Polyol composition, polyurethane resin composition, and polyurethane foam

Abstract

To provide a polyol composition that can form polyurethane foams with a high expansion ratio, and can suppress bumping even under high temperatures.SOLUTION: A polyol composition for obtaining a polyurethane foam by reacting with a polyisocyanate, the polyol composition containing a polyol, a foaming agent, a filler, a catalyst, and a low molecular weight polyhydric alcohol, the foaming agent comprising a hydrofluoroolefin having a boiling point of 40°C. or less, and a content of the low molecular weight polyhydric alcohol is less than 6 mass% based on a total amount of the polyol composition.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a polyol composition, a polyurethane resin composition, and a polyurethane foam.

Background Art

[0002] Due to its excellent heat insulation and adhesiveness, polyurethane foam is used, for example, as a heat insulating material for buildings such as apartment houses, detached houses, various facilities in schools, and commercial buildings. Polyurethane foam is obtained by mixing a polyol composition and an isocyanate and foaming them, and spraying them onto objects such as ceilings, walls, and roofs using a spraying device or the like. Since such polyurethane foam is used in buildings, it is required to have flame retardancy in order to prevent fire from spreading and causing a conflagration in case of a fire.

[0003] As a polyol composition for obtaining the above-described polyurethane foam, for example, as described in Patent Documents 1 and 2, a polyol composition containing a foaming agent, a catalyst, and a flame retardant is known, and such a polyol composition may contain HFO as a foaming agent and a filler as a flame retardant, respectively.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document - 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, in order to obtain polyurethane foams with a high foaming ratio, the above-mentioned polyol composition is being considered to contain not only HFO as a foaming agent but also a low molecular weight polyhydric alcohol. On the other hand, polyol compositions containing fillers may precipitate or aggregate when stored as a solution, so stirring is necessary before foaming. However, since both HFO and low molecular weight polyhydric alcohols have low boiling points, if a solution of a polyol composition containing these substances becomes hot in the summer, stirring the solution will cause it to boil, which poses a safety problem. Therefore, the object of the present invention is to provide a polyol composition that can form a polyurethane foam with a high foaming ratio and suppresses bumping even at high temperatures. [Means for solving the problem]

[0006] As a result of diligent research, the inventors have found a solution to the above problem by reducing the content of low molecular weight polyhydric alcohols with a small number of carbon atoms in a polyol composition containing a polyol, a foaming agent, a filler, a catalyst, and a low molecular weight polyhydric alcohol, thereby completing the present invention. The present invention provides the following [1] to [6].

[0007] [1] A polyol composition for reacting with a polyisocyanate to obtain a polyurethane foam, wherein the polyol composition contains a polyol, a blowing agent, a filler, a catalyst, and a low molecular weight polyhydric alcohol having less than 6 carbon atoms, the blowing agent contains a hydrofluoroolefin with a boiling point of 40°C or less, and the content of the low molecular weight polyhydric alcohol is less than 6% by mass on a basis of the total amount of the polyol composition. [2] The polyol composition according to [1], wherein the content of polyols having 4 or fewer carbon atoms among the low molecular weight polyols is less than 3.5% by mass on a basis of the total amount of the polyol composition. [3] The polyol composition according to [1] or [2], wherein the content of polyols having 2 or fewer carbon atoms among the low molecular weight polyols is less than 2% by mass on a basis of the total amount of the polyol composition. [4] The polyol composition according to [1] or [2], wherein the low molecular weight polyhydric alcohol does not contain a polyhydric alcohol having 2 or fewer carbon atoms. A polyurethane resin composition comprising the polyol composition described in [5][1] or [2] and a polyisocyanate. A polyurethane foam obtained by reacting and foaming the polyurethane resin composition described in [6][5]. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a polyol composition that can form a polyurethane foam with a high expansion ratio and in which bumping is suppressed even at high temperatures. [Modes for carrying out the invention]

[0009] [Polyol composition] The polyol composition of the present invention contains a polyol, a foaming agent, a filler, a catalyst, and a low molecular weight polyhydric alcohol.

[0010] <Low molecular weight polyhydric alcohols> The polyol composition of the present invention contains a low molecular weight polyhydric alcohol, but the content of the low molecular weight polyhydric alcohol in the polyol composition is less than 6% by mass on a basis of the total polyol composition. If the content of the low molecular weight polyhydric alcohol is 6% by mass or more on a basis of the total polyol composition, bumping cannot be suppressed when the polyol composition is stirred at high temperatures. From this viewpoint, among the low molecular weight polyhydric alcohols, the content of polyhydric alcohols having 4 or fewer carbon atoms is preferably 5% by mass or less on a basis of the total polyol composition, and more preferably less than 3.5% by mass. From the viewpoint of making it easier to more effectively suppress bumping of the polyol composition, it is preferable to reduce the content of polyhydric alcohols having 2 or fewer carbon atoms among the low molecular weight polyhydric alcohols, and specifically, it is preferably less than 3% by mass on a basis of the total polyol composition, and more preferably less than 2% by mass.

