Phenolic foam plastic and preparation method thereof

Abstract

The invention provides phenolic foam plastic and a preparation method thereof. The phenolic foam plastic comprises phenolic resin, boric acid, sodium sulfate, an organic silicon foam stabilizer, water and an acid catalyst. Wherein boric acid has double functions of flame retardance and enhancement, the crosslinking density of the phenolic resin is improved through chemical bonding, and the mechanical strength and the flame retardant grade are improved; the sodium sulfate is used as a nucleating agent to promote uniform refining of foam holes, reduce foam density and improve the percentage of closed area and the heat transfer coefficient; the organic silicon foam stabilizer is used for reducing the surface tension of a system, stabilizing a foam structure and avoiding cell collapse; water is used as the only foaming agent, the foaming rate is accurately regulated and controlled in combination with the acid catalyst, and flammable and explosive or fluorine-containing foaming agents are prevented from being used. The phenolic foam plastic disclosed by the invention is excellent in performance: the compression strength is more than or equal to 150kPa, the heat conductivity coefficient is less than or equal to 0.025 W / (m.K), and the vertical combustion reaches B1 level.

Description

Technical Field

[0001] This invention relates to the field of thermal insulation materials technology, and in particular to a phenolic foam plastic and its preparation method. Background Technology

[0002] Phenolic foam is widely used due to its flame retardancy, low thermal conductivity, and high temperature resistance, but existing technologies have the following shortcomings:

[0003] Traditional foaming agents and process problems: Fluorinated foaming agents (such as HFCs) damage the ozone layer, and organic foaming agents (such as n-pentane and petroleum ether) are flammable, explosive, and volatile, polluting the environment;

[0004] Limitations of all-water foaming technology: Existing formulas have problems such as large pores, high heat transfer coefficient, and poor mechanical properties, resulting in insufficient environmental protection and safety;

[0005] Insufficient synergistic effect of components: It is difficult to achieve the desired balance between cell structure, mechanical strength and flame retardant properties when using boric acid or sodium sulfate alone.

[0006] Existing patents (such as CN105367814A and CN101880365A) can only reduce the amount of foaming agent used, but cannot completely eliminate the addition of organic foaming agents. Technical solutions that completely eliminate the addition of organic foaming agents utilize ultrasonic foaming technology, which requires expensive equipment and increases production costs. Furthermore, while eliminating the addition of organic foaming agents, it is difficult to reduce the density of phenolic foam to below 55 kg / m³.

[0007] Therefore, developing a high-performance, all-water-blown phenolic foam that does not contain fluorinated or organic foaming agents has become a key technical challenge in the industry. Summary of the Invention

[0008] In view of this, the present invention provides a phenolic foam plastic and a method for preparing the same, in order to solve or at least partially solve the defects of the prior art.

[0009] To solve the above problems, the present invention adopts the following technical solution:

[0010] In a first aspect, the present invention provides a phenolic foam plastic comprising the following components in parts by weight: 100 parts of phenolic resin, 5-15 parts of boric acid, 4-12 parts of sodium sulfate, 15-20 parts of organosilicon foam stabilizer, 1-3 parts of water, and 1-3 parts of acidic catalyst.

[0011] Preferably, the acidic catalyst includes hydrochloric acid and p-toluenesulfonic acid.

[0012] Preferably, the mass ratio of hydrochloric acid to p-toluenesulfonic acid is (0.5~2):(0.5~2).

[0013] Preferably, the hydrochloric acid has a mass fraction of 30-36%.

[0014] Preferably, the composition includes the following components in parts by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-12 parts sodium sulfate, 15-20 parts organosilicon foam stabilizer, 1-3 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0015] Preferably, the composition includes the following components in parts by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0016] Preferably, the composition includes the following components in parts by weight: 100 parts phenolic resin, 10 parts boric acid, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0017] Secondly, the present invention also provides a method for preparing the aforementioned phenolic foam plastic, comprising the following steps:

[0018] A mixture is obtained by mixing phenolic resin with boric acid, sodium sulfate, and organosilicon foam stabilizer.

[0019] Add an acidic catalyst and water to the mixture, and continue stirring to obtain a foam.

[0020] The foam is cured to obtain phenolic foam plastic.

[0021] Preferably, the curing temperature is 110~140℃ and the curing time is 2~5h.

[0022] The phenolic foam plastic and its preparation method of the present invention have the following advantages over the prior art:

[0023] The phenolic foam plastic of this invention comprises phenolic resin, boric acid, sodium sulfate, organosilicon foaming agent, water (as a foaming agent), and an acidic catalyst. Boric acid serves both flame-retardant and reinforcing functions, increasing the crosslinking density of the phenolic resin through chemical bonding, thereby improving mechanical strength and flame retardancy. Sodium sulfate (anhydrous sodium sulfate) acts as a nucleating agent, promoting uniform and refined cell structure, reducing foam density, and improving closed-cell ratio and heat transfer coefficient. The organosilicon foaming agent reduces the surface tension of the system, stabilizes the foam structure, and prevents cell collapse. The all-water foaming system uses water as the sole foaming agent, combined with an acidic catalyst (hydrochloric acid plus p-toluenesulfonic acid) to precisely control the foaming rate, avoiding the use of flammable, explosive, or fluorinated foaming agents. The phenolic foam plastic of this invention has the following specific technical advantages: Environmental advantages: It does not contain flammable, explosive, or volatile foaming agents such as n-pentane, cyclopentane, and petroleum ether; it does not contain ozone-depleting fluorinated foaming agents. Excellent performance: compressive strength ≥150kPa, thermal conductivity ≤0.025W / (m·K), vertical combustion rating up to B1. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that the order of description of the following embodiments is not intended to limit the preferred order of embodiments. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a rigid limitation on the scope of the invention; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single digits within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any referenced number (fraction or integer) within the indicated range.

[0026] This application provides a phenolic foam plastic comprising the following components in parts by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-12 parts sodium sulfate, 15-20 parts organosilicon foam stabilizer, 1-3 parts water, and 1-3 parts acidic catalyst.

[0027] The phenolic foam plastic of the present invention comprises phenolic resin, boric acid, sodium sulfate, organosilicon foaming agent, water (as a foaming agent), and an acidic catalyst; wherein the functions of each raw material are as follows:

[0028] Boric acid has both flame-retardant and reinforcing functions. It improves the cross-linking density of phenolic resin through chemical bonding, thereby enhancing mechanical strength and flame-retardant rating.

[0029] Sodium sulfate (anhydrous sodium sulfate): as a nucleating agent, it promotes uniform and refined cell structure, reduces foam density, and improves closed-cell ratio and heat transfer coefficient.

[0030] Organosilicon foam stabilizer: reduces the surface tension of the system, stabilizes the foam structure, and prevents cell collapse;

[0031] All-water foaming system: Water is used as the sole foaming agent, and the foaming rate is precisely controlled by an acidic catalyst (hydrochloric acid and p-toluenesulfonic acid), avoiding the use of flammable, explosive or fluorinated foaming agents.

[0032] The phenolic foam of the present invention has the following specific technical advantages:

[0033] Environmental advantages: Free from flammable, explosive, and volatile foaming agents such as n-pentane, cyclopentane, and petroleum ether; free from ozone-depleting fluorinated foaming agents.

[0034] Excellent performance: compressive strength ≥150kPa, thermal conductivity ≤0.025W / (m·K), vertical combustion rating up to B1.

[0035] In some embodiments, the acidic catalyst includes hydrochloric acid and p-toluenesulfonic acid.

[0036] In some embodiments, the mass ratio of hydrochloric acid to p-toluenesulfonic acid is (0.5~2):(0.5~2).

