Flame retardant composition for impregnation and manufacturing method therefor

Abstract

The present invention relates to a flame retardant composition for impregnation and and a method for manufacturing the flame retardant composition for impregnation, the flame retardant composition being capable of improving flame retardancy by impregnating a polymer foam such as polyurethane foam or silicone foam, building interior and exterior materials, fabrics, plastics, wood boards, glass fibers, panels, paper, and the like with an inorganic phosphate binder formed by reaction of an aluminum-containing compound and phosphoric acid.

Description

Flame retardant composition for impregnation and method for producing the same

[0001] The present invention relates to a flame retardant composition for impregnation that can improve flame retardancy by impregnating an inorganic phosphoric acid binder formed by the reaction of an aluminum-containing compound and phosphoric acid into polymer foams including polyurethane foam and silicone foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, etc., and a method for producing the flame retardant composition for impregnation.

[0002] Polymer foams including polyurethane foam and silicone foam, interior and exterior building materials, fabrics, plastics, wood panels, fiberglass, panels, and paper must meet flame retardant standards to ensure fire safety.

[0003] Methods for imparting flame retardancy include a method of polymerizing by including a flame retardant monomer, a method of mixing a flame retardant or flame retardant aid into the manufactured resin, and a method of impregnating, coating, or painting a flame retardant. The flame retardants include halogen-based flame retardants and non-halogen-based flame retardants such as phosphorus-based, nitrogen-based, and hydroxide-based, and the flame retardant aids include antimony-based compounds, silicone-based compounds, and zinc-based compounds.

[0004] The above halogenated flame retardant has a higher flame retardant efficiency than the non-halogenated flame retardant and can maintain the mechanical properties of the resin, so a method of imparting flame retardancy and flame resistance to materials made of organic substances by applying a flame-resistant composition containing a halide has been applied to various products (U.S. Patent No. 4,532,287). However, when a halogenated flame retardant is added to process a resin, a large amount of environmental pollutants are generated during the cycle of processing, use, and disposal, which has a problem of having a negative impact on the work environment and the human body.

[0005] To avoid the above problems, there is a method of using a non-halogen flame retardant or, more recently, a metal hydroxide compound known to have an excellent flame retardant effect as a representative inorganic flame retardant. However, non-halogen flame retardants and metal hydroxide compounds have a lower flame retardant efficiency than halogen flame retardants, so they have the disadvantage of requiring a significant increase in the amount added.

[0006] In this regard, Korean Patent No. 10-0863282 discloses a method for forming a new crystalline product having the properties of a metal hydroxide and phosphoric acid by reacting the hydroxyl groups of aluminum hydroxide, magnesium hydroxide, and calcium hydroxide with phosphoric acid in a high-temperature aqueous solution to form a phosphate of a metal hydroxide, but this method has the disadvantage that it produces a crystalline product and the flame retardant cannot be used by immersion, coating, or painting.

[0007] Accordingly, there is a need for the development of flame retardants that can effectively impart flame retardancy to polymer foams including polyurethane foam and silicone foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, etc. while exhibiting flame retardancy efficiency superior to that of halogen-based flame retardants.

[0008] The present invention aims to provide a flame retardant composition for impregnation that can improve flame retardancy by impregnating an inorganic phosphoric acid binder formed by the reaction of an aluminum-containing compound and phosphoric acid into polymer foams including polyurethane foam and silicone foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, etc.

[0009] In addition, the present invention provides a method for producing the flame retardant composition for impregnation by producing a secondary reactant formed by mixing colloidal silica with a primary reactant formed through first and second reactions of an aluminum-containing compound and phosphoric acid.

[0010] To solve the above problem,

[0011] In one embodiment, the present invention provides a flame retardant composition for impregnation comprising a first reactant obtained by reacting a phosphorus compound, an aluminum-containing compound, and water; and a second reactant obtained by adding colloidal silica to the first reactant.

[0012] The flame retardant composition for impregnation may include 40 to 55 wt% of the phosphorus compound; 8 to 20 wt% of the aluminum-containing compound; 10 to 20 wt% of the water; and 20 to 25 wt% of the colloidal silica.

[0013] The reaction molar ratio of the aluminum-containing compound and the phosphorus compound may be 1:2 to 5.

[0014] The above-mentioned phosphorus compound may include at least one selected from the group consisting of phosphoric acid (or orthophosphoric aicd), pyrophosphoric aicd, tripolyphosphoric aicd, tetrapolyphosphoric acid, polyphosphoric acid, and trimetaphosphoric acid, phosphoric anhydride, trimethyl phosphate, hexamethylphosphoric triamid, and combinations thereof.

[0015] The above aluminum-containing compound may include at least one selected from the group consisting of aluminum hydroxide, aluminum oxide (alumina), aluminum phosphate, and combinations thereof.

[0016] The above flame retardant composition for impregnation is liquid, and the colloidal silica may improve storage stability.

[0017] The pH of the above impregnating flame retardant composition may be pH 2.5 to 5.

[0018] The above flame retardant composition for impregnation may be used to impregnate one or more selected from the group consisting of polymer foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, and combinations thereof.

[0019] In addition, the present invention provides a method for producing a flame retardant composition for impregnation, comprising, in one embodiment, a step of mixing and reacting a phosphorus compound, an aluminum-containing compound, and water to produce a transparent liquid first reactant; and a step of mixing colloidal silica with the first reactant to produce a second reactant.

[0020] The above first reactant may be a mixture of a phosphorus compound, an aluminum-containing compound, and water, stirred at 40 to 60°C to cause a first reaction, and then stirred at 80 to 100°C to cause a second reaction until the mixture becomes transparent.

[0021] The flame retardant composition for impregnation according to the present invention is an inorganic phosphoric acid binder formed by the reaction of an aluminum-containing compound and a phosphorus compound, and is a liquid flame retardant that can improve the flame retardancy of a base material during impregnation or coating by having advantageous physical properties of aluminum metal and phosphoric acid.

[0022] In particular, the flame retardant composition for impregnation has high adhesiveness and heat resistance, so that it can prevent damage to the base material due to thermal deformation even in a high-temperature environment or a situation where a sudden thermal shock occurs, minimize the generation of toxic gases due to fire in the event of a fire, and prevent detachment from the base material due to flexibility at high temperatures even when a difference in thermal expansion coefficient occurs with the base material.

[0023] In addition, it can maintain excellent durability and contamination resistance regardless of the base material used, including metals and non-ferrous metals, and has the characteristic of not using organic solvents so that people can lead a healthy life.

[0024] Figure 1 shows a UL 94 V test image (a) and a specimen (b) before (upper specimen) / after (lower specimen) testing according to an embodiment of the present invention.

[0025] The present invention can have various modifications and various embodiments, and specific embodiments are illustrated in the drawings and specifically described in the detailed description.

[0026] However, this is not intended to limit the present invention to a specific embodiment, but should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

[0027] In the present invention, it should be understood that terms such as “include” or “have” are intended to specify the presence of a feature, number, step, operation, component, part or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts or combinations thereof.

[0028] Hereinafter, the present invention will be described in detail.

[0029] The present invention provides a flame retardant composition for impregnation that can improve flame retardancy by impregnating an inorganic phosphoric acid binder formed by the reaction of an aluminum-containing compound and phosphoric acid into polymer foams including polyurethane foam and silicone foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, etc.

[0030] Specifically, the present invention provides a flame retardant composition for impregnation comprising a first reactant in which a phosphorus compound, an aluminum-containing compound, and water are reacted; and a second reactant in which colloidal silica is added to the first reactant.