[0011] From the viewpoint of suppressing bumping, the polyol composition of the present invention preferably does not contain polyhydric alcohols having 2 or fewer carbon atoms. "Does not contain" means that it is 0% by mass based on the total amount of the polyol composition. On the other hand, the polyol composition of the present invention can form a polyurethane foam with a high foaming ratio by containing a certain amount or more of polyhydric alcohol having 4 or fewer carbon atoms. From this perspective, the content of polyhydric alcohol having 4 or fewer carbon atoms may be 1.0% by mass or more on a basis of the total amount of the polyol composition, preferably 2.0% by mass or more, more preferably 2.5% by mass or more, and even more preferably 3.0% by mass or more. In this specification, "low molecular weight polyhydric alcohol" refers to an alcohol having fewer than 6 carbon atoms and being divalent or greater. The low molecular weight polyhydric alcohol contained in the polyol composition of the present invention may include, in addition to polyhydric alcohols having 4 or fewer carbon atoms, a low molecular weight polyhydric alcohol having 5 carbon atoms, as long as it does not hinder the effects of the present invention. The low molecular weight polyhydric alcohol is not particularly limited as long as it is divalent or higher, but for example, it is a divalent to tetravalent, preferably divalent to trivalent, and more preferably divalent.

[0012] Among the low molecular weight polyhydric alcohols that can be contained in the polyol composition of the present invention, the structure consisting of groups other than hydroxyl groups (hereinafter also referred to as "structure A") may consist of hydrocarbon groups or a combination of hydrocarbon groups and ether bonds, but a combination of hydrocarbon groups and ether bonds is preferred. The hydrocarbon group is preferably an aliphatic group. If the hydrocarbon group is an aliphatic group, it may be a saturated aliphatic group or an unsaturated aliphatic group. The structure of these aliphatic groups may be a linear structure, a branched structure, a cyclic structure, or a combination of two or more selected from linear, branched, and cyclic structures. In the present invention, the hydrocarbon group constituting the low molecular weight polyhydric alcohol is more preferably a saturated aliphatic group, and even more preferably a linear saturated aliphatic group, from the viewpoint of improving the compatibility of the foaming agent with the polyol composition and effectively suppressing bumping of the polyol composition. Furthermore, the position of the hydroxyl group in the low molecular weight polyhydric alcohol is not particularly limited, but it is preferable that it be located at both ends of structure A.

[0013] As low molecular weight polyhydric alcohols with 4 or fewer carbon atoms, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, diethylene glycol, propylene glycol, 1,3-propanediol, glycerin, ethylene glycol, methanediol, etc., can be used. Among these, 1,3-butanediol, 1,4-butanediol, 1,3-propanediol, diethylene glycol, and ethylene glycol are preferred, and among these, 1,3-propanediol, 1,4-butanediol, diethylene glycol, and ethylene glycol are more preferred from the viewpoint of reducing the content of low molecular weight polyhydric alcohols with 2 or fewer carbon atoms. Examples of low molecular weight polyhydric alcohols with 5 carbon atoms include pentanediol, isoprene glycol, and neopentyl glycol. Low molecular weight polyhydric alcohols may be used alone or in combination of two or more. More specifically, the polyol composition may contain either a low molecular weight polyhydric alcohol having 4 or fewer carbon atoms or a low molecular weight polyhydric alcohol having 5 carbon atoms, or it may contain one or more low molecular weight polyhydric alcohols having 4 or fewer carbon atoms and one or more low molecular weight polyhydric alcohols having 5 carbon atoms.

[0014] The content of low molecular weight polyhydric alcohols in the polyol composition of the present invention (total content of low molecular weight polyhydric alcohols having 4 or fewer carbon atoms and low molecular weight polyhydric alcohols having 5 carbon atoms) is less than 6% by mass on a basis of the total polyol composition, but is preferably less than 5% by mass, more preferably 4.2% by mass or less, and even more preferably 3.8% by mass or less. By keeping the content of low molecular weight polyhydric alcohols below the above upper limit, bumping of the polyol composition can be suppressed when the composition is stirred. Furthermore, the content of low molecular weight polyhydric alcohols is preferably 1% by mass or more on a basis of the total polyol composition, more preferably 2% by mass or more, even more preferably 2.5% by mass or more, and even more preferably 3.2% by mass or more. By keeping the total content of low molecular weight polyhydric alcohols below the above lower limit, a polyurethane foam with a high foaming ratio can be formed.

[0015] <Foaming agent> The blowing agent used in the present invention contains hydrofluoroolefin (hereinafter also referred to as "HFO") having a boiling point of 40°C or lower from the viewpoint of foaming properties. The blowing agent promotes foaming when the polyol composition of the present invention is mixed with a polyisocyanate to produce a polyurethane foam. In addition to low molecular weight polyhydric alcohols, when such a low boiling point blowing agent is contained in the polyol composition, bumping of the polyol composition is likely to occur during stirring at high temperature. However, even if the polyol composition of the present invention contains such a low boiling point blowing agent, by reducing the content of the low molecular weight polyhydric alcohol, bumping can be suppressed even during stirring at high temperature. When the boiling point of the HFO used in the present invention exceeds 40°C, the foaming property deteriorates, making it difficult to obtain a foam with an appropriate density. From the viewpoint of better foaming properties, the boiling point of HFO is preferably 30°C or lower, more preferably 25°C or lower, and even more preferably 20°C or lower. Among blowing agents, HFO has high stability as a blowing agent, is less likely to have its catalytic activity reduced, and further has a low environmental load, so it can be suitably used. The lower limit of the boiling point of HFO is not particularly limited, but from the viewpoint of practicality, it is, for example, 10°C or higher, preferably 15°C or higher.

[0016] Examples of HFO include fluoroalkenes having about 3 to 6 carbon atoms. Also, HFO may be a hydrochlorofluoroolefin having a chlorine atom, and thus may be a chlorofluoroalkene having about 3 to 6 carbon atoms. Examples of HFO include trifluoropropene, tetrafluoropropene such as HFO-1234, pentafluoropropene such as HFO-1225, chlorodifluoropropene, chlorotrifluoropropene such as HFO-1233, and chlorotetrafluoropropene. More specifically, 3,3,3-trifluoropropene (HFO-1243zf, boiling point: -18 °C), trans-1,3,3,3-tetrafluoropropene (HFO-1234ze(E), boiling point: -19 °C), cis-1,3,3,3-tetrafluoropropene (HFO-1234ze(Z), boiling point: 10 °C), 2,3,3,3-tetrafluoropropene (HFO-1234yf, boiling point: -29 °C), 1,1,3,3-tetrafluoropropene (boiling point: 4 °C), trans-1,2,3,3,3-pentafluoropropene (HFO-1225ye(E), boiling point: -10 °C), cis-1,2,3,3,3-pentafluoropropene (HFO-1225ye(Z), boiling point: -19 °C), 1,1,3,3,3-pentafluoropropene (HFO-1225zc, boiling point: -21 °C), 1,1,2,3,3-pentafluoropropene (HFO-1225yc, boiling point: 2 °C), trans-1-chloro-3,3,3-trifluoropropene (HFO-1233zd(E), boiling point: 18 °C), cis-1,3,3,3-tetrafluoropropene (HFO-1234ze(Z), boiling point: 39 °C), 1,1,1,4,4,4-hexafluorobut-2-ene (HFO-1336mzz, boiling point: 33 °C), 1-chloro-2,3,3,3,-tetrafluoropropene(Z) (HFO-1224yd(Z), boiling point: 14 °C), etc. are exemplified. Among these, HFO-1233zd(E) is preferable. These HFOs may be used alone or in combination of two or more.

[0017] The content of HFO is not particularly limited, and with respect to 100 parts by mass of the polyol, 19 to 75 parts by mass is preferable, 29 to 67 parts by mass is more preferable, and 34 to 58 parts by mass is still more preferable. When the content of HFO is at least the above lower limit, foaming is promoted, the foaming property becomes good, and a polyurethane foam with a high foaming ratio can be formed. On the other hand, when the content of HFO is at most the above upper limit, it is possible to suppress the excessive progress of foaming.

[0018] Furthermore, water may be included as a blowing agent. Water is easy to handle, and its inclusion makes it easier to adjust the isocyanate index. When water is included together with HFO as a blowing agent, for example, ion-exchanged water or distilled water can be used as appropriate. The amount of water is not particularly limited, but is preferably 0.1 to 5 parts by mass, more preferably 0.2 to 3 parts by mass, and even more preferably 0.3 to 2 parts by mass per 100 parts by mass of polyol. If the amount of blowing agent is above the lower limit, foaming is promoted, resulting in good foaming properties and the formation of a polyurethane foam with a high foaming ratio. On the other hand, if the amount of blowing agent is below the upper limit, excessive foaming can be suppressed.

[0019] Furthermore, the polyol composition may contain blowing agents other than water and HFO, as long as it achieves the effects of the present invention. Examples of blowing agents include low-boiling hydrocarbons such as propane, butane, pentane, cyclopropane, and cyclobutane, and chlorinated aliphatic hydrocarbon compounds such as propyl chloride and isopropyl chloride, which have a boiling point of 40°C or less. When these blowing agents are included, the amount of blowing agents should be, for example, 30% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less, and most preferably 0% by mass, based on the total amount of blowing agents.

[0020] <Polyol> The polyol is not particularly limited, but examples include polyether polyols and polyester polyols. Note that the polyol is a polyol other than the low molecular weight polyhydric alcohols mentioned above. From the viewpoint of improving the flame retardancy of the polyurethane foam, it is preferable that the polyol includes polyester polyol. Similarly, from the viewpoint of improving the flame retardancy of the polyurethane foam, it is preferable that the amount of polyester polyol be 20 parts by mass or more, more preferably 50 parts by mass or more, even more preferably 80 parts by mass or more, and particularly preferably 100 parts by mass out of 100 parts by mass of polyol.

[0021] The average hydroxyl value of the polyol used in the present invention is preferably 100 to 500 mg KOH / g, more preferably 150 to 450 mg KOH / g, and even more preferably 180 to 400 mg KOH / g, from the viewpoint of improving the flame retardancy of the polyurethane foam.

[0022] The average hydroxyl value refers to the hydroxyl value of a single polyol if only one type of polyol is used. If two or more types of polyols are used, the average hydroxyl value of the polyols is the weighted average value of the hydroxyl groups according to the blending ratio of the two or more polyols. For example, when using two types of polyols, polyol(d1) and polyol(d2), if the hydroxyl value of polyol(d1) is X1 and the mixing ratio is m1, and the hydroxyl value of polyol(d2) is X2 and the mixing ratio is m2, the average hydroxyl value is expressed by the following formula. Note that the mixing ratio is on a mass basis. Average hydroxyl value (mgKOH / g)=X1×(m1 / (m1+m2))+X2×(m2 / (m1+m2)) The hydroxyl value is a value measured in accordance with JIS K1557-1:2007.

[0023] (Polyester polyol) The polyester polyol may be a polyester polyol having an aromatic ring or an aliphatic polyester polyol, but when considering the flame retardancy of the resulting polyurethane foam, it is preferable to use a polyester polyol having an aromatic ring. The polyester polyol having an aromatic ring 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, it is preferable that the polyol includes a phthalic acid-based polyester polyol, which is a condensate of phthalic acid and glycol, and 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.

[0024] The hydroxyl value of the polyester polyol is preferably 100-500 mgKOH / g, more preferably 150-450 mgKOH / g, and even more preferably 180-400 mgKOH / g.

[0025] (Polyether polyol) Examples of polyether polyols include 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; highly functional alcohols 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.). Polyether polyols preferably have an aromatic ring. Among the above, polyether polyols produced using an initiator having an aromatic ring are polyether polyols having an aromatic ring. For example, polyether polyols produced using an aromatic amine as an initiator are polyether polyols having an aromatic ring. Among polyether polyols having an aromatic ring, tolylenediamine-based polyether polyols and Mannich-based polyether polyols can be suitably used.

[0026] Tolylenediamine-based polyether polyols are tolylenediamine-based polyether polyols manufactured using tolylenediamine as an initiator. 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.

[0027] The hydroxyl value of the polyether polyol is preferably 100 to 2000 mg KOH / g, more preferably 150 to 1000 mg KOH / g, and even more preferably 200 to 800 mg KOH / g.

[0028] <Filler> The polyol composition of the present invention contains a filler. The inclusion of a filler makes it easier to improve various properties of the polyurethane foam, such as its flame retardancy. Furthermore, while polyol compositions containing fillers are sometimes stirred before foaming, as described above, the polyol composition of the present invention, by reducing the content of low molecular weight polyhydric alcohols with a small number of carbon atoms, can suppress bumping even when stirred at high temperatures while maintaining good foamability. The filler preferably contains a flame retardant. Using a flame retardant as a filler provides high flame retardancy to the polyurethane foam. The flame retardant used as a filler is a solid flame retardant. In the present invention, using a solid flame retardant can more effectively enhance flame retardancy. A solid flame retardant is a flame retardant that becomes solid at room temperature (23°C) and atmospheric pressure (1 atm). The solid flame retardant used in the present invention is preferably at least one selected from the group consisting of phosphate-containing flame retardants, red phosphorus-based flame retardants, bromine-containing flame retardants, boron-containing flame retardants, antimony-containing flame retardants, metal hydroxides, and needle-shaped fillers.

[0029] Examples of phosphate-containing flame retardants include phosphates comprising salts of various phosphoric acids with at least one metal or compound selected from metals of groups IA to IVB of the periodic table, ammonia, aliphatic amines, aromatic amines, and heterocyclic compounds containing nitrogen in the ring. The phosphoric acid is not particularly limited, but may be monophosphates such as phosphorous acid and hypophosphorous acid, or it may be pyrophosphate, polyphosphate, etc. Examples of metals in groups IA through IVB of the periodic table include lithium, sodium, calcium, barium, iron(II), iron(III), and aluminum. Examples of aliphatic amines include methylamine, ethylamine, diethylamine, triethylamine, ethylenediamine, and piperazine. Examples of aromatic amines include aniline, o-triidine, 2,4,6-trimethylaniline, anisidine, and 3-(trifluoromethyl)aniline. Examples of heterocyclic compounds containing nitrogen in the ring include pyridine, triazine, and melamine.

[0030] Specific examples of phosphate-containing flame retardants include monophosphates such as aluminum phosphite and trialuminum phosphate, pyrophosphates, and polyphosphates. Here, the polyphosphates are not particularly limited, but examples include ammonium polyphosphate, piperazine polyphosphate, melamine polyphosphate, ammonium polyphosphate amide, and aluminum polyphosphate. One or more of the above-mentioned phosphate-containing flame retardants can be used. In the present invention, trialuminum phosphate is preferred.

[0031] Red phosphorus-based flame retardants may consist of pure red phosphorus, but they may also be red phosphorus coated with a resin, metal hydroxide, metal oxide, etc., or a mixture of red phosphorus and a resin, metal hydroxide, metal oxide, etc. The resin used to coat or mix with red phosphorus is not particularly limited, but examples include thermosetting resins such as phenolic resins, epoxy resins, unsaturated polyester resins, melamine resins, urea resins, aniline resins, and silicone resins. From the viewpoint of flame retardancy, metal hydroxides are preferred as the compound used for coating or mixing. The metal hydroxides described later may be appropriately selected and used.

[0032] Bromine-containing flame retardants are not particularly limited as long as they contain bromine in their molecular structure and are solid at room temperature and pressure, but examples include aromatic compounds containing brominated aromatic rings. Examples of brominated aromatic ring-containing aromatic compounds include monomeric organic bromine compounds such as hexabromobenzene, pentabromotoluene, hexabromobiphenyl, decabromobiphenyl, decabromodiphenyl ether, octabromodiphenyl ether, hexabromodiphenyl ether, bis(pentabromophenoxy)ethane, ethylenebis(pentabromophenyl), ethylenebis(tetrabromophthalimide), and tetrabromobisphenol A.

[0033] Furthermore, the brominated aromatic ring-containing aromatic compound may also be a brominated polymer. Specifically, examples include polycarbonate oligomers produced using brominated bisphenol A as a raw material, brominated polycarbonates such as copolymers of this polycarbonate oligomer and bisphenol A, and diexo compounds produced by the reaction of brominated bisphenol A and epichlorohydrin. In addition, examples include brominated epoxy compounds such as monoepoxy compounds obtained by the reaction of brominated phenols and epichlorohydrin, poly(brominated benzyl acrylate), brominated polyphenylene ether, brominated bisphenol A and cyanuryl chloride condensates, brominated polystyrene such as brominated (polystyrene), poly(brominated styrene), and crosslinked brominated polystyrene, and crosslinked or non-crosslinked brominated poly(methylstyrene). Furthermore, compounds other than brominated aromatic ring-containing aromatic compounds such as hexabromocyclododecane may also be used. These bromine-containing flame retardants may be used individually or in combination of two or more. Among the above, brominated aromatic ring-containing aromatic compounds are preferred, and among these, monomer-based organic bromine compounds such as hexabromobenzene are preferred.

[0034] Examples of boron-containing flame retardants used in the present invention include borax, boron oxide, boric acid, and borates. Examples of boron oxides include diboron trioxide, boron trioxide, diboron dioxide, tetraboron trioxide, and tetraboron pentoxide. Examples of borates include alkali metals, alkaline earth metals, elements from groups 4, 12, and 13 of the periodic table, and ammonium borates. Specifically, examples include alkali metal borates such as lithium borate, sodium borate, potassium borate, and cesium borate; alkaline earth metal borates such as magnesium borate, calcium borate, and barium borate; zirconium borate, zinc borate, aluminum borate, and ammonium borate. Boron-containing flame retardants may be used alone or in combination of two or more types. The boron-containing flame retardant used in the present invention is preferably a borate, and more preferably zinc borate.

[0035] Examples of antimony-containing flame retardants include antimony oxide, antimonate salts, and pyroantimonate salts. Examples of antimony oxide include antimony trioxide and antimony pentoxide. Examples of antimonate salts include sodium antimonate and potassium antimonate. Examples of pyroantimonate salts include sodium pyroantimonate and potassium pyroantimonate. Antimony-containing flame retardants may be used alone or in combination of two or more types. The preferred antimony-containing flame retardant used in this invention is antimony trioxide.

[0036] Examples of metal hydroxides used in the present invention include magnesium hydroxide, calcium hydroxide, aluminum hydroxide, iron hydroxide, nickel hydroxide, zirconium hydroxide, titanium hydroxide, zinc hydroxide, copper hydroxide, vanadium hydroxide, and tin hydroxide. A single metal hydroxide may be used, or two or more may be used in combination. A preferred metal hydroxide used in the present invention is aluminum hydroxide.

[0037] Examples of needle-shaped fillers include potassium titanate whiskers, aluminum borate whiskers, magnesium-containing whiskers, silicon-containing whiskers, silicon-based fillers, sepiolite, zonolite, elestadite, boehmite, rod-shaped hydroxyapatite, glass fibers, carbon fibers, graphite fibers, metal fibers, slag fibers, gypsum fibers, silica fibers, alumina fibers, silica-alumina fibers, zirconia fibers, boron nitride fibers, boron fibers, stainless steel fibers, and the like. These needle-shaped fillers may be used individually or in combination of two or more types.

[0038] The aspect ratio (length / diameter) of the needle-shaped filler used in the present invention is preferably in the range of 5 to 50, and more preferably in the range of 10 to 40. This aspect ratio can be determined by observing the needle-shaped filler with a scanning electron microscope and measuring its length and width.

[0039] The solid flame retardants used in the present invention may be used individually or in combination of two or more types. When using two or more types in combination, for example, two or more solid flame retardants of the same classification may be used, such as containing potassium titanate whiskers and aluminum borate whiskers as needle-shaped fillers, or one or more solid flame retardants of different classifications may be used, such as containing a red phosphorus-based flame retardant and needle-shaped fillers. The content of the solid flame retardant is not particularly limited, but is, for example, 10 to 130 parts by mass, preferably 20 to 120 parts by mass, more preferably 30 to 100 parts by mass, and even more preferably 40 to 80 parts by mass, per 100 parts by mass of polyol. By keeping the content of the solid flame retardant within the above range, it is possible to prevent the settling of the solid flame retardant without unnecessarily increasing the solid content and to improve its dispersibility.

[0040] As fillers, inorganic fillers other than the solid flame retardants mentioned above may be used. Examples of inorganic fillers other than solid flame retardants include silica, diatomaceous earth, alumina, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, calcium carbonate, magnesium carbonate, zinc carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, activated clay, sepiolite, imogolite, sericite, glass beads, silica balloons, aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon balloons, charcoal powder, various metal powders, potassium titanate, magnesium sulfate, lead zirconate titanate, aluminum borate, molybdenum sulfide, silicon carbide, various magnetic powders, fly ash, silica alumina fibers, and zirconia fibers. These inorganic fillers may be used individually or in combination of two or more types.

[0041] When the polyol composition of the present invention contains a filler, the amount is not particularly limited, but is preferably 10 to 150 parts by mass, more preferably 20 to 135 parts by mass, even more preferably 30 to 110 parts by mass, and still more preferably 40 to 90 parts by mass per 100 parts by mass of polyol. A filler content above the lower limit makes it easier to improve various properties, such as flame retardancy, of the polyurethane foam formed from the polyol composition. Furthermore, a filler content below the upper limit allows the viscosity of the polyol composition to be kept below a certain level, resulting in good handling.

[0042] <Catalyst> The polyol composition of the present invention contains a catalyst. Preferably, the catalyst is a urethane catalyst. The urethane catalyst is a catalyst that promotes the reaction between the polyol and the polyisocyanate. Preferably, the urethane catalyst contains an amino compound.

[0043] Examples of amino compounds include imidazole compounds such as 1-methylimidazole, 1,2-dimethylimidazole, 1-isobutyl-2-methylimidazole, and imidazole compounds in which the secondary amine functional group in the imidazole ring is substituted with a cyanoethyl group. Among the imidazole compounds, 1,2-dimethylimidazole is preferred. When an amino compound is included as the urethane catalyst, the content of the amino compound is preferably 2 to 14 parts by mass, more preferably 3 to 10 parts by mass, and even more preferably 3.5 to 9 parts by mass, per 100 parts by mass of polyol.

[0044] In addition to amino compounds, the urethane catalyst may also contain metal catalysts such as tin compounds and bismuth compounds, or acetylacetone metal salts. Examples of tin compounds include stannous octoate, dibutyltin diacetate, and dibutyltin dilaurate. Examples of bismuth compounds include bismuth neodecanoate and bismuth octoate.

[0045] 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.

[0046] The urethane catalyst contained in the polyol composition of the present invention may be used alone or in combination of two or more types. From the viewpoint of forming a polyurethane foam with a sufficiently high foaming ratio, the polyol composition of the present invention preferably contains an amino compound as the urethane catalyst, more preferably an imidazole compound, and even more preferably 1,2-dimethylimidazole.

[0047] The content of the urethane catalyst in the polyol composition of the present invention is preferably 1 part by mass or more, and more preferably 2 parts by mass or more, per 100 parts by mass of polyol. By setting it above the lower limit, the reaction between the polyol and polyisocyanate can be promoted at an appropriate reaction rate while maintaining good foaming properties. Furthermore, in order to improve the reaction rate and make it suitable for spray applications, the content of the urethane catalyst is more preferably 3 parts by mass or more, and even more preferably 4 parts by mass or more. In addition, from the viewpoint of obtaining foaming properties and reactivity commensurate with the catalyst content, the content of the urethane catalyst is preferably 15 parts by mass or less, more preferably 12 parts by mass or less, and even more preferably 10 parts by mass or less.

[0048] The polyol composition of the present invention may contain a trimerizing catalyst in addition to the urethane catalyst described above. The trimerizing catalyst is a catalyst that promotes trimerization, which involves the formation of isocyanurate bonds, during the reaction between the polyol composition and the polyisocyanate. This promotion of trimerization improves the flame retardancy and resistance to flame spread of the polyurethane foam. 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 formate, potassium octoate, 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 salt, and tetraphenylammonium salt can be used. Among these, quaternary ammonium salts are preferred. When quaternary ammonium salts are used, even when hydrofluoroolefin compounds such as hydrochlorofluoroolefin are used as blowing agents, catalytic activity is well maintained, allowing trimerization to proceed appropriately and improving flame retardancy. Trimerization catalysts may be used individually or in combination of two or more types.

[0049] <Phosphate esters> The polyol composition of the present invention may contain a liquid flame retardant that is liquid at room temperature (23°C) and atmospheric pressure (1 atm), specifically a phosphate ester. By using a phosphate ester, it becomes easier to improve the flame retardancy of the polyurethane foam while lowering the viscosity of the polyol composition.

[0050] As phosphate esters, monophosphate esters, condensed phosphate esters, etc., can be used. A monophosphate ester is a phosphate ester that has one phosphorus atom in its molecule. Examples of monophosphate esters include trialkyl phosphates such as trimethyl phosphate, triethyl phosphate, tributyl phosphate, and tri(2-ethylhexyl) phosphate; halogen-containing phosphate esters such as tris(β-chloropropyl) phosphate; trialkoxy phosphates such as tributoxyethyl phosphate; aromatic ring-containing phosphate esters such as tricresyl phosphate, trixylenyl phosphate, tris(isopropylphenyl) phosphate, cresyldiphenyl phosphate, and diphenyl(2-ethylhexyl) phosphate; and acidic phosphate esters such as monoisodecyl phosphate and diisodecyl phosphate.

[0051] Examples of condensed phosphate esters include aromatic condensed phosphate esters such as trialkyl polyphosphates, resorcinol polyphenyl phosphates, bisphenol A polycresyl phosphates, and bisphenol A polyphenyl phosphates. Examples of commercially available condensed phosphate esters include "CR-733S," "CR-741," and "CR747" from Daihachi Chemical Industry Co., Ltd., and "ADEKA Stab PFR" and "FP-600" from ADEKA Corporation.

[0052] The phosphate esters may be used individually from the above-mentioned types, or two or more may be used in combination. Among these, monophosphate esters are preferred from the viewpoint of making it easier to adjust the viscosity of the polyol composition and improving the flame retardancy of the polyurethane foam, and halogen-containing phosphate esters such as tris(β-chloropropyl)phosphate are more preferred. The content of phosphate ester in the polyol composition is preferably 5 to 100 parts by mass, more preferably 10 to 90 parts by mass, even more preferably 20 to 80 parts by mass, and still more preferably 30 to 70 parts by mass, per 100 parts by mass of polyol.

[0053] <Other ingredients> The polyol composition may contain other additives, such as phenolic, amine, or sulfur-based antioxidants, heat stabilizers, light stabilizers, metal damage inhibitors, antistatic agents, crosslinking agents, lubricants, softeners, pigments, dyes, and tackifying resins, to the extent that they do not interfere with the effects of the present invention.

[0054] <Manufacturing method> There are no particular limitations on the method for producing the polyol composition of the present invention. For example, it can be produced by stirring each component at room temperature using a mixer such as a homodisper for about 30 seconds to 20 minutes.

[0055] [Polyurethane resin composition, polyurethane foam] The polyurethane resin composition of the present invention comprises the above-mentioned polyol composition and a polyisocyanate. More specifically, the polyurethane resin composition is obtained by mixing at least the above-mentioned polyol composition and a polyisocyanate. The polyurethane foam is obtained by reacting and foaming the polyurethane resin composition.

[0056] <Polyisocyanate> As the polyisocyanate contained in the polyurethane resin composition of the present invention, various polyisocyanates such as aromatic, alicyclic, and aliphatic polyisocyanates having two or more isocyanate groups can be used.

[0057] Examples of aromatic polyisocyanates include phenylene diisocyanate, tolylene diisocyanate, diphenylmethane diisocyanate, dimethyldiphenylmethane diisocyanate, triphenylmethane triisocyanate, naphthalene diisocyanate, and polymethylene polyphenyl polyisocyanate (polymeric MDI).

[0058] Examples of alicyclic polyisocyanates include cyclohexylene diisocyanate, methylcyclohexylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and dimethyldicyclohexylmethane diisocyanate. Examples of aliphatic polyisocyanates include methylene diisocyanate, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, and hexamethylene diisocyanate.

[0059] Among these, aromatic polyisocyanates are preferred due to their ease of handling, rapid reaction, excellent physical properties of the resulting polyurethane foam, and low cost, and liquid diphenylmethane diisocyanate (MDI) is preferred. Examples of liquid MDI include crude MDI (also called polymeric MDI). Specific commercially available liquid MDIs 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" is a commercially available product manufactured by Nippon Polyurethane Industry Co., Ltd.) may also be used. Furthermore, a polyisocyanate may be treated by reacting some of the isocyanate active groups within it with a hydroxyl group-containing compound to increase its affinity with polyols. In addition to liquid MDI, other polyisocyanates may be used in combination, and any polyisocyanates known in the field of polyurethanes can be used without limitation.

[0060] The isocyanate index of the polyurethane resin composition of the present invention is preferably 600 or less, more preferably 550 or less, and even more preferably 500 or less. When the isocyanate index is below these upper limits, it becomes easier to improve the foaming properties during polyurethane foam formation. Furthermore, the isocyanate index of the polyurethane resin composition is preferably 90 or higher, more preferably 100 or higher, from the viewpoint of properly forming a polyurethane foam, and even more preferably 150 or higher, and even more preferably 200 or higher, from the viewpoint of promoting trimerization. The isocyanate index (INDEX) is calculated using the following method.

[0061] INDEX = Equivalents of polyisocyanate ÷ (Equivalents of polyol + Equivalents of water) × 100 Here, Equivalent weight of polyisocyanate = Number of parts of polyisocyanate 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 expressed as 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.

[0062] <Application> The polyurethane resin composition of the present invention and the polyurethane foam formed from the composition are not particularly limited in their use, but they can be used to fill cavities in structures such as buildings, furniture, automobiles, trains, and ships, or to be sprayed onto such structures. In particular, they are preferably used for spraying onto structures, i.e., for spraying, and more preferably for spraying at construction sites of buildings. Spraying can be carried out using a spraying device (e.g., GRACO A-25) and a spray gun (e.g., Gasmar D-gun). Spraying is performed by temperature-controlled mixing of the polyol composition and polyisocyanate in separate containers within the spraying device, then causing them to collide and mix at the tip of the spray gun, and finally atomizing the mixture using air pressure. The spraying device and spray gun are well-known and commercially available. Furthermore, the stock solution temperature settings and pressure can be the same as those for spraying polyurethane foam. [Examples]

[0063] The present invention will be described in more detail below using examples, but the present invention is not limited to these examples.

[0064] [Physical properties] The methods for measuring each physical property and evaluating the foam are as follows.

[0065] <Boiling point> The boiling height was measured and evaluated according to the following procedures (1) to (4). (1) The polyol composition was mixed and stirred according to the formulations shown in Table 1 so that the total amount of polyol composition was 300 g. (2) Of the polyol composition mixed and stirred in (1) above, 30g was placed into a 110ml screw-top tube (manufactured by Maruemu Co., Ltd., product name: No. 8), the opening was wrapped with sealing tape (PTFE), a stirring bar (diameter 14mm) was placed inside, and the lid was closed. (3) After immersing the contents in a 32°C bath for at least 30 minutes to maintain a constant temperature, the bottle was opened and the contents were stirred using a magnetic stirrer at 1,500 rpm. The height of the highest point after stirring was measured, and the difference from the height before stirring was calculated to determine the boiling point. (4) Based on the boiling height measured in (3) above, the boiling height was evaluated according to the following evaluation criteria. ◎: 7mm or less 〇: More than 7mm but less than 12mm △: More than 12mm but less than 17mm ×: More than 17mm

[0066] <Foaming ratio> A liquid mixture was prepared by stirring a polyol composition with the formulations listed in Table 1 and polyisocyanate (Sumika Covestro Urethane Co., Ltd., product name: Sumijoule 44V-20L) in a mass ratio of 1:1 to a total of 200g, at a liquid temperature of 10°C and 8000rpm for 3 seconds. Foam was then formed from this mixture, and the core density was measured by removing the surface skin. Based on the core density measured using the procedure described above, the foaming ratio of the polyurethane foam was evaluated. The evaluation criteria are as follows: ◎: 37kg / m 3 below ○: 37 kg / m 3 Super 40kg / m 3 below △: 40kg / m 3 Super 43kg / m 3 below ×: 43kg / m 3 super

[0067] [Materials used] The components of the polyol compositions used in each example and comparative example are as follows:

[0068] <Polyol> • p-phthalate polyester polyol (manufactured by Kawasaki Chemical Industries, Ltd., product name: Maximol RLK-087, hydroxyl value = 200 mg KOH / g)

[0069] <Filler> • Ammonium polyphosphate (manufactured by Clariant Chemicals, product name: Exolit AP422) • Melamine polyphosphate (manufactured by Nissan Chemical Corporation, product name: PHOSMEL-200) • Silicon-based needle-shaped filler (manufactured by Kinseimatic, product name: SH1250) • Red phosphorus (manufactured by Phosphorus Chemical Industry Co., Ltd., product name: Nova Excel 140) • Calcium carbonate (manufactured by Shiraishi Calcium Co., Ltd., product name: BF300) • Carbon black (manufactured by Tokai Carbon Co., Ltd., product name: Thermax)

[0070] <Liquid Flame Retardant> • Phosphate ester: Tris-β(chloropropyl) phosphate (manufactured by Daihachi Chemical Co., Ltd., product name: TMCPP)

[0071] <Foaming agent> Trans-1-chloro-3,3,3-trifluoropropene (Honeywell, product name: Solstice LBA), boiling point 18°C • Ion-exchanged water

[0072] <Catalyst> • Urethane catalyst: 1,2-dimethylimidazole (manufactured by Kao Corporