 parts of water. The foaming material for the polyurethane material provided by the invention has the characteristics of good foaming performance and flame retardance, and can be widely applied to the field of building thermal insulation.

Description

Technical Field

[0001] The invention relates to the technical field of foaming materials, and in particular to a foaming material for polyurethane materials, a preparation method and application thereof. Background Art

[0002] As an important organic polymer material, polyurethane material has good elasticity, wear resistance, tear resistance and aging resistance, and is widely used in light industry, chemical industry, construction and other fields. Especially in the field of construction, the polyurethane foam material obtained by applying foaming materials with good foaming properties to polyurethane is an ideal thermal insulation material with excellent thermal insulation functions. Its excellent thermal insulation performance can effectively prevent the transfer of heat, reduce the energy consumption of buildings, achieve the goal of energy conservation and emission reduction, and provide users with a more comfortable and energy-saving living and working environment.

[0003] Although the application of foaming materials makes polyurethane foaming materials have good application prospects in the field of thermal insulation, ordinary polyurethane materials have poor high temperature resistance and are easy to burn, which poses a great safety hazard when used. In recent years, fire accidents caused by polyurethane wall insulation materials have occurred frequently. Therefore, for safety reasons, foaming materials need to have certain flame retardancy in addition to good foaming performance. People often add flame retardants to foaming materials, but traditional flame retardants have problems with high smoke production and toxicity, and some solid flame retardants also have the problem of poor dispersion in the resin matrix.

[0004] Patent CN 115322323 A discloses a polyurethane thermal insulation material and a preparation method thereof. The polyurethane thermal insulation material includes components such as polypropylene carbonate polyol, diisocyanate, catalyst, chain extender, stabilizer, flame retardant, etc., and has good foam density, i.e. foaming performance and mechanical properties. However, the flame retardant properties of the polyurethane thermal insulation material are not measured and characterized in the application. Although ammonium polyphosphate and / or melamine are selected as the flame retardant, and a small amount of triethanolamine dispersant is contained in the application, ammonium polyphosphate and melamine themselves are very easy to agglomerate, and even if triethanolamine is used, it is still difficult to completely eliminate the agglomeration phenomenon, which may cause the flame retardancy of the polyurethane thermal insulation material to fail to reach an ideal level.

[0005] Therefore, there is an urgent need in the market for a foaming material for polyurethane materials that has both good foaming performance and flame retardancy. Summary of the invention

[0006] In view of the problems existing in the prior art, the present invention uses methyl tert-butyl ether and a foaming agent as main raw materials and designs and adds a composite flame retardant to synthesize a foaming material for polyurethane material, which has good foaming performance and high flame retardancy.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0008] On one hand, the present invention provides a foaming material for polyurethane material, which comprises the following raw materials: 60-80 parts of methyl tert-butyl ether, 10-20 parts of foaming agent, 0.5-2 parts of foaming stabilizer, 2-5 parts of catalyst, 4-10 parts of composite flame retardant, 0.5-3 parts of glycerol and 1-5 parts of water.

[0009] In some embodiments of the present invention, the blowing agent is a pentane blowing agent.

[0010] Preferably, the pentane blowing agent is any one of n-pentane, isopentane and cyclopentane.

[0011] In some embodiments of the present invention, the foam stabilizer is polysiloxane.

[0012] In some embodiments of the present invention, the catalyst is a tertiary amine catalyst.

[0013] Preferably, the catalyst is PT303.

[0014] In some embodiments of the present invention, the composite flame retardant is a mixture of modified PAPP and TCPP in a mass ratio of 1:(0.6-1).

[0015] More preferably, the composite flame retardant is a mixture of modified PAPP and TCPP in a mass ratio of 1:0.8.

[0016] The applicant compounded modified PAPP and TCPP in a certain mass ratio to form a composite flame retardant. PAPP has good charring and gas phase inhibition, while TCPP mainly plays a flame retardant role by promoting charring in the condensed phase and capturing free radicals in the gas phase. The two have certain complementarity in flame retardant mechanism, which can synergistically enhance the flame retardant performance and have a good inhibitory effect on the flammability and explosion of pentane foaming agent. In addition, the applicant uses solid flame retardant (modified PAPP) and liquid flame retardant (TCPP) in combination, which can also alleviate the problem of poor dispersion of solid flame retardant in resin matrix to a certain extent.