[0031] The flame retardant composition for impregnation according to the present invention is an inorganic phosphoric acid binder formed by the reaction of an aluminum-containing compound and a phosphorus compound, and is a liquid flame retardant that can improve the flame retardancy of a base material during impregnation or coating by having advantageous physical properties of aluminum metal and phosphoric acid.

[0032] In particular, the flame retardant composition for impregnation has high adhesiveness and heat resistance, so that it can prevent damage to the base material due to thermal deformation even in a high-temperature environment or a situation where a sudden thermal shock occurs, minimize the generation of toxic gases due to fire in the event of a fire, and prevent detachment from the base material due to flexibility at high temperatures even when a difference in thermal expansion coefficient occurs with the base material.

[0033] In addition, it can maintain excellent durability and contamination resistance regardless of the base material used, including metals and non-ferrous metals, and has the characteristic of not using organic solvents so that people can lead a healthy life.

[0034] The flame retardant composition for impregnation may include 40 to 55 wt% of the phosphorus compound; 8 to 20 wt% of the aluminum-containing compound; 10 to 20 wt% of the water; and 20 to 25 wt% of the colloidal silica.

[0035] Here, if the aluminum-containing compound is added in an amount of less than 8 wt%, there is a problem that the brittleness of the surface of the flame retardant for impregnation is reduced, and if it exceeds 20 wt%, there is a problem that a transparent liquid cannot be obtained during the acid reaction process. In this case, the reduced brittleness means that the thermal expansion coefficient of the base material and the flame retardant composition for impregnation are different, and thus the degree of expansion of the base material and the flame retardant composition is different, resulting in a problem that the flame retardant composition is peeled off from the surface of the base material.

[0036] The above aluminum-containing compound may include at least one selected from the group consisting of aluminum hydroxide, aluminum oxide (alumina), aluminum phosphate, and combinations thereof. In particular, the aluminum phosphate contains phosphoric acid in addition to aluminum, thereby further improving flame retardancy.

[0037] The 'phosphorus (P)' material contained in the above phosphorus compound is applied to combustible materials to delay combustion or prevent the expansion of combustion, and the phosphorus-based flame retardant composition containing such phosphorus (P) is known to be utilized as a material of an effective flame retardant composition by blocking the hydrocarbons forming the skeleton of the combustible product from participating in the combustion reaction any further by forming a carbon film (char) by dehydration of polymetaphosphoric acid, which is one principle of the flame retardant mechanism. Accordingly, the flame retardant composition for impregnation of the present invention can improve flame retardancy by using a phosphorus-based compound containing phosphorus (P).

[0038] The above-mentioned phosphorus compound may include at least one selected from the group consisting of phosphoric acid (or orthophosphoric aicd), pyrophosphoric aicd, tripolyphosphoric aicd, tetrapolyphosphoric acid, polyphosphoric acid, and trimetaphosphoric acid, phosphoric anhydride, trimethyl phosphate, hexamethylphosphoric triamid, and combinations thereof.

[0039] The water may contain 10 to 20 wt% of water, so that the phosphorus compound can be completely dissolved in the water. At this time, the water may include purified water or distilled water.

[0040] The above colloidal silica is added to prevent the base material from being excessively corroded by the phosphoric acid of the phosphorus compound, and can play a role in lowering the acidity of the phosphoric acid.

[0041] The pH of the above impregnating flame retardant composition may be pH 2.5 to 5. The primary reactant formed by reacting the phosphorus compound, the aluminum-containing compound, and the water may have a pH of 1 to 2 due to the phosphoric acid of the phosphorus compound, but the pH may be adjusted to a range of 2.5 to 5 by the colloidal silica. For example, the pH may be 2.5 to 4, 2.5 to 3.5, 3 to 4, or 4 to 5.

[0042] If the colloidal silica is added in an amount less than 20 wt%, the impregnating flame retardant composition may excessively corrode the base material, thereby causing a problem of lowering the physical properties of the base material. If the colloidal silica is added in an amount exceeding 25 wt%, the surface area of ​​the base material in contact with the impregnating flame retardant composition may be reduced, causing a problem of reduced bonding strength between the impregnating flame retardant composition and the base material.