[0037] In some embodiments, hydrochloric acid refers to an aqueous solution of hydrochloric acid with a mass fraction of 30-36%.

[0038] In some embodiments, the silicone foam stabilizer is a polyether-modified silicone oil.

[0039] In some embodiments, the product comprises the following components in parts by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-12 parts sodium sulfate, 15-20 parts organosilicon foam stabilizer, 1-3 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0040] In some embodiments, the product comprises the following components in parts by weight: 100 parts phenolic resin, 10-15 parts boric acid, 4-12 parts sodium sulfate, 15-20 parts organosilicon foam stabilizer, 1-3 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0041] In some embodiments, the product comprises the following components in parts by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0042] In some embodiments, the product comprises the following components in parts by weight: 100 parts phenolic resin, 10-15 parts boric acid, 4-8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0043] In some embodiments, the product comprises the following components in parts by weight: 100 parts phenolic resin, 10 parts boric acid, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid.

[0044] Based on the same inventive concept, the present invention also provides a method for preparing the above-mentioned phenolic foam plastic, comprising the following steps:

[0045] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0046] S2. Add acidic catalyst and water to the mixture and continue stirring to obtain foam.

[0047] S3. The foam is cured to obtain phenolic foam plastic.

[0048] In some embodiments, the curing temperature is 110~140℃ and the curing time is 2~5h.

[0049] The following detailed embodiments further illustrate the phenolic foam plastic and its preparation method of this application. This section further explains the invention in conjunction with specific embodiments, but should not be construed as limiting the invention. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art. Unless otherwise specified, the reagents, methods, and equipment used in this invention are conventional reagents, methods, and equipment in the art.

[0050] In the following examples and comparative examples, the phenolic resin brand is Kafman, and the grade is phenolic resin 2130.

[0051] In the following examples and comparative examples, the silicone foam stabilizer was purchased from Hubei Longsheng Sihai New Materials Co., Ltd., specifically a polyether-modified silicone oil, specification SH-204.

[0052] Example 1

[0053] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0054] 100 parts phenolic resin, 10 parts boric acid, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, hydrochloric acid aqueous solution with a mass fraction of 36%).

[0055] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0056] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0057] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0058] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0059] Example 2

[0060] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0061] 100 parts phenolic resin, 5 parts boric acid, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, hydrochloric acid aqueous solution with a mass fraction of 36%).

[0062] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0063] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0064] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0065] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0066] Example 3

[0067] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0068] 100 parts phenolic resin, 15 parts boric acid, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, hydrochloric acid aqueous solution with a mass fraction of 36%).

[0069] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0070] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0071] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0072] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0073] Example 4

[0074] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0075] 100 parts phenolic resin, 10 parts boric acid, 4 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, hydrochloric acid aqueous solution with a mass fraction of 36%).

[0076] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0077] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0078] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0079] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0080] Example 5

[0081] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0082] 100 parts phenolic resin, 10 parts boric acid, 12 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, hydrochloric acid aqueous solution with a mass fraction of 36%).

[0083] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0084] S1. Phenolic resin is mixed with boric acid, sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0085] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0086] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0087] Comparative Example 1 (without sodium sulfate)

[0088] This comparative example provides a phenolic foam plastic comprising the following components in parts by weight:

[0089] 100 parts phenolic resin, 10 parts boric acid, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, an aqueous solution of hydrochloric acid with a mass fraction of 36%).

[0090] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0091] S1. Mix phenolic resin with boric acid and organosilicon foam stabilizer to obtain a mixture;

[0092] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0093] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0094] Comparative Example 2 (without boric acid)

[0095] This application provides a phenolic foam plastic, comprising the following components in parts by weight:

[0096] 100 parts phenolic resin, 8 parts sodium sulfate, 18 parts organosilicon foam stabilizer, 2 parts water, 1 part p-toluenesulfonic acid, and 1 part hydrochloric acid (specifically, an aqueous solution of hydrochloric acid with a mass fraction of 36%).