[0017] In some embodiments of the present invention, the method for preparing the modified PAPP comprises the following steps:

[0018] (1) adding allyl trimethyl ammonium chloride to anhydrous ethanol, stirring, adding oxalic acid, stirring at 70-90° C. to obtain a solution for use; adding camellia oleifera shell powder to the solution, microwave treatment at 145-155° C. for 10-20 min, distilling under reduced pressure, adding deionized water while stirring, centrifuging, washing, and freeze-drying the precipitate to obtain camellia oleifera shell-based lignin for use;

[0019] (2) mixing boehmite and the camellia oleifera shell-based lignin obtained in step (1), ball milling, adding PAPP, stirring, then adding silicone masterbatch, stirring at high speed, and drying to obtain modified PAPP.

[0020] Wherein, in the step (1), the mass ratio of camellia oleifera shell powder, allyltrimethylammonium chloride and oxalic acid is 1:(0.4-0.8):(0.2-0.6).

[0021] In some embodiments of the present invention, in step (2), the mass ratio of PAPP, boehmite and tea nut shell-based lignin is 1: (0.03-0.07): (0.2-0.3).

[0022] Preferably, in step (2), the mass ratio of PAPP, boehmite and camellia oleifera shell-based lignin is 1:0.05:0.25.

[0023] In some embodiments of the present invention, in step (2), the average particle size of the silicone masterbatch is 5-10 μm.

[0024] In some embodiments of the present invention, in step (2), the mass ratio of PAPP to silicone masterbatch is 1:(0.01-0.04).

[0025] Preferably, in step (2), the mass ratio of PAPP to silicone masterbatch is 1:0.025.

[0026] PAPP has excellent charring properties and flame retardant effects due to the integration of acid source, carbon source and gas source in its molecular structure. The piperazine molecular structure is similar to the benzene ring, which gives it outstanding thermal stability. In addition, PAPP also has a certain role as a foaming agent. Its application in foaming materials has good application prospects. However, the current preparation method of PAPP has the disadvantages of low yield, high impurities and high cost, and the van der Waals force between its particles makes it easy to agglomerate. These defects will affect its improvement of the flame retardant properties of polyurethane foam materials.

[0027] The applicant first uses camellia oleifera shell as raw material, extracts lignin in an acidic low eutectic solvent prepared by allyltrimethylammonium chloride as a hydrogen bond acceptor and oxalic acid as a hydrogen bond donor, and obtains camellia oleifera shell-based lignin through microwave and freeze-drying treatment. The camellia oleifera shell-based lignin prepared by this method has the characteristics of small particle size, excellent stability and good dispersibility. Furthermore, the applicant mixes boehmite and camellia oleifera shell-based lignin by ball milling and then compounds them with PAPP. Boehmite is a layered inorganic nanofiller that can absorb heat and release flame-retardant gas when heated. The substances produced by decomposition can play a role in reinforcing the carbon layer, thereby playing a synergistic role in flame retardancy. Camellia oleifera shell-based lignin contains rich hydroxyl and aromatic functional groups, meets the structural requirements of a macromolecular carbonizing agent, and can also cooperate with PAPP to simultaneously release carbon in the gas phase and the condensed phase. In addition, the applicant unexpectedly discovered that ball-milling mixing of boehmite and tea husk-based lignin can greatly improve the flame retardancy of PAPP. It is speculated that the reason is that hydrogen bonds can be formed between the hydroxylated aluminum-oxygen bonds on the surface of boehmite and the abundant hydroxyl groups on the surface of tea husk-based lignin, thereby enhancing the interfacial bonding force, thereby making the modified PAPP more stable, and thus effectively improving the flame retardancy of PAPP; finally, the applicant added silicone masterbatch with an average particle size of 5-10 μm to further modify the dispersibility of PAPP. The reason is that the small-sized silicone masterbatch can form an effective interval between the PAPP particles, thereby achieving the effect of dispersing and weakening the inter-particle force, thereby increasing the fluidity of the modified PAPP and reducing agglomeration, thereby enabling the modified PAPP to be effectively dispersed in the matrix.

[0028] Another aspect of the present invention further provides a method for preparing a foaming material for a polyurethane material according to the above technical solution, comprising the following steps:

[0029] Mix methyl tert-butyl ether, a foaming agent, a foaming stabilizer, a composite flame retardant, glycerin and water, stir for 15-25 minutes, add a catalyst, and stir for 1-2 hours to obtain a foaming material for a polyurethane material.

