KR100756272B1 - Preparation method of phenol resin form - Google Patents

Abstract

A method for preparing a phenolic resin foam is provided to improve the uniformity and fineness of cells and to enhance flame retardancy, heat insulation and mechanical strength by increasing the foaming time. A method for preparing a phenolic resin foam comprises the steps of mixing 100 parts by weight of a resol phenolic resin with 0.1-5 parts by weight of a nonionic surfactant and 5-50 parts by weight of a weak acidic curing agent to prepare a first solution; mixing 40-70 parts by weight of a polyol-based antifoaming agent, 0.1-5 parts by weight of a nonionic surfactant, 10-50 parts by weight of a hydrocarbon-based foaming agent and 10-30 parts by weight of an alkali metal carbonate-based auxiliary foaming agent based on 100 parts by weight of the resol phenolic resin to prepare a second solution; and mixing the first solution and the second solution by stirring with foaming at 80-110 deg.C for 5-10 min by the heat generated by the mixing.

Description

Preparation method of phenolic resin foam foam {Preparation method of phenol resin form}

The present invention relates to a method for preparing a phenolic resin foam, and more particularly, a solution prepared by mixing a resol type phenolic resin, a nonionic surfactant and a weakly acidic curing agent, and a polyol foam stabilizer, a nonionic surfactant, and a hydrocarbon. By preparing a solution prepared by mixing the blowing agent and the auxiliary foaming agent of the alkali metal carbonate, and performing the process of mixing the respective solutions, it is possible to foam at room temperature without a separate heat by the heat generated during the mixing, The foaming time is extended by the surfactant to form a uniform and finely sized cell of the foam, and the foam produced is highly suitable for interior and exterior materials and insulation materials in the building materials field due to improved flame retardancy, insulation, and mechanical strength. It relates to a method for producing a foam.

Styrofoam, urethane foam, glass fiber and epoxy resin insulators are the most common thermal insulation materials using foam foam, and their substrates are made of thermoplastic resins that are weak to heat, and thus are susceptible to fire. As styrofoam used as building materials, urethane foam insulation, and molding materials of various structures are made of combustible materials, fires are frequently generated both domestically and internationally. In order to solve the structural problem, the use of special materials imparting flame retardancy is essential. However, there is almost no production of heat-insulating material with good eco-friendliness and flame retardancy. In addition, glass fiber and asbestos insulation materials have been developed but are not widely used due to the results of research showing that the production price is high and harmful to human body.

Phenolic resin foam is used in various industrial applications such as building materials for various building interior and exterior materials and industrial insulation materials, because it has flame retardancy, heat resistance, low smoke resistance, dimensional stability, processability, and high insulation compared to styrofoam or urethane foam foam, which is a conventional insulation material. .

Conventional phenolic resin foam is prepared by foaming the composition by adding a foaming agent, a foaming agent, an acid hardener and a flame retardant to a predetermined proportion of phenol resin.

 As the blowing agent, a relatively high boiling point CFC or HCFC halogenated hydrocarbon-based blowing agent such as 1,1,2-trichloro-1,2,2-trifluoro ethane or dichlorodifuluro methane was used. There is a serious environmental problem that destroys the ozone layer, and its use is increasingly regulated. 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane, 1,1,1,2,2- of HCs or HFCs with almost zero global warming destruction coefficient and almost no destruction of ozone layer Pentafluoroethane and the like have been attracting attention, but since they have a low boiling point, the pressure at the time of foaming increases, so that the bubble wall of the foam foam is broken or the bubble diameter is increased, which lowers the thermal insulation effect, and when the thermal conductivity of the foaming agent itself is high. There is a problem that it is difficult to obtain a phenolic resin foam having a good thermal insulation performance on the door.

Flame retardants such as halogen-based, phosphorus-based and antimony trioxide are added alone or in combination to impart flame retardancy to foamed foams. It is known to occur. For this reason, the use of halogen-based blowing agents, flame-retardants such as phosphorus and antimony trioxide are gradually strengthened, and development efforts to use alternative materials are spreading. That is, since the substances added to give the foam a function causes a variety of problems, alternative materials have been tried to solve the problem through research or various experiments, in particular in the foam without the addition of a flame retardant Studies that impart flame retardancy need to be conducted.

Japanese Patent Application Laid-Open No. 63-32086 proposes a technique of foaming by using a combination of a phenol resin, an aromatic polyisocyanate and an aliphatic polyisocyanate. Although phenolic resin foam was used to impart flame retardancy and urethane foam to increase mechanical strength and productivity, it did not solve the difference in reaction temperature, curing temperature, foaming speed, etc. of the two compositions. Failed to provide foaming technology with satisfactory physical properties such as mechanical strength.

Japanese Patent Laid-Open Publication No. 53-13669 and Japanese Patent Laid-Open Publication No. 63-20460 minimize the amount of water in the resol-type phenolic resin or foam using high molecular weight phenolic resins to improve the strength of the bubble walls during foaming and independent foaming. Although a technique for obtaining a foam has been proposed, there is a disadvantage in that it is difficult to handle a high viscosity phenol resin and it is expensive in terms of economy because of the low degree of foaming at the time of foaming.

In Japanese Unexamined Patent Application Publication No. 3-106947, liquefied carbon dioxide is used as a hydrocarbon blowing agent known to have almost no global ozone depletion coefficient in place of the blowing agents of halogens or derivatives thereof. In addition, Japanese Patent Application Laid-Open No. 4-239040 proposes to use carbon dioxide gas generated by decomposing barium carbonate as a blowing agent, and Japanese Patent Application Laid-open No. 3-169621 uses CFC-113, liquefied carbonic acid gas, and carbonate. However, since foams obtained by blowing agents of such halogen hydrocarbons have a low independent foaming rate and a large cell diameter, it is difficult to obtain good thermal insulation performance and a problem arises due to the regulation of usage.

In Japanese Patent Laid-Open No. 4-503829, a phenol foam having good thermal insulation can be obtained by adding perfluorocarbon to a pentane hydrocarbon blowing agent. However, after time passes, fine pores are formed in the base wall of the foam, and the thermal conductivity decreases as the blowing agent is gradually replaced with air through the fine pores. Perfluorocarbons used as blowing agents are also very expensive, which leads to a high manufacturing cost.

Japanese Patent Laid-Open No. 3-179401 uses very strong acids, particularly inorganic acids such as phosphoric acid, hydrochloric acid, and sulfuric acid, and organic acids such as phenol sulfonic acid and benzenesulphonic acid as essential components when the phenol resin is foamed. Such strong acid remains in the foam and has a problem of strong corrosiveness when used in building and industrial insulation or materials, and has a disadvantage in that the application field is limited.

As described above, in the production of foamed foam of phenolic resin, environmental problems occur in the conventional method, and the foaming method using CFCs, HCFCs, HFCs, etc., which are used restriction substances, and the curing method by adding strong acid when the foaming agent is cured. Various problems such as the maintenance of the mechanical strength of the foam foam are appearing, and the necessity of research on the production of foam foam of phenol resin which can improve this is highlighted.

Thus, the inventors of the present invention in Korea Patent Registration No. 613887 uses water generated by mixing a resol type phenolic resin, foaming agent, nonionic surfactant, weakly acidic curing agent and isocyanate compound with formaldehyde removed from phenolic molecules in aqueous ammonia solution. Patents have been applied for a method for producing a flame retardant foam without the use of carbon dioxide as a blowing agent without the use of a separate blowing agent and flame retardant. However, the study of the manufacturing technology of the foam foam that does not use the isocyanate compound was caused by causing a problem that toxic gas is generated when the isocyanate compound used for the blowing agent is burned. In addition, in the present invention, a combination of foaming additives as an improvement of the manufacturing technology of the foamed foam, which is advantageously applied to the production process, has been carried out a technical research for producing a foaming composition having excellent stability and fear of deterioration of foaming rate or physical properties.

The present inventors have tried to solve the problem according to the foam foam production of the conventional phenolic resin as described above. As a result, a solution prepared by mixing a resol-type phenolic resin, a nonionic surfactant, and a weakly acidic curing agent, and a solution prepared by separately mixing a polyol foam stabilizer, a nonionic surfactant, a hydrocarbon foaming agent, and an auxiliary foaming agent of an alkali metal carbonate. To prepare a mixture of the respective solutions, the foaming process is carried out at room temperature without the use of additional heat by the heat generated during the mixing, and rapid carbonization with water generated in the resol-type phenol resin of the foam foam The formation of the layer suppresses the spread of the flame and the generation of toxic gases, and it has been found that the state of hardening at a high temperature is maintained, thereby completing the present invention.

Accordingly, an object of the present invention is to provide a method for producing a phenol resin foam in an environmentally friendly manner without the use of a separate flame retardant using two kinds of solutions containing a certain component in a certain ratio.

The present invention is a step of preparing a solution by mixing the resol-type phenolic resin 100 parts by weight, 0.1 to 5 parts by weight of the nonionic surfactant and 5 to 50 parts by weight of the weakly acidic curing agent;

Based on 100 parts by weight of the resol type phenol resin,

Preparing a solution by mixing 40 to 70 parts by weight of a polyol foam stabilizer, 0.1 to 5 parts by weight of a nonionic surfactant, 10 to 50 parts by weight of a hydrocarbon blowing agent, and 10 to 30 parts by weight of an auxiliary foaming agent of an alkali metal carbonate; And

In the method for producing a phenol resin foam comprising a three-stage solution and a two-stage solution by mixing and stirring, performing the foaming for 5 to 10 minutes by heat in the temperature range of 80 ~ 110 ℃ generated during mixing It has its features.

Hereinafter, the present invention will be described in detail.

According to the present invention, the foaming composition added to the resol-type phenol resin is prepared into two foaming compositions, respectively, and then mixed and foamed to improve foaming power and flame retardancy without using a separate flame retardant and heat source, and to extend the foaming time uniformly. It relates to a method for producing a phenolic resin foam having a foam cell.

Korean Patent Registration No. 613887, invented by the present applicant, has excellent flame retardancy by mixing a foaming agent, a nonionic surfactant, an acid curing agent, and an isocyanate compound with a resol type phenol resin in which a residual formaldehyde in the phenol resin is removed with an aqueous ammonia solution. It is the same in that the present invention and the flame-retardant foam is prepared by manufacturing a foam without adding a flame retardant to the phenolic resin having a phenolic resin, but the foamed additives are foamed in order to favor the application to the production process according to commercialization It is an invention that is completely different in technology with a manufacturing technology that separates the composition into a solution and then foams it.

In addition, there is a variety of techniques for performing foaming using a conventional blowing agent, the present invention has a feature in the technical configuration to perform the foaming to prepare a solution containing a blowing agent and a solution containing a phenolic resin differently.

Specifically, a solution containing a phenolic resin is added with a specific surfactant and a hardener, and the surfactant surrounds the surface of the resin, thereby rapidly reducing the rate of curing and foaming, thereby providing a uniform cell size. It will form a foam having. In the case of using the foaming agent according to the conventional method, the foaming is completely completed in about 2 to 3 minutes and in the case of urethane foam in about 1 to 2 minutes, but the present invention can maintain a foaming time as long as about 5 to 10 minutes. The solution containing the blowing agent contains a foam stabilizer, a blowing agent, a co-foaming agent and a surfactant at the same time, the surfactant is used to induce the initial cell formation is different from that used in the phenol resin. In addition, the alkali metal carbonate used as the auxiliary foaming agent generates carbon dioxide upon foaming, thereby improving foaming efficiency and at the same time, contributing to improving the flame retardancy of the foamed foam having excellent thermal stability. The hydrocarbon-based blowing agent used in the present invention, the mechanical properties of the foam foam prepared compared to the conventional halogen-based blowing agent is lowered, but when the solution configuration of the present invention forms a cell of uniform size, this problem is improved.

That is, the components used are known, but there is a characteristic in the technical configuration in that they are specifically optimized to form a more effective foam by limiting their combination and usage.

Referring to the method for producing a resol-type phenolic resin foam according to the present invention in detail.

A solution is prepared by mixing a resol type phenolic resin, a nonionic surfactant and a weakly acidic curing agent.

The nonionic surfactant may be selected from silicone-based and glycerin, and specifically, the silicone-based surfactant may be B-8469, B-8462, or B-8404 (Goldschmidt). It is recommended to use -8404 (Goldschmidt). The surfactant is used in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the resol-type phenolic resin. If the amount is less than 0.1 part by weight, the amount is too small, so that the effect is difficult to be expressed. There exists a problem that foaming performance exists and exists.

The weakly acidic curing agent may have a pH 2 to 5 range, and specifically, paratoluene sulfonic acid may be used. Such a weakly acidic curing agent is used in an amount of 5 to 50 parts by weight based on 100 parts by weight of the resol-type phenolic resin. When the amount is less than 5 parts by weight, curing of the foam is slow, and when it exceeds 50 parts by weight, the foaming temperature is too high. There is a problem that the speed is too fast to maintain a uniform cell of the foam.

Separately, a solution is prepared by mixing 40 to 70 parts by weight of the polyol foam stabilizer, 0.1 to 5 parts by weight of the nonionic surfactant, 10 to 50 parts by weight of the hydrocarbon blowing agent and 10 to 30 parts by weight of the auxiliary foaming agent of the alkali metal carbonate.

The polyol foam stabilizer is generally used in the art, but is not particularly limited, but MX-8651 (Gangnam Chemical) is preferably used.

The polyol foam stabilizer is used 40 to 70 parts by weight with respect to 100 parts by weight of the resol-type phenolic resin, when the amount is less than 40 parts by weight bubble adjustment is not made, there is a problem in the cell formation, exceeding 70 parts by weight In this case, there is a problem of lowering the flame retardant effect of the foam and relatively lowering the activity of other components.

The nonionic surfactant may be the same as the above-described components. When the nonionic surfactant is used in an amount of 0.1 to 5 parts by weight based on 100 parts by weight of the resol type phenolic resin, when the amount is less than 0.1 parts by weight, it is difficult to form an initial cell, and when it exceeds 5 parts by weight, the foaming performance is lowered. There is a problem.

The hydrocarbon-based blowing agent is generally used in the art, and in particular, hydrocarbon-based cyclopentane having 1 to 5 carbon atoms. When the foaming agent is used in an amount of 10 to 50 parts by weight based on 100 parts by weight, it is difficult to form a uniform and dense cell because foaming does not occur properly due to excessive foaming.

The auxiliary foaming agent of the alkali metal carbonate may be selected from sodium bicarbonate, potassium bicarbonate and sodium carbonate as a component used to improve the foaming power and the flame retardancy of the foam. The auxiliary foaming agent is used in 10 to 30 parts by weight based on 100 parts by weight of the resol-type phenolic resin, there is a problem that the foaming performance is lowered when out of the above range.

The two solutions prepared above were put in a mold and mixed to prepare a phenol resin foam. When the mixture generates a heat of reaction at a temperature of 80 to 110 ° C., foaming is performed by the generated heat of reaction without using a separate heat source. At this time, the foaming time is preferably in the range of 5 to 10 minutes, preferably about 7 minutes. This delays the foaming time for a long time compared with the case of using a conventional blowing agent, if the foam is formed with a predetermined time as described above, the size of the cell is uniform and dense, it is excellent in physical properties. All the reaction of the present invention is stirred at a high speed of 1500 to 3000 rpm each step is preferably 1500 rpm or more.

The appearance state of the phenolic resin foam prepared in the present invention is dark yellow, each cell has a closed cell (closed cell) state. The density of the foam is preferably 0.038 g / cm 3 or less, and the thermal conductivity is 0.020 kPa to 0.025 Kcal / m · h · ° C., which may be called a foam having physical properties corresponding to the density and thermal conductivity suitable as a heat insulating material.

In addition, the size of each cell is usually 50.0 ~ 160.0 ㎛ suitable and the cell of the phenol resin foam foam prepared in the present invention belongs to the size range of 54.4 ~ 100.0 ㎛.

Such a present invention will be described in more detail based on the following examples, but the present invention is not equivalent thereto.

 Example 1

In order to prepare a phenol resin foam composition, the following two solutions were prepared by quantification.

Composition A): 150 g of a phenol resin, 3 g of a surfactant (manufactured by Goldschmidt, manufactured by B-8404), and 20 g of paratoluene sulfonic acid as a weakly acid hardener were added thereto, and prepared at room temperature of 25 ° C.

Composition B): 100 g of a foam stabilizer (MX-8651, Gangnam Chemical), 10 g of a surfactant glycerin, 25 g of cyclopentane, a blowing agent, and 25 g of sodium bicarbonate, a co-foaming agent, were added and stirred at 2500 rpm for about 10 minutes. .

 The composition solution A) and the composition solution B) were mixed in the mold and stirred, and foamed at a temperature in the range of 110 ° C. formed for the mixing for about 7 minutes to prepare a foam.

Example 2

In the same manner as in Example 1, but was prepared using 180g of the phenol resin of the foaming composition A).

Example 3

It was carried out in the same manner as in Example 1, but was prepared using 200 g of the phenol resin of the foaming composition A).

The components and contents used in preparing the phenol resin foams performed in Examples 1 to 3 are summarized in the following table.

division Ingredient (g) Example 1 Example 2 Example 3 Phenolic Resin ¹⁾ 150 180 200 Surfactants B-8404 ²⁾ 3 3 3 Glycerin 10 10 10 Foam stabilizer ³⁾ 100 100 100 Foaming agent ^{4 )} 25 25 25 Curing agent ^{5 )} 20 20 20 Secondary foaming agent ^{6 )} 25 25 25 1) Resol type phenolic resin 2) Goldschmit, main component silicone 3) Gangnam Hwaseong, MX-8651, main component polyol, 4) cyclopentane 5) paratoluenesulphonic acid 6) sodium bicarbonate

Experimental Example 1: Thermal Characteristics (Combustion Temperature, Volatility)

The phenol resin foams prepared in Examples 1 to 3, and conventionally commercialized styrofoam and urethane foams were calcined at a temperature in the range of 100 to 700 ° C. for one hour, respectively, and the results of analyzing the volatilities thereof are shown in Table 2 below. Shown in

Temperature Type of foam (wt%) Example 1 Example 2 Example 3 Styrofoam Urethane Foam 100 14.6 14.1 13.7 1.8 1.4 150 23.7 23.3 22.8 2.6 7.9 200 25.9 24.6 23.5 7.9 16.4 250 32.8 31.9 31.4 55.2 29.6 300 35.5 34.7 29.2 97.4 71.8 400 57.6 50.8 48.7 100 96.6 500 70.4 68.5 67.3 - 100 600 78.3 76.8 74.9 - - 700 82.6 80.7 78.3 - -

As shown in Table 2, the styrofoam and urethane foam was 100% volatilized at 400 ℃ and 500 ℃, respectively, the phenolic resin foam foam prepared in Examples 1 to 3 of the present invention is about 80% of the volatilization at 700 ℃ Showed.

The volatilization tendency according to the temperature change from 100 to 700 ° C. shows that styrofoam rapidly increases volatilization at 250 ° C., while urethane foam rapidly increases volatilization at 300 ° C., while the phenols of Examples 1 to 3 As the temperature of the resin foam increased to 100 to 700 ° C, the volatilization gradually increased. This can be confirmed that the phenolic resin foam prepared in the present invention has a high heat stability and excellent heat resistance.

The amount of the resol type phenol resin in the phenol resin foam is 30 to 40% by weight in total, even though all of the highly volatile additives in the foam are volatilized, the heat resistance of the manufactured phenol foam is very excellent.

On the other hand, conventional foamed styrofoam is a shrinkage of the foam occurs at 100 ℃ or less, polyurethane foam shrinkage of the foam at 140 ~ 200 ℃ occurs. When the foamed foam shrinks and hardens, the foam loses its thermal insulation properties, and thus the effect is lowered when used as an insulating material. However, since the curing of the phenolic resin foam of the present invention starts at a higher temperature, the highest temperature compared with other foams in the related art. It can be seen that the form is not cured by heat until.

Therefore, the phenolic resin foam of the present invention has high heat resistance and has excellent properties as a heat insulating material because of its high heat resistance at high temperatures.

As shown in Table 2, as a result of analyzing the heat resistance and thermal properties of the resol-type phenolic resin foam prepared in the present invention, both show the physical properties satisfying suitable conditions.

Experimental Example 2 Measurement of Physical Properties

The thermal conductivity of the phenolic resin foams prepared in Examples 1 to 3 and foamed foams such as styrofoam, rock wool, glass wool, etc., which were conventionally commercialized, were measured and shown in Table 3 below.

division Example Styrofoam Urethane Foam Rock wool Glass wool One 2 3 Thermal Conductivity (Kcal / m · h · ℃) 0.026 0.023 0.021 0.032 0.020 0.023 0.033

In general, thermal insulation, which is one of thermal characteristics, may be determined by thermal conductivity (K-factor) according to the density of foam foam. The lower the thermal conductivity, the better the thermal insulation.

As shown in Table 3, the thermal conductivity of the phenol resin foams prepared in Examples 1 to 3 according to the present invention is 0.021 ~ 0.026 Kcal / mh ℃ styrofoam (0.032 Kcal / m · h · ℃), rock wool (Rock wool) (0.023 Kcal / m · h · ° C) and glass wool (0.033 Kcal / m · h · ° C), showing similar or low thermal conductivity. In addition, the urethane foam (0.015 ~ 0.020 Kcal / m · h · ℃) appears to have a lower thermal conductivity than the phenol resin foam foam, but shows a very unstable thermal conductivity distribution against temperature changes. On the other hand, the thermal conductivity of the phenol resin foam is stable, and the thermal conductivity is almost constant.

Therefore, the phenolic resin foam having high heat resistance and low thermal conductivity has excellent properties as a heat insulating material or a heat insulating material due to its excellent heat insulating properties.

As described above, the present invention performs a foaming process using two composition liquids having a specific component and composition to prepare a foamed foam excellent in physical properties such as heat insulation, heat resistance, heat insulation without the use of a separate flame retardant foaming existing heat insulating material In addition to the foam replacement effect, various applications to industrial and building materials using high heat resistant phenolic resins are expected.

Claims (6)

1 step of preparing a solution by mixing 0.1 to 5 parts by weight of a nonionic surfactant and 5 to 50 parts by weight of a weakly acidic curing agent to 100 parts by weight of a resol-type phenol resin; Based on 100 parts by weight of the resol type phenol resin, Preparing a solution by mixing 40 to 70 parts by weight of a polyol foam stabilizer, 0.1 to 5 parts by weight of a nonionic surfactant, 10 to 50 parts by weight of a hydrocarbon blowing agent, and 10 to 30 parts by weight of an auxiliary foaming agent of an alkali metal carbonate; And Mixing and stirring the one-step solution and the two-step solution, three steps of performing foaming for 5 to 10 minutes by heat in the temperature range of 80 ~ 110 ℃ generated during mixing Method for producing a phenolic resin foam, characterized in that made. The method of claim 1, wherein the nonionic surfactant is selected from silicone-based surfactants and glycerin. The method of claim 1, wherein the weakly acidic curing agent is paratoluenesulphonic acid. The method of claim 1, wherein the hydrocarbon-based blowing agent is cyclopentane. The method of claim 1, wherein the auxiliary foaming agent of the alkali metal carbonate is selected from sodium bicarbonate, potassium bicarbonate and sodium carbonate. The foamed foam according to claim 1, wherein the foamed foam has a density of 0.038 g / cm 3 or less, a thermal conductivity of 0.020 kPa to 0.025 Kcal / m · h ° C., and a foamed foam cell of 54.4 to 100.0 μm. Method for producing a phenol resin foam.