Foamed polyurethane composition and polyurethane foam

Abstract

To provide an expandable polyurethane composition that can form a foam excellent in fire resistance, has excellent handleability due to difficulty to generate precipitate at the time of storage, and can suppress wearing of a spraying device used at the time of use.SOLUTION: A foaming polyurethane composition comprising a polyol compound, a polyisocyanate compound, a catalyst, a foaming agent, and a liquid flame retardant, in which the foaming polyurethane composition does not substantially contain an inorganic filler; when the polyurethane foam formed from the foaming polyurethane composition is measured under the following condition with TG-DTA at 300°C, a weight loss rate is 40% or smaller. TG-DTA measurement is carried out by measuring the position of 5 mm to 10 mm from the surface of the polyurethane foam, and the sample is measured at a temperature rise rate of 10°C / min and a measured temperature range of 40 to 1000°C for the measurement sample.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a foaming polyurethane composition and a polyurethane foam formed from the composition.

Background Art

[0002] Polyurethane foams are utilized for heat insulation and dew condensation prevention of ceilings, roofs, wall surfaces, etc. of buildings such as apartment houses, detached houses, and commercial buildings by taking advantage of their excellent heat insulation properties. Although polyurethane foams are lightweight, they are combustible because they are organic substances. To improve this, a polyurethane foam with enhanced flame retardancy, which contains a flame retardant, etc., is used. For example, in Patent Document 1, there is described a flame-retardant polyurethane foam obtained by using ammonium polyphosphate, a urea derivative, a polyol, and an isocyanate, wherein the flame-retardant polyurethane foam is obtained by using ammonium polyphosphate in the range of 5 to 150 parts by weight and a urea derivative in the range of 0.001 to 15 parts by weight with respect to 100 parts by weight of the polyol. Further, in Patent Document 2, there is described a foaming polyurethane composition obtained by reacting a polyol with an isocyanate, wherein the foaming polyurethane composition contains a foam stabilizer, a catalyst, a foaming agent, and a flame retardant, and the weight loss rate of the cured foaming polyurethane composition at 330 °C is 30% or less.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] The polyurethane compositions and foams described in Patent Documents 1 and 2 above possess a certain degree of flame retardancy. However, Patent Document 1 uses a solid flame retardant, and Patent Document 2, in all disclosed examples, uses powders such as commonly used solid flame retardants like red phosphorus or fillers (corresponding to inorganic fillers described later). Thus, when inorganic fillers, which are powders, are included in compositions for forming polyurethane foams, problems arise such as the formation of precipitates during storage, making them difficult to handle, and wear on equipment used during use. Furthermore, Patent Documents 1 and 2 do not describe or suggest any method for improving flame retardancy without using inorganic fillers. Therefore, the objective is to provide a foamable polyurethane composition that substantially does not contain inorganic fillers in powder form and is capable of forming a foam with excellent flame retardancy. [Means for solving the problem]

[0005] The inventors diligently studied to solve the above problems. As a result, they found that the above problems can be solved by a foamed polyurethane composition that contains a polyol compound, a polyisocyanate compound, a catalyst, a blowing agent, and a liquid flame retardant, and does not contain an inorganic filler, and has a weight loss rate of 40% or less at 300°C when measured by TG-DTA under certain conditions. In other words, the present invention provides the following [1] to

[11] . [1] A foamed polyurethane composition comprising a polyol compound, a polyisocyanate compound, a catalyst, a blowing agent, and a liquid flame retardant, wherein the foamed polyurethane composition substantially does not contain an inorganic filler, and the polyurethane foam formed from the foamed polyurethane composition has a weight loss rate of 40% or less at 300°C when measured by TG-DTA under the following conditions. (TG-DTA measurement conditions) A sample is cut from a polyurethane foam at a depth of 5mm to 10mm from the surface, and TG-DTA measurement is performed on this sample at a heating rate of 10°C / min and within a measurement temperature range of 40 to 1000°C. [2] The foamable polyurethane composition according to [1] above, which is a mixture of a polyol premix containing a polyol compound, a catalyst, a blowing agent, and a liquid flame retardant, and a polyisocyanate compound. [3] The foaming polyurethane composition according to [1] or [2] above, wherein the foaming agent comprises a hydrofluoroolefin. [4] The foamed polyurethane composition according to any one of [1] to [3] above, wherein the polyol compound contains a polyester polyol. [5] The foamed polyurethane composition according to any one of [1] to [4] above, wherein the polyol compound contains a polyester polyol and a polyether polyol. [6] The foamed polyurethane composition according to [4] or [5] above, wherein the polyester polyol content is more than 50% by mass on a basis of the total amount of polyol compounds. [7] The foamed polyurethane composition according to any one of [4] to [6] above, wherein the polyester polyol is a phthalic acid-based polyester polyol. [8] The foamed polyurethane composition according to any one of [1] to [7] above, wherein the catalyst contains a trimerizing catalyst. [9] A foamed polyurethane composition according to any of [1] to [8] above, wherein the isocyanate index is 150 to 700.