[0030] Another aspect of the present invention further provides the application of the foaming material for polyurethane material described in the above technical solution, which is applied to the field of building thermal insulation.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The present invention uses methyl tert-butyl ether and pentane foaming agent as main raw materials, and designs and adds a composite flame retardant to synthesize a foaming material for polyurethane material. Through the synergistic effect between the components, it has good foaming performance and high flame retardancy, and can be widely used in the field of building insulation.

[0033] (2) The present invention firstly prepares tea nut shell-based lignin with good dispersibility and stability by a specific method, and then mixes boehmite and tea nut shell-based lignin with PAPP after ball milling. Finally, a silicone masterbatch with a specific particle size is introduced to obtain modified PAPP, which effectively improves the dispersibility of PAPP. Then, it is compounded with TCPP to make the flame retardant properties of the two complement each other, thereby greatly improving the flame retardant properties of the composite flame retardant for polyurethane foam materials. DETAILED DESCRIPTION

[0034] The present invention will be described below in conjunction with specific embodiments. It should be noted that the following embodiments are examples of the present invention and are only used to illustrate the present invention, but not to limit the present invention. Other combinations and various modifications within the concept of the present invention may be performed without departing from the spirit or scope of the present invention.

[0035] In the following embodiments and comparative examples, except for the modified PAPP, the other compound monomers and related reagents used can be purchased from the market, wherein the foaming stabilizer is methyl silicone oil purchased from Qingdao Meiside Silicone Co., Ltd.; the catalyst is PT303 purchased from Beijing Huizhi Zhongcheng Science and Technology Trade Co., Ltd.; the phosphoric acid is 85% industrial grade phosphoric acid; the average particle size of the silicone masterbatch is 5 μm; the polyurethane matrix is ​​polyether polyurethane purchased from Dongguan Julong Plastic Raw Materials Co., Ltd.; the model of the polyether polyol is Shandong Bluestar Dongda T-403; the model of the polyester polyol is Qingdao Ruinuo Chemical PS-3152; the isocyanate is polymethylene polyphenyl polyisocyanate, model Dow PAPI-135C.

[0036] Preparation Example 1

[0037] The synthesis method of modified PAPP-1 comprises the following steps:

[0038] (1) Add 9 g of allyltrimethylammonium chloride to 30 ml of anhydrous ethanol, stir for 15 min, add 6 g of oxalic acid, stir at 80° C. for 30 min, and obtain a solution for use; add 15 g of camellia oleifera shell powder to the solution, microwave at 150° C. for 15 min, distill under reduced pressure, add 200 ml of deionized water while stirring, centrifuge, wash with deionized water 3 times, freeze-dry the precipitate at -60° C. for 72 h, and obtain camellia oleifera shell tea-based lignin for use;

[0039] (2) 2 g of boehmite and 10 g of tea-based lignin from step (1) were mixed, ball-milled for 5 min, 40 g of PAPP was added, stirred for 2 h, and then 1 g of silicone masterbatch was added. The mixture was stirred at 10,000 rpm for 30 min and dried at 105° C. for 30 min to obtain modified PAPP-1.

[0040] Preparation Example 2

[0041] The specific implementation method of modified PAPP-2 is the same as that of modified PAPP-1, except that in step (2), the mass of boehmite is replaced with 0.8 g.

[0042] Preparation Example 3

[0043] The specific implementation method of modified PAPPC-3 is the same as that of modified PAPPA-1, except that in step (2), the mass of camellia oleifera-based lignin is replaced with 7.2 g.

[0044] Preparation Example 4

[0045] The specific implementation method of modified PAPP-4 is the same as that of modified PAPP-1, except that in step (2), the mass of silicone masterbatch is replaced with 0.32 g.

[0046] Example 1

[0047] A foaming material for polyurethane material, the foaming material comprises the following raw materials by weight: 70 parts of methyl tert-butyl ether, 15 parts of n-pentane, 1.5 parts of methyl silicone oil, 3.5 parts of catalyst PT303, 7 parts of composite flame retardant, 2 parts of glycerol, and 3 parts of water;

[0048] The composite flame retardant is a mixture of modified PAPP-1 and TCPP with a mass ratio of 1:0.8.

[0049] The preparation method of the foaming material for polyurethane material in this embodiment comprises the following steps:

[0050] Methyl tert-butyl ether, n-pentane, foaming stabilizer, composite flame retardant, glycerin and water are mixed, stirred for 20 minutes, catalyst PT303 is added, and stirred for 1.5 hours to obtain a foaming material for a polyurethane material.

[0051] Example 2

[0052] A foaming material for polyurethane material, the foaming material comprises the following raw materials by weight: 60 parts of methyl tert-butyl ether, 10 parts of isopentane, 0.5 parts of methyl silicone oil, 2 parts of catalyst PT303, 4 parts of composite flame retardant, 0.5 parts of glycerin, and 1 part of water;

[0053] The composite flame retardant is a mixture of modified PAPP-1 and TCPP with a mass ratio of 1:0.6.

[0054] The preparation method of the foaming material for polyurethane material in this embodiment comprises the following steps:

[0055] Methyl tert-butyl ether, isopentane, methyl silicone oil, composite flame retardant, glycerin and water are mixed, stirred for 15 minutes, catalyst PT303 is added, and stirred for 1 hour to obtain a foaming material for a polyurethane material.

[0056] Example 3

[0057] A foaming material for polyurethane material, which comprises the following raw materials by weight: 80 parts of methyl tert-butyl ether, 20 parts of cyclopentane, 2 parts of methyl silicone oil, 5 parts of catalyst PT303, 10 parts of composite flame retardant, 3 parts of glycerol, and 5 parts of water;

[0058] The composite flame retardant is a mixture of modified PAPP-1 and TCPP with a mass ratio of 1:1.

[0059] The preparation method of the foaming material for polyurethane material in this embodiment comprises the following steps:

[0060] Methyl tert-butyl ether, cyclopentane, methyl silicone oil, composite flame retardant, glycerin and water are mixed, stirred for 25 minutes, catalyst PT303 is added, and stirred for 2 hours to obtain a foaming material for a polyurethane material.

[0061] Example 4

[0062] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the composite flame retardant is a mixture of modified PAPP-1 and TCPP, with a mass ratio of 1:0.4.

[0063] Example 5

[0064] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the composite flame retardant is a mixture of modified PAPP-1 and TCPP, with a mass ratio of 1:1.2.

[0065] Example 6

[0066] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified PAPP-2 replaces the modified PAPP-1 in equal amounts.

[0067] Example 7

[0068] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified PAPP-3 replaces the modified PAPP-1 in equal amounts.

[0069] Example 8

[0070] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that the modified PAPP-4 replaces the modified PAPP-1 in equal amounts.

[0071] Example 9

[0072] This embodiment provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation method is the same as that of Example 1, except that PAPP is used to replace the modified PAPP-1 in equal amounts.

[0073] Comparative Example 1

[0074] This comparative example provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that the composite flame retardant is replaced by an equal amount of modified PAPP-1.

[0075] Comparative Example 2

[0076] This comparative example provides a foaming material for polyurethane material and a preparation method thereof. The specific implementation manner is the same as that of Example 1, except that TCPP is used to replace the composite flame retardant in equal amounts.

[0077] Performance Testing

[0078] The flame retardancy of the polyurethane foam materials described in Examples 1-9 and Comparative Examples 1-2 was tested, and the test results are shown in Table 1.

[0079] The foaming materials prepared in Examples 1-9 and Comparative Examples 1-2 are mixed with polyol, isocyanate and a cross-linking agent to prepare a polyurethane foaming material. The preparation method comprises the following steps:

[0080] Mix 30g of polyether polyol, 10g of polyester polyol and 6g of foaming material, stir evenly, add 70g of isocyanate and 1g of pentaerythritol, stir evenly and inject into the mold, foam at 55°C, mature the foam at room temperature for 2h, and cure at 70°C for 2h to obtain a polyurethane foam material.

[0081] The flame retardant performance is judged by testing the oxygen index, referring to the standard GB / T 2046.2. The higher the oxygen index, the better the flame retardant performance.

[0082] Table 1

[0083] Group Oxygen index (%) Example 1 32.5 Example 2 32.3 Example 3 32.2 Example 4 31.6 Example 5 31.9 Example 6 31.2 Example 7 31.1 Example 8 30.8 Example 9 30.4 Comparative Example 1 30.1 Comparative Example 2 29.8

[0084] It can be seen from the data in Table 1 that the foaming materials for polyurethane materials in Examples 1-3 of the present invention have good flame retardancy as a whole, among which Examples 4-5 change the ratio between the composite flame retardant modified PAPP-1 and TCPP, so that the flame retardant synergistic effect between the two decreases, thereby causing the flame retardancy of the foaming material to decrease to a certain extent; Examples 6-8 change the modification ratio of boehmite, tea oil fruit tea-based lignin and silicone masterbatch to PAPP during the synthesis of modified PAPP, so that the flame retardancy and dispersibility of the modified PAPP are not well improved, thereby causing the flame retardant properties of the foaming material to decrease significantly; Example 9 is an equal replacement of PAPP for modified PAPP-1 by PAPP, and Comparative Examples 1-2 are equal replacements of the composite flame retardant by modified PAPP-1 and TCPP, respectively. It was found in the test that the flame retardancy of the foaming materials for polyurethane materials showed poor results.

[0085] The foaming properties of the polyurethane foam material obtained from the foaming materials of Examples 1-3 above were tested, and the test results are shown in Table 2.

[0086] The foaming performance is judged by testing the foam density. The polyurethane foam material is cut into a cube of 1cm×1cm×1cm. The length, width and height of the sample are accurately measured using a micrometer. Multiple measurements are required at different positions to find the average value and calculate the volume of the sample. The mass of the polyurethane foam material is then accurately weighed. The average value of the three weighings is taken as the final mass. Finally, the density of the measured sample is calculated.

[0087] Table 2

[0088] Group <![CDATA[Foam density (g / cm 3 )]]> Example 1 0.50 Example 2 0.52 Example 3 0.49

[0089] It can be seen from the data in Table 2 that the polyurethane foam materials in Examples 1-3 of the present invention all have suitable foam densities, which proves that the foam materials have good foaming properties.

[0090] The above implementation modes are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the content of the present invention and implement it, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A foaming material for polyurethane material, characterized in that: The foaming material comprises the following raw materials by weight: 60-80 parts of methyl tert-butyl ether, 10-20 parts of foaming agent, 0.5-2 parts of foaming stabilizer, 2-5 parts of catalyst, 4-10 parts of composite flame retardant, 0.5-3 parts of glycerol and 1-5 parts of water.

2. The foaming material for polyurethane material according to claim 1, characterized in that: The foaming agent is pentane foaming agent.

3. The foaming material for polyurethane material according to claim 1, characterized in that: The catalyst is a tertiary amine catalyst.

4. The foaming material for polyurethane material according to claim 1, characterized in that: The composite flame retardant is a mixture of modified PAPP and TCPP, with a mass ratio of 1:(0.6-1).

5. The foaming material for polyurethane material according to claim 4, characterized in that: The preparation method of the modified PAPP comprises the following steps: (1) adding allyl trimethyl ammonium chloride to anhydrous ethanol, stirring, adding oxalic acid, stirring at 70-90° C. to obtain a solution for use; adding camellia oleifera shell powder to the solution, microwave treatment at 145-155° C. for 10-20 min, distilling under reduced pressure, adding deionized water while stirring, centrifuging, washing, and freeze-drying the precipitate to obtain camellia oleifera shell-based lignin for use; (2) mixing boehmite and the camellia oleifera shell-based lignin obtained in step (1), ball milling, adding PAPP, stirring, then adding silicone masterbatch, stirring at high speed, and drying to obtain modified PAPP.

6. The foaming material for polyurethane material according to claim 5, characterized in that: In the step (2), the mass ratio of PAPP, boehmite and tea nut shell-based lignin is 1: (0.03-0.07): (0.2-0.3).

7. The foaming material for polyurethane material according to claim 5, characterized in that: In the step (2), the average particle size of the silicone masterbatch is 5-10 μm.

8. The foaming material for polyurethane material according to claim 7, characterized in that: In the step (2), the mass ratio of PAPP to silicone masterbatch is 1:(0.01-0.04).

9. A method for preparing a foaming material for a polyurethane material according to any one of claims 1 to 8, characterized in that: The following steps are involved: Mix methyl tert-butyl ether, a foaming agent, a foaming stabilizer, a composite flame retardant, glycerin and water, stir for 15-25 minutes, add a catalyst, and stir for 1-2 hours to obtain a foaming material for a polyurethane material.

10. An application of a foaming material for a polyurethane material according to any one of claims 1 to 8, characterized in that: Used in the field of building insulation.