[0097] The preparation method of the above-mentioned phenolic foam includes the following steps:

[0098] S1. Phenolic resin is mixed with sodium sulfate and organosilicon foam stabilizer to obtain a mixture;

[0099] S2. Add acidic catalyst (p-toluenesulfonic acid and hydrochloric acid) and water to the mixture, and continue stirring to obtain a foam.

[0100] S3. Cure the foam at 120℃ for 3 hours to obtain phenolic foam plastic.

[0101] Performance testing

[0102] The density (apparent (volume) density of foamed plastics) prepared in Examples 1-5 and Comparative Examples 1-2 was determined using the national standard GB / T 6343-1995 Determination of apparent (volume) density of foamed plastics and rubber, thermal conductivity (heat flow meter method for determination of steady-state heat transfer characteristics of insulating materials) was tested, compressive strength (compression test method for rigid foamed plastics) was determined using the national standard GB / T 8813-1988, and combustion performance (classification method for combustion performance of building materials) was determined using the national standard GB 8624-1997. The test results are shown in Table 1 below.

[0103] Table 1 - Properties of phenolic foams prepared in Examples 1-5 and Comparative Examples 1-2

[0104]

[0105] As shown in Table 1, the phenolic foam prepared in Examples 1, 3-5 of this invention has a compressive strength ≥150 kPa, a thermal conductivity ≤0.025 W / (m•K), and achieves a B1 fire rating in vertical combustion. Considering factors such as density, thermal conductivity, and compressive strength, the phenolic foam prepared in Example 1 has the best performance; the phenolic foam prepared in Example 3 has the highest compressive strength; the phenolic foam prepared in Examples 2 and 5 has a relatively low density; in general, a higher content of sodium sulfate (i.e., anhydrous sodium sulfate) results in a lower density of phenolic foam; and a higher content of boric acid results in better mechanical properties of phenolic foam.

[0106] Application effect verification: The phenolic foam plastic prepared in Example 1 was used for building exterior wall insulation. Compared with commercially available fluorinated foamed phenolic foam, the thermal conductivity was reduced by 10%, the fire rating was improved to B1, the cost was reduced by 15%, and no harmful gases were released.

[0107] It is understood that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0108] The above are merely preferred embodiments of this application, and only specifically describe the technical principles of this application. These descriptions are only for explaining the principles of this application and should not be construed as limiting the scope of protection of this application in any way. Based on this explanation, any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application, as well as other specific embodiments of this application that can be conceived by those skilled in the art without creative effort, should be included within the scope of protection of this application.

Claims

1. A phenolic foam plastic, characterized in that, It includes the following components by weight: 100 parts phenolic resin, 5-15 parts boric acid, 4-12 parts sodium sulfate, 15-20 parts organosilicon foam stabilizer, 1-3 parts water, and 1-3 parts acidic catalyst.

2. The phenolic foam plastic as described in claim 1, characterized in that, The acidic catalysts include hydrochloric acid and p-toluenesulfonic acid.

3. The phenolic foam plastic as described in claim 2, characterized in that, The mass ratio of hydrochloric acid to p-toluenesulfonic acid is (0.5~2):(0.5~2).

4. The phenolic foam plastic as described in claim 2, characterized in that, The hydrochloric acid has a mass fraction of 30-36%.

5. A method for preparing phenolic foam plastic as described in any one of claims 1 to 4, characterized in that, Includes the following steps: A mixture is obtained by mixing phenolic resin with boric acid, sodium sulfate, and organosilicon foam stabilizer. Add an acidic catalyst and water to the mixture, and continue stirring to obtain a foam. The foam is cured to obtain phenolic foam plastic.

6. The method for preparing phenolic foam plastic as described in claim 5, characterized in that, The curing temperature is 110~140℃ and the time is 2~5h.

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