[10] A foamed polyurethane composition according to any of [1] to [9] above, for use in spray applications.

[11] A polyurethane foam formed from a foamable polyurethane composition comprising a polyol compound, a polyisocyanate compound, a catalyst, a blowing agent, and a liquid flame retardant, The foamed polyurethane composition substantially does not contain inorganic fillers, A polyurethane foam having a weight loss rate of 40% or less at 300°C when measured by TG-DTA under the following conditions. (TG-DTA measurement conditions) A sample is cut from a polyurethane foam at a depth of 5mm to 10mm from the surface, and TG-DTA measurement is performed on this sample at a heating rate of 10°C / min and within a measurement temperature range of 40 to 1000°C. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a foamed polyurethane composition that can form a foam with excellent flame retardancy, is easy to handle due to the low likelihood of precipitate formation during storage, and can suppress wear on spraying equipment and other devices used during use. [Modes for carrying out the invention]

[0007] [Foaming compound composition] The foamable polyurethane composition of the present invention is a foamable polyurethane composition comprising a polyol compound, a polyisocyanate compound, a catalyst, a blowing agent, and a liquid flame retardant, wherein the foamable polyurethane composition substantially does not contain inorganic fillers, and the weight loss rate at 300°C when the polyurethane foam formed from the foamable polyurethane composition is measured by TG-DTA under the following conditions is 40% or less. (TG-DTA measurement conditions) A sample is cut from a polyurethane foam at a depth of 5mm to 10mm from the surface, and TG-DTA measurement is performed on this sample at a heating rate of 10°C / min and within a measurement temperature range of 40 to 1000°C.

[0008] <Weight reduction rate> The foamable polyurethane composition of the present invention is a foamable polyurethane composition in which the weight loss rate at 300°C is 40% or less when the polyurethane foam formed from the composition is measured by TG-DTA (thermogravimetric differential thermal analysis) under the conditions described later. When the weight reduction rate exceeds 40%, the polyurethane foam formed from the foaming polyurethane composition is liable to undergo oxidative decomposition during a fire, and the flame retardancy decreases. From the viewpoint of improving the flame retardancy, the above weight reduction rate is preferably 39% or less, more preferably 38% or less. The lower the weight reduction rate, the more the oxidative decomposition is suppressed and the higher the flame retardancy, so 0% is preferable. The weight reduction rate at 300 °C is determined by the following formula (1) from the weight of the sample (polyurethane foam) before measurement and the weight of the sample at 300 °C in the TG-DTA measurement. Weight reduction rate at 300 °C (%) = 100×(weight of the sample before the test - weight of the sample at 300 °C) / weight of the sample before measurement ··· Formula (1) The weight of the sample at 300 °C in Formula (1) is the weight of the sample when reaching 300 °C in the TG-DTA measurement, when the temperature is raised from 40 °C to 1000 °C at a heating rate of 10 °C / min for measurement.

[0009] The TG-DTA measurement is performed as follows. Cut out a position 5 mm to 10 mm from the surface layer of the polyurethane foam as a measurement sample, and perform TG-DTA measurement on the measurement sample at a heating rate of 10 °C / min and a measurement temperature range of 40 to 1000 °C. The TG-DTA measurement is performed under air. The reason for using the position 5 mm to 10 mm from the surface layer of the polyurethane foam as the measurement sample is to exclude the outermost layer from the measurement target. Any position within the range of 5 mm to 10 mm from the surface layer can be sampled as the measurement sample. By performing the TG-DTA measurement in this way, the weight reduction rate at 300 °C can be obtained based on the above formula. The polyurethane foam used in the TG-DTA measurement is the one prepared under the conditions described in the examples.

[0010] The weight reduction rate can be adjusted to a desired value by adjusting the composition in the foaming polyurethane composition. For example, it can be adjusted by the type and amount of the polyol compound used, the amount of the liquid flame retardant and the blowing agent, the isocyanate index, etc.

[0011] <Inorganic filler> The foaming polyurethane composition of the present invention substantially does not contain an inorganic filler. By substantially not containing an inorganic filler, it is possible to provide a foaming polyurethane composition that is unlikely to form precipitates during storage, has excellent handling properties, and can suppress wear of tools and the like used during use. Here, substantially not containing an inorganic filler means that, based on the total amount of the foaming polyurethane composition, the content of the inorganic filler is, for example, 5% by mass or less, preferably 1% by mass or less, more preferably 0.5% by mass or less.

[0012] The inorganic filler is an inorganic compound in the form of particles or fibers, and examples thereof include metals, metal oxides, metal hydroxides, ceramics, etc., and solid flame retardants, inorganic fillers other than solid flame retardants, etc. are exemplified. The above solid flame retardant is a solid flame retardant at 23°C, and examples thereof include antimony-containing flame retardants such as antimony oxide, antimonate, and pyroantimonate, metal hydroxide-based flame retardants such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide, boron-containing flame retardants such as lithium borate and sodium borate, phosphinic acid-based flame retardants, phosphate-containing flame retardants, bromine-containing flame retardants, red phosphorus, and the like. In addition to solid flame retardants, other inorganic fillers include, for example, silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, basic magnesium carbonate, calcium carbonate, magnesium carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, gypsum fiber, potassium salts such as calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass fiber, glass beads, silica pulp, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon pulp, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum porate, molybdenum sulfide, silicon carbide, stainless steel fiber, various magnetic powders, slag fiber, fly ash, silica alumina fiber, alumina fiber, silica fiber, zirconia fiber, etc.

[0013] <Polyol compounds> The polyol compound contained in the foamed polyurethane composition of the present invention is not particularly limited, but it is preferable to include polyether polyols, polyester polyols, etc. From the viewpoint of improving the flame retardancy of the resulting polyurethane foam, the polyol compound is preferably an aromatic polyester polyol, as described later, and a phthalic acid-based polyester polyol is preferred as the aromatic polyester polyol.

[0014] (Polyester polyol) The foamed polyurethane composition of the present invention preferably contains a polyester polyol. The inclusion of a polyester polyol makes it easier to improve flame retardancy. Examples of polyester polyols include aromatic polyester polyols and aliphatic polyester polyols. In particular, from the viewpoint of reducing the weight loss rate in TG-DTA measurement of the resulting polyurethane foam and improving flame retardancy, the polyester polyol is preferably an aromatic polyester polyol. The aromatic polyester polyol is preferably a condensate of an aromatic dicarboxylic acid such as o-phthalic acid (phthalic acid), m-phthalic acid (isophthalic acid), p-phthalic acid (terephthalic acid), or naphthalenedicarboxylic acid with a glycol. In particular, from the viewpoint of improving the flame retardancy of the polyurethane foam, the aromatic polyester polyol is preferably a phthalic acid-based polyester polyol, which is a condensate of phthalic acid and glycol, and even more preferably a p-phthalic acid-based polyester polyol, which is a condensate of p-phthalic acid and glycol. While the glycol is not particularly limited, it is preferable to use a low molecular weight aliphatic glycol known as a component of polyester polyols, such as ethylene glycol, propylene glycol, or diethylene glycol.

[0015] The polyester polyol may be a brominated polyester polyol. The brominated polyester polyol is a polyester polyol having an aromatic ring, and having a skeleton in which at least one bromine atom is bonded to the aromatic ring.

[0016] The hydroxyl value of the polyester polyol is preferably 100 to 400 mg KOH / g, and more preferably 150 to 350 mg KOH / g. In this specification, the hydroxyl value is the value measured in accordance with JIS K1557-1:2007.

[0017] From the viewpoint of improving the flame retardancy of the resulting polyurethane foam, the polyester polyol content on a basis of the total amount of polyol compounds is preferably more than 50% by mass, more preferably 70% by mass or more, even more preferably 75% by mass or more, and preferably 95% by mass or less.

[0018] (Polyether polyol) The polyol compound of the present invention preferably contains a polyether polyol. The inclusion of a polyether polyol improves the handling properties of the foamed polyurethane composition. Furthermore, the polyol compound of the present invention preferably contains both the polyester polyol and the polyether polyol mentioned above. This improves the handling properties of the foamed polyurethane composition and enhances the flame retardancy of the resulting polyurethane foam.

[0019] Polyether polyols are polyoxyalkylene polyols obtained by ring-opening addition polymerization of alkylene oxide to an initiator having two or more active hydrogen atoms. Examples of initiators include aliphatic polyhydric alcohols (e.g., glycols such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, 1,4-butanediol, 1,3-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexylene glycol, and cyclohexanedimethanol; triols such as trimethylolpropane and glycerin; tetrafunctional alcohols such as pentaerythritol; sugars such as sucrose and sorbitol); aliphatic amines (e.g., alkylenediamines such as ethylenediamine, propylenediamine, butylenediamine, hexamethylenediamine, and neopentyldiamine; alkanolamines such as monoethanolamine and diethanolamine); and aromatic amines (e.g., aniline, tolylenediamine, xylylenediamine, diphenylmethanediamine, Mannich condensates, etc.). These may be used individually or in combination of two or more.

[0020] As for polyether polyols, tolylenediamine-based polyether polyols, Mannich-based polyether polyols, sucrose-based polyether polyols, and sorbitol-based polyether polyols are preferred from the viewpoint of improving moldability during injection when foaming a foamed polyurethane composition and workability when spraying, with Mannich-based polyether polyols being more preferred among them. These polyol compounds are preferably used in combination with the above-mentioned aromatic polyester polyols from the viewpoint of providing excellent moldability, workability, and flame retardancy.

[0021] The tolylenediamine-based polyether polyols mentioned above are polyether polyols obtained using tolylenediamine as an initiator. Sucrose-based polyether polyols and sorbitol-based polyether polyols are similar. The above-mentioned Mannich-type polyether polyols are obtained using the Mannich reaction and are Mannich condensates having two or more hydroxyl groups in the molecule, or polyether polyols obtained by adding alkylene oxide to such Mannich condensates. More specifically, they are Mannich condensates obtained by the Mannich reaction of at least one of phenol and its alkyl-substituted derivatives, formaldehyde and alkanolamines, or polyether polyols obtained by ring-opening addition polymerization of these compounds with at least one of ethylene oxide and propylene oxide.

[0022] The polyether polyol may be a brominated polyether polyol. A brominated polyether polyol is a polyether polyol having an aromatic ring, and having a skeleton in which at least one bromine atom is bonded to the aromatic ring.

[0023] The hydroxyl value of the polyether polyol is preferably 200 to 1000 mg KOH / g, and more preferably 300 to 600 mg KOH / g.

[0024] The polyether polyol content is preferably 5% by mass or more, preferably less than 50% by mass, more preferably 30% by mass or less, and even more preferably 25% by mass or less, based on the total amount of polyol compounds.

[0025] (Polyisocyanate compounds) As the polyisocyanate compound contained in the foamed polyurethane composition, various polyisocyanate compounds such as aromatic, alicyclic, and aliphatic compounds having two or more isocyanate groups can be used. Preferably, liquid diphenylmethane diisocyanate (MDI) is used due to its ease of handling, rapid reaction, excellent physical properties of the resulting polyurethane foam, and low cost. Examples of liquid MDI include crude MDI (also called polymeric MDI). Specific commercially available liquid MDI products include "44V-10" and "44V-20" (manufactured by Sumika Covestro Urethane Co., Ltd.) and "Millionate MR-200" (Nippon Polyurethane Industry Co., Ltd.). Alternatively, uretonimine-containing MDI (for example, "Millionate MTL": manufactured by Nippon Polyurethane Industry Co., Ltd.) may also be used. In addition to liquid MDI, other polyisocyanate compounds may be used in combination, and any polyisocyanate compound known in the field of polyurethanes can be used without limitation.

[0026] The isocyanate index range of the foamed polyurethane composition of the present invention is preferably 150 to 700, more preferably 200 to 500, and even more preferably 250 to 450. By setting the isocyanate index within this range, it becomes easier to reduce the weight loss rate at 300°C in the TG-DTA described above. The isocyanate index (INDEX) is calculated using the following method.

[0027] INDEX = Equivalents of isocyanate ÷ (Equivalents of polyol + Equivalents of water) × 100 Here, Equivalent weight of isocyanate = Number of polyisocyanates used × NCO content (%) × 100 / Molecular weight of NCO The equivalent weight of the polyol = OHV × the amount of polyol used ÷ the molecular weight of KOH, where OHV is the hydroxyl value of the polyol (mgKOH / g). Equivalent amount of water = Number of parts of water used × Number of OH groups in water / Molecular weight of water In the above formula, the unit of the number of parts used is weight (g), the molecular weight of the NCO group is 42, the NCO content is the proportion of NCO groups in the polyisocyanate compound expressed in mass%, and for the sake of unit conversion in the above formula, the molecular weight of KOH is assumed to be 56100, the molecular weight of water is assumed to be 18, and the number of OH groups in water is assumed to be 2.

[0028] (Liquid flame retardant) The foamed polyurethane composition of the present invention contains a liquid flame retardant at room temperature, where room temperature is defined as 23°C. The inclusion of a liquid flame retardant makes it easier to adjust the weight loss rate in the TG-DTA described above, and its liquid state also helps to suppress wear on equipment and other items used when the foamed polyurethane composition is in use. Examples of liquid flame retardants include phosphate ester-based flame retardants such as monophosphate esters and condensed phosphate esters. Examples of monophosphate esters, though not particularly limited, include trimethyl phosphate, triethyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, and tris(β-chloropropyl) phosphate. Examples of condensed phosphate esters are not particularly limited, but include resorcinol polyphenyl phosphate (trade name CR-733S), bisphenol A polycrezyl phosphate (trade name CR-741), and aromatic condensed phosphate esters (trade name CR747). The liquid flame retardant content is preferably 35 parts by mass or more, more preferably 40 parts by mass or more, even more preferably 50 parts by mass or more, and preferably 120 parts by mass or less, and more preferably 100 parts by mass or less, per 100 parts by mass of the polyol compound. By keeping the liquid flame retardant content below these upper limits, the amount of polyol and polyisocyanate compounds used can be relatively increased, making it easier to form polyurethane foam. If the liquid flame retardant content is above these lower limits, it becomes easier to reduce the weight loss rate in TG-DTA measurement of polyurethane foam formed from the foamable polyurethane composition. Furthermore, by keeping the liquid flame retardant content above these lower limits while adjusting the isocyanate index to the above-mentioned range, it becomes easier to more effectively reduce the weight loss rate in TG-DTA measurement of polyurethane foam, thereby improving flame retardancy.

[0029] (Foaming agent) Specific examples of blowing agents include, for example, water, low-boiling-point hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, and hydrofluoroolefins. Furthermore, blowing agents include organic physical blowing agents such as mixtures of these compounds, and inorganic physical blowing agents such as nitrogen gas, oxygen gas, argon gas, and carbon dioxide gas. Examples of the low-boiling hydrocarbons mentioned above include propane, butane, pentane, hexane, heptane, cyclopropane, cyclobutane, cyclopentane, cyclohexane, and cycloheptane. Examples of the above-mentioned chlorinated aliphatic hydrocarbon compounds include dichloroethane, propyl chloride, isopropyl chloride, butyl chloride, isobutyl chloride, pentyl chloride, and isopentyl chloride. Examples of the fluorine compounds mentioned above include CHF3, CH2F2, and CH3F. Examples of the above-mentioned hydrochlorofluorocarbon compounds include trichloromonofluoromethane, trichlorotrifluoroethane, and dichloromonofluoroethane (e.g., HCFC141b (1,1-dichloro-1-fluoroethane), HCFC22 (chlorodifluoromethane), HCFC142b (1-chloro-1,1-difluoroethane)). Examples of the above-mentioned hydrofluorocarbons include HFC-245fa (1,1,1,3,3-pentafluoropropane) and HFC-365mfc (1,1,1,3,3-pentafluorobutane). Examples of the ether compounds mentioned above include diisopropyl ether. Examples of the above-mentioned hydrofluoroolefins include HFO-1233zd(E) (trans-1-chloro-3,3,3-trifluoropropene), HFO-1234yf (2,3,3,3-tetrafluoro-1-propene), and HFO-1224yd(Z) (trans-1-chloro-2,3,3,3-tetrafluoropropene).

[0030] Among the blowing agents mentioned above, considering environmental issues such as global warming, it is preferable that the blowing agent in the present invention includes one with a low GWP (Global Warming Potential), such as hydrofluoroolefin. Specifically, the GWP of the blowing agent is preferably 10 or less. Examples of blowing agents with a GWP of 10 or less include hydrofluoroolefins such as HFO-1233zd(E) (trans-1-chloro-3,3,3-trifluoropropene), HFO-1234yf (2,3,3,3-tetrafluoro-1-propene), HFO-1224yd(Z) (trans-1-chloro-2,3,3,3-tetrafluoropropene), and HFO-1336mzz(Z) (cis-1,1,1,4,4,4-hexafluorobuta-2-ene). In addition to these hydrofluoroolefins, other blowing agents with a GWP of 10 or less include water and methyl formate.

[0031] In the present invention, the foaming agent preferably contains water, and more specifically, a foaming agent comprising water in combination with at least one compound selected from the low-boiling hydrocarbons, chlorinated aliphatic hydrocarbon compounds, fluorine compounds, hydrochlorofluorocarbon compounds, hydrofluorocarbons, ether compounds, and hydrofluoroolefins mentioned above is preferred. As water, for example, ion-exchanged water, distilled water, etc., can be used as appropriate. The amount of water per 100 parts by mass of polyol compound is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, even more preferably 0.1 parts by mass or more, and preferably 3.0 parts by mass or less, more preferably 2.0 parts by mass or less, even more preferably 1.5 parts by mass or less, and even more preferably 0.7 parts by mass or less. If the water content is above these lower limits, the foamable polyurethane composition becomes easier to foam, and the density can be easily adjusted to the desired range. Also, if the water content is below these upper limits, the weight loss rate of the polyurethane foam in TG-DTA can be easily adjusted to the desired range mentioned above.

[0032] In the present invention, the foaming agent preferably contains a hydrofluoroolefin, and more preferably contains both the hydrofluoroolefin and the water described above. The amount of hydrofluoroolefin per 100 parts by mass of the polyol compound is preferably 10 to 60 parts by mass, more preferably 25 to 50 parts by mass, and even more preferably 35 to 45 parts by mass.

[0033] (catalyst) The foamed polyurethane composition of the present invention contains a catalyst. The catalyst may contain, for example, one or both of a urethane catalyst and a trimerizing catalyst, and it is preferable that it contains both. The catalyst contained in the foamed polyurethane composition shall not be considered an inorganic filler in the present invention.

[0034] Urethane catalysts are catalysts that promote the reaction between polyol compounds and polyisocyanate compounds. Specifically, examples include amino compounds, tin compounds, bismuth compounds, and acetylacetone metal salts. Examples of the aforementioned amino compounds include pentamethyldiethylenetriamine, triethylamine, N-methylmorpholine bis(2-dimethylaminoethyl) ether, bis(2-dimethylaminoethyl) ether, N,N,N',N”,N”-pentamethyldiethylenetriamine, N,N,N'-trimethylaminoethyl-ethanolamine, bis(2-dimethylaminoethyl) ether, N-methyl-N',N'-dimethylaminoethylpiperazine, imidazole compounds in which the secondary amine functional group in the imidazole ring is substituted with a cyanoethyl group, N,N-dimethylcyclohexylamine, diazabicycloundecene, triethylenediamine, tetramethylethylenediamine, tetramethylhexamethylenediamine, 1-methylimidazole, trimethylaminoethylpiperazine, and tripropylamine. Examples of tin compounds include stannous octoate, dibutyltin diacetate, and dibutyltin dilaurate. Examples of bismuth compounds include bismuth neodecanoate and bismuth octoate. Examples of acetylacetone metal salts include aluminum acetylacetone, iron acetylacetone, copper acetylacetone, zinc acetylacetone, beryllium acetylacetone, chromium acetylacetone, indium acetylacetone, manganese acetylacetone, molybdenum acetylacetone, titanium acetylacetone, cobalt acetylacetone, vanadium acetylacetone, and zirconium acetylacetone. The urethane catalyst may be used alone or in combination of two or more types.

[0035] There are no particular limitations on the amount of urethane catalyst blended in the foamed polyurethane composition, but it is preferably in the range of 0.3 to 10 parts by mass, more preferably in the range of 0.5 to 8 parts by mass, and even more preferably in the range of 1 to 5 parts by mass, per 100 parts by mass of the total of the polyol compound and the polyisocyanate compound. By keeping it within the above range, the reaction between the polyol compound and the polyisocyanate compound can be promoted at an appropriate reaction rate.

[0036] Trimerization catalysts are catalysts that promote trimerization, which involves the formation of isocyanurate bonds. In polyurethane resins, the flame retardancy of polyurethane foam is improved by the promotion of trimerization. As trimerization catalysts, aromatic compounds such as tris(dimethylaminomethyl)phenol, 2,4-bis(dimethylaminomethyl)phenol, and 2,4,6-tris(dialkylaminoalkyl)hexahydro-S-triazine, alkali metal salts such as potassium acetate, sodium acetate, potassium 2-ethylhexanoate, sodium 2-ethylhexanoate, potassium octoate, potassium formate, and sodium octoate, aziridines such as 2-ethylaziridine, lead compounds such as lead naphthenate and lead octoate, alkoxide compounds such as sodium methoxide, phenolate compounds such as potassium phenoxide, tertiary ammonium salts such as trimethylammonium salt, triethylammonium salt, and triphenylammonium salt, and quaternary ammonium salts such as tetramethylammonium salt, tetraethylammonium, and tetraphenylammonium salt can be used. The trimerizing catalyst may be used alone or in combination of two or more types.

[0037] The amount of trimerizing catalyst is not particularly limited, but it is preferably 0.3 to 10 parts by mass, more preferably 0.5 to 8 parts by mass, and even more preferably 0.8 to 5 parts by mass, per 100 parts by mass of the total of the polyol compound and the polyisocyanate compound. By keeping the amount of trimerizing catalyst within the above range, isocyanurate bonds are appropriately formed, improving flame retardancy. Furthermore, from the viewpoint of improving the curing speed and flame retardancy of the urethane, the total amount of catalyst is preferably 0.5 to 20 parts by mass, more preferably 1 to 16 parts by mass, and even more preferably 2 to 10 parts by mass, per 100 parts by mass of the total of the polyol compound and the polyisocyanate compound.

[0038] (Foam stabilizer) The foamed polyurethane composition may optionally contain a foam stabilizer. Examples of foam stabilizers include polyoxyalkylene foam stabilizers such as polyoxyalkylene alkyl ethers, and surfactants such as silicone-based foam stabilizers such as organopolysiloxanes. Furthermore, silicone-based foam stabilizers may include graft copolymers of polydimethylsiloxane and polyethylene glycol. The foam stabilizer content is preferably 0.01 to 10 parts by mass, more preferably 0.1 to 8 parts by mass, and even more preferably 0.5 to 5 parts by mass, per 100 parts by mass of the polyol compound. The foam stabilizer may be used alone or two or more types may be used.

[0039] The foamed polyurethane composition may contain additives such as phenolic, amine, or sulfur-based antioxidants, heat and light stabilizers, metal damage inhibitors, antistatic agents, crosslinking agents, lubricants, softeners, pigments, and tackifying resins, to the extent that they do not impede the effects of the present invention.

[0040] The foamed polyurethane composition of the present invention hardens through a reaction between a polyol compound and a polyisocyanate compound, and therefore its viscosity changes over time. For this reason, before using the foamed polyurethane composition, it is preferable to divide it into two or more parts to prevent the reaction and hardening. Then, when using the foamed polyurethane composition, it is preferable to combine the two or more parts into one.

[0041] When dividing a foamed polyurethane composition into two or more parts, the curing reaction should be initiated only after the components of the divided foamed polyurethane composition are mixed, rather than each component curing on its own. Typically, a foamed polyurethane composition is divided into a polyol composition containing a polyol compound and a polyisocyanate composition containing a polyisocyanate compound.

[0042] The above-mentioned liquid flame retardant, blowing agent, catalyst, and optionally added foam stabilizer, which are at room temperature, may be contained in the polyol composition, in the polyisocyanate composition, or provided separately from the polyol composition and the polyisocyanate composition, but it is preferable that they be contained in the polyol composition. In other words, the polyol composition is preferably a polyol premix containing a polyol compound, a catalyst, a blowing agent, and a liquid flame retardant, and the foamed polyurethane composition of the present invention is preferably a mixture of the polyol premix and a polyisocyanate compound.

[0043] The polyurethane foam of the present invention is not particularly limited, but in cases where it is divided into two or more parts, such as a two-component foamable polyurethane composition, it can be obtained by, for example, preparing two or more divided components, such as a polyol composition and a polyisocyanate composition, by mixing the components in advance, mixing them, and foaming them. The mixing of each component and foaming can be carried out by known methods. For example, it can be obtained using known equipment such as a high-pressure foamer, a low-pressure foamer, a spray foamer, or a hand mixer. In the case of a one-component type, one method is to foam the foamable polyurethane composition obtained by mixing the components constituting the foamable polyurethane composition using a known method.

[0044] (Application) The uses of the foamed polyurethane composition of the present invention are not particularly limited, but it can be used to fill cavities in structures such as buildings, furniture, automobiles, trains, and ships, or to spray onto such structures. In particular, it is preferable to use it for spraying onto structures, that is, as a foamed polyurethane composition for spraying. Spraying can be carried out using a spraying device (e.g., GRACO A-25) and a spray gun (e.g., Gasmar D-gun). Spraying can be performed by temperature-controlled polyol composition and polyisocyanate composition in separate containers within the spraying device, mixing them by collision at the tip of the spray gun, and atomizing the mixture with air pressure. Spraying devices and spray guns are well-known and commercially available products can be used.

[0045] [Polyurethane foam] The polyurethane foam of the present invention is formed from the above-described foamable polyurethane composition, and more specifically, is obtained by foaming and curing the foamable polyurethane composition. Polyurethane foam has a weight loss rate of 40% or less at 300°C as measured by TG-DTA. If the weight loss rate exceeds 40%, the polyurethane foam becomes more susceptible to oxidative decomposition in the event of a fire, reducing its flame retardancy. From the viewpoint of improving flame retardancy, the above weight loss rate is preferably 39% or less, and more preferably 38% or less. The lower the weight loss rate, the more oxidative decomposition is suppressed and the higher the flame retardancy, so 0% is preferable.

[0046] The density of polyurethane foam is not particularly limited, but is typically between 20 and 200 kg / m³. 3 It is preferable that the density be within this range. 3 By doing the following, the polyurethane foam becomes lighter, improving its ease of application to structures. Also, 20 kg / m 3 By doing so, the desired flame retardancy is more easily achieved. From these perspectives, the density of the polyurethane foam should be 25-100 kg / m³. 3 It is more preferable that the range be 25-80 kg / m 3 It is even more preferable that the density be within this range. The density of the polyurethane foam can be measured in accordance with JIS K7222. [Examples]

[0047] The present invention will be described in more detail by reference to examples, but the present invention is not limited in any way by these examples.

[0048] The details of each component used in each example and comparative example are as follows. (1) Polyol compounds • p-phthalate-based polyester polyol (manufactured by Hitachi Chemical Co., Ltd., product name: SV-208, hydroxyl value = 235 mg KOH / g) • Mannich-type polyether polyol (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., product name: DK3776, hydroxyl value = 350 mg KOH / g) • Sucrose-based polyether polyol (manufactured by AGC, product name: EL-100S, hydroxyl value = 450 mg KOH / g) • Ethylenediamine-based polyether polyol (manufactured by AGC, product name: Exenol 750ED, hydroxyl value = 760 mg KOH / g) • Tolylenediamine-based polyether polyol (manufactured by Mitsui Chemicals, product name: GR-40A, hydroxyl value = 400 mg KOH / g) (2) Liquid flame retardant • Phosphate ester-based flame retardant <Tris(β-chloropropyl) phosphate> (manufactured by Daihachi Chemical Co., Ltd., product name: TMCPP) (3) Foam stabilizer • Silicone-based foam stabilizer (manufactured by Toray Dow Corning, product name: SH-193) (4) Catalyst (i) Trimerization catalyst • Quaternary ammonium salt (manufactured by Evonik Japan, product name: TMR-7) (ii) Urethane catalyst • Imidazole compound (manufactured by Kao Corporation, product name: KL No. 390) • Non-imidazole compound (manufactured by Evonik Japan, product name: PC-201) • Bismuth compound (manufactured by Nitto Chemical Co., Ltd., product name: Neostan U-600) (5) Foaming agent ·water • HFO-1233zd <Hydrofluoroolefin> (Honeywell, product name: Solstice LBA) GWP=1 (6) Polyisocyanate compounds • MDI (manufactured by Sumika Covestro Urethane Co., Ltd., product name: 44V-20)

[0049] The measurement methods for each physical property and characteristic are as follows.

[0050] [Weight reduction rate] TD-DTA measurements were performed on the polyurethane foams prepared in each example and comparative example as follows. The apparatus used for TD-DTA measurement was the TG / DTA-6200 manufactured by Seiko Electronics Industries Ltd. A sample was cut from a polyurethane foam at a depth of 5 mm to 10 mm from the surface and used as the measurement sample. TG / DTA measurements were performed on this sample (1.5 mg) under air conditions at a heating rate of 10°C / min within a measurement temperature range of 40 to 1000°C. The weight loss rate was calculated using the following formula (1) from the weight of the sample (polyurethane foam) before measurement and the weight of the sample at 300°C during the TG-DTA measurement. Weight loss rate at 300°C (%) = 100 × (Weight of sample before test - Weight of sample at 300°C) / Weight of sample before measurement ... Equation (1)

[0051] [Flame retardancy test according to UL94] Polyurethane foam was cut out to create measurement samples measuring 125 mm x 13 mm x 13 mm. These measurement samples were subjected to a combustion test in accordance with UL standard UL94. Five samples of each measurement were burned, and their combustion performance was evaluated based on the average burning time according to the following criteria. Equivalent to V-0 ×...Inferior performance compared to the V-0

[0052] [Heat generation test (CCM: Corn Calorimeter)] Polyurethane foam, prepared by spraying onto gypsum boards manufactured in each example and comparative example, was cut into pieces measuring 100 mm in length, 100 mm in width, and 32.5 mm in thickness (12.5 mm of gypsum board and 20 mm of polyurethane foam) to prepare samples for cone calorimeter testing. These test samples were measured for a radiant thermal intensity of 50 kW / m² in accordance with the ISO-5660 test method.2 The maximum heat generation rate was measured when heated for 5 minutes and evaluated according to the following criteria. 〇...Maximum heating rate is 150 kW / m 2 below ×...Maximum heating rate is 150 kW / m 2 super

[0053] [Example 1] A polyol premix was prepared by mixing a polyol compound, liquid flame retardant, foam stabilizer, catalyst, and blowing agent according to the formulations shown in Table 1. The polyol premix and polyisocyanate compound (MDI) were introduced into a spraying apparatus (GRACO: A-25), the temperature was controlled within the apparatus, and the mixture was sprayed onto a 12.5 mm thick gypsum board using a spray gun (Gasmar: D-gun) to produce a polyurethane foam consisting of the foamable polyurethane composition described in Table 1. The polyurethane foam was then used for various evaluations. The results are shown in Table 1.

[0054] [Examples 2-3, Comparative Examples 1-2] A polyurethane foam was obtained in the same manner as in Example 1, except that the formulation was changed as shown in Table 1. The polyurethane foam was used for each evaluation. The results are shown in Table 1.

[0055] [Table 1]

[0056] As shown in each example, the polyurethane foam formed from the foamable polyurethane composition of the present invention exhibited a low weight loss rate at 300°C and good evaluation in the flame retardancy test (UL94). Furthermore, the foamable polyurethane compositions of each example contained substantially no inorganic fillers, making them easy to handle as they were less prone to precipitation during storage, and also suppressing wear on spraying equipment and other devices used during application. In contrast, the polyurethane foam formed from the comparative example's foamable polyurethane composition showed a high weight loss rate at 300°C and poor results in the flame retardancy test (UL94).

Claims

1. A foamed polyurethane composition for use in spray applications, comprising a polyol compound, a polyisocyanate compound, a catalyst, a blowing agent, and a liquid flame retardant, In the total amount of the aforementioned foamed polyurethane composition, the inorganic filler content is 0.5% by mass or less. The polyol compound is a condensate of an aromatic dicarboxylic acid and a glycol, and contains a phthalic acid-based polyester polyol in which the aromatic dicarboxylic acid consists solely of phthalic acid, and the content of the phthalic acid-based polyester polyol is 80% by mass or more based on the total amount of the polyol compound. The foaming agent comprises a hydrofluoroolefin and water, wherein the water content is 1.5 parts by mass or less per 100 parts by mass of the polyol compound. The isocyanate index is between 250 and 700. The content of the liquid flame retardant is 35 parts by mass or more and 100 parts by mass or less per 100 parts by mass of the polyol compound. A foamed polyurethane composition wherein the polyurethane foam formed from the foamed polyurethane composition has a weight loss rate of 40% or less at 300°C when measured by TG-DTA under the following conditions. (TG-DTA measurement conditions) A sample is cut from a polyurethane foam at a depth of 5 mm to 10 mm from the surface, and TG-DTA measurement is performed on the sample at a heating rate of 10°C / min and within a measurement temperature range of 40 to 1000°C.

2. The foamable polyurethane composition according to claim 1, which is a mixture of a polyol premix containing a polyol compound, a catalyst, a blowing agent, and a liquid flame retardant, and a polyisocyanate compound.

3. The foamed polyurethane composition according to claim 1 or 2, wherein the polyol compound contains a polyether polyol.

4. The foamed polyurethane composition according to any one of claims 1 to 3, wherein the catalyst contains a trimerizing catalyst.

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