[0043] The colloidal silica may have a pH of 8 to 10 and may include, for example, one selected from the group consisting of Snowtex 40, SS Sol 30A, and combinations thereof.

[0044] The amount of material in each of the first reactant and the second reactant of the impregnating flame retardant composition may include 45 to 65 wt% of the phosphorus compound in the first reactant; 15 to 25 wt% of the aluminum-containing compound; and 13 to 23 wt% of the water in the second reactant, and 70 to 85 wt% of the first reactant and 15 to 30 wt% of the colloidal silica in the second reactant.

[0045] The reaction molar ratio of the aluminum-containing compound and the phosphorus-based compound may be 1:2 to 5. The impregnating flame retardant composition may have a stable viscosity at the reaction molar ratio within the above range and may improve heat resistance. For example, the impregnating flame retardant composition may have a reaction molar ratio of the aluminum-containing compound and the phosphorus-based compound within an equivalent range of 1:2 to 5, 1:2 to 4, 1:2 to 3.5, 1:3 to 5, or 1:3 to 4.

[0046] The above flame retardant composition for impregnation is in a liquid state, and the colloidal silica may improve storage stability. To prepare the above flame retardant composition for impregnation in a liquid state, the colloidal silica may be added to increase the solid content and control the viscosity, thereby improving storage stability even in a liquid state and also playing a role in improving heat resistance.

[0047] The above flame retardant composition for impregnation may be used to impregnate one or more selected from the group consisting of polymer foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, and combinations thereof. In particular, the above flame retardant composition for impregnation may be used to manufacture a flame retardant contact pressure pad that is positioned between cells of a secondary battery to prevent thermal runaway by impregnating a polymer foam including polyurethane foam or silicone foam.

[0048] In addition, the present invention provides a method for producing the flame retardant composition for impregnation by producing a secondary reactant formed by mixing colloidal silica with a primary reactant formed through first and second reactions of an aluminum-containing compound and phosphoric acid.

[0049] Specifically, the present invention provides a method for producing a flame retardant composition for impregnation, comprising the steps of: preparing a transparent liquid first reactant by mixing and reacting a phosphorus compound, an aluminum-containing compound, and water; and preparing a second reactant by mixing colloidal silica with the first reactant.

[0050] The method for preparing the above flame retardant composition for impregnation is as follows: first, a phosphoric acid aqueous solution is prepared by mixing the phosphorus compound and water, and then the phosphoric acid aqueous solution is reacted with the aluminum-containing compound to form a phosphoric acid binder (primary reactant). Finally, the phosphoric acid binder and the colloidal silica are mixed to prepare a flame retardant composition for impregnation (secondary reactant).

[0051] The above first reactant may be a mixture of a phosphorus compound, an aluminum-containing compound, and water, stirred at 40 to 60°C to cause a first reaction, and then stirred at 80 to 100°C to cause a second reaction until the mixture becomes transparent.

[0052] After the first reaction, the second reaction may be performed for 2 to 3 hours until the material becomes transparent, and the phase transition reaction may be performed through the first reaction and the second reaction to improve water resistance.

[0053] By adjusting the viscosity by mixing colloidal silica in the step of manufacturing the above secondary reactant, an impregnation flame retardant composition with improved storage stability and heat resistance even in a liquid state can be manufactured.

[0054] Hereinafter, the present invention will be described in more detail through examples according to the present invention, but the scope of the present invention is not limited by the examples presented below.

[0055] [Example]

[0056] Example 1: Preparation of a flame retardant composition for impregnation having a molar ratio of aluminum hydroxide and phosphoric acid of 1:2.3

[0057] To prepare a flame retardant composition for impregnation, 103.09 kg of phosphoric acid was added to a jacket tank, and 36.01 kg of water was added while stirring. Thereafter, 30.90 kg of aluminum hydroxide (LS-100) was slowly added at room temperature, and the temperature of the reaction section of the jacket tank was raised to 40 to 60°C and stirred to initiate the first reaction. Then, the temperature of the reaction section was raised to 80 to 100°C and stirred until a transparent liquid was formed through the second reaction, thereby forming the first reactant.

[0058] After the jacket tank was cooled to room temperature, 40.15 kg of colloidal silica (SNOWTEX-40) was mixed with 170.0 kg of the first reactant to prepare a liquid flame retardant composition for impregnation as a second reactant.

[0059] Example 2: Preparation of a flame retardant composition for impregnation having a molar ratio of aluminum hydroxide and phosphoric acid of 1:2.7

[0060] A liquid flame retardant composition for impregnation was prepared in the same manner as in Example 1, except that the molar ratio of aluminum hydroxide and phosphoric acid was 1:2.7, using 121.02 kg of phosphoric acid and 30.90 kg of aluminum hydroxide.

[0061] Comparative Example 1: Preparation of flame retardant composition for impregnation not containing colloidal silica

[0062] In order to prepare a flame retardant composition for impregnation that does not contain colloidal silica, 103.09 kg of phosphoric acid was added to a jacket tank, and 36.01 kg of water was added while stirring. Thereafter, 30.90 kg of aluminum hydroxide (LS-100) was slowly added at room temperature, and the temperature of the reaction part of the jacket tank was raised to 40 to 60°C and stirred to initiate a first reaction. Then, the temperature of the reaction part was raised to 80 to 100°C and stirred until a transparent liquid was formed by a second reaction to form a first reactant. After the temperature of the jacket tank was cooled to room temperature, a liquid flame retardant composition for impregnation was prepared.

[0063] Comparative Example 2: Preparation of a flame retardant composition for impregnation having a molar ratio of aluminum hydroxide and phosphoric acid of 1:1

[0064] A liquid flame retardant composition for impregnation was prepared in the same manner as in Example 1, except that the molar ratio of aluminum hydroxide and phosphoric acid was 1:1, using 44.8 kg of phosphoric acid and 30.90 kg of aluminum hydroxide.

[0065] Experimental Example 1: Flame Retardancy Evaluation

[0066] In order to conduct the UL 94 V (Vertical burning test) test, the flame retardant compositions prepared in each of the examples and comparative examples were impregnated into polyurethane foam sheets measuring 13 mm × 125 mm in size and 1 mm in width, and then dried to prepare specimens of Examples 1, 2, Comparative Examples 1, and 1. The prepared specimens were installed vertically and ignited at a flame distance of 2 mm to conduct the UL 94 V test, and were evaluated according to the following evaluation methods and evaluation criteria (Table 1).

[0067] 1. After applying the flame to the specimen for 10 seconds, measure the combustion time t1 of the specimen and record the combustion pattern.

[0068] 2. After the first contact, when combustion is completed, the combustion time t2 and the glowing time t3 of the specimen after contact are measured again for 10 seconds, and the combustion pattern is recorded.

[0069] 3. Calculate the flame retardant grade by judging the combustion time and combustion pattern of t1, t2, and t3 (whether the surface ignites due to loading, whether combustion reaches the clamp, etc.)

[0070]

[0071] Figure 1 shows a specimen impregnated with the flame retardant composition of Example 1. Even after the flame retardancy test, only soot was generated by the flame and no fire or burning occurred. As a result of the flame retardancy evaluation, Examples 1 and 2 were measured as V0 grades, but Comparative Examples 1 and 2 were measured as V1 grades, indicating that the flame retardancy was inferior to that of the Examples.

[0072] Experimental Example 2: Storage Stability Evaluation

[0073] Storage stability was evaluated by observing the presence of sedimentation, layer separation, and caking phenomena after storing the flame retardant compositions prepared in the Examples and Comparative Examples at room temperature (20 to 35°C). The period during which no change occurred was observed. Storage stability was determined based on a period of at least 6 months.

[0074] Examples 1, 2, and Comparative Example 2, which contain colloidal silica, were found to remain unchanged for up to 6 months, confirming that they have storage stability for more than 6 months. On the other hand, Comparative Example 1 showed a change in liquid phase after about 1 month, confirming that they have storage stability for less than 1 month.

[0075] Therefore, it was found that colloidal silica improves the storage stability in the liquid state.

[0076] Although the embodiments of the present invention have been described with reference to the attached drawings, those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical concept or essential features thereof. Therefore, the embodiments described above should be understood to be illustrative in all respects and not restrictive.

[0077] In addition, the scope of this specification is indicated by the scope of the patent claims described below rather than the detailed description above, and all changes or modifications derived from the meaning and scope of the scope of the patent claims and their equivalent concepts should be interpreted as being included in the scope of this specification.

[0078] Meanwhile, this specification and drawings disclose preferred embodiments of this specification, and although specific terms are used, they are used in a general sense only to easily explain the technical contents of this specification and help understand the invention, and are not intended to limit the scope of this specification. It will be apparent to those skilled in the art that other modifications based on the technical idea of ​​this specification are possible in addition to the embodiments disclosed herein.

[0079] The present invention can be widely used in the field of flame retardant compositions for impregnation.

Claims

1. A primary reactant comprising a phosphorus compound, an aluminum-containing compound, and water; and An impregnating flame retardant composition comprising a secondary reactant to which colloidal silica is added to the above primary reactant.

2. In paragraph 1, The above flame retardant composition for impregnation is, 40 to 55 wt% of the above-mentioned phosphorus compound; 8 to 20 wt% of the above aluminum-containing compound; 10 to 20 wt% of the above water; and, A flame retardant composition for impregnation comprising 20 to 25 wt% of the colloidal silica.

3. In paragraph 1, A flame retardant composition for impregnation, wherein the reaction molar ratio of the aluminum-containing compound and the phosphorus compound is 1:2 to 5.

4. In paragraph 1, A flame retardant composition for impregnation, wherein the phosphorus compound comprises at least one selected from the group consisting of phosphoric acid (or orthophosphoric aicd), pyrophosphoric aicd, tripolyphosphoric aicd, tetrapolyphosphoric acid, polyphosphoric acid, trimetaphosphoric acid, phosphoric anhydride, trimethyl phosphate, hexamethylphosphoric triamid, and combinations thereof.

5. In paragraph 1, A flame retardant composition for impregnation, wherein the aluminum-containing compound comprises at least one selected from the group consisting of aluminum hydroxide, aluminum oxide (alumina), aluminum phosphate, and combinations thereof.

6. In paragraph 1, The above flame retardant composition for impregnation is in a liquid state, and the colloidal silica is an impregnating flame retardant composition that improves storage stability.

7. In paragraph 1, A flame retardant composition for impregnation, wherein the pH of the flame retardant composition for impregnation is pH 2.5 to 5.

8. In paragraph 1, The above flame retardant composition for impregnation is a flame retardant composition for impregnation that impregnates at least one selected from the group consisting of polymer foam, interior and exterior building materials, fabrics, plastics, wood panels, glass fibers, panels, paper, and combinations thereof.

9. A step of mixing and reacting a phosphorus compound, an aluminum-containing compound, and water to produce a transparent liquid first reactant; and A method for producing a flame retardant composition for impregnation, comprising a step of producing a secondary reactant by mixing colloidal silica into the primary reactant.

10. In paragraph 9, A method for producing a flame retardant composition for impregnation, wherein the first reactant is a mixture of a phosphorus compound, an aluminum-containing compound, and water, stirred at 40 to 60°C to cause a first reaction, and then stirred at 80 to 100°C to cause a second reaction until transparent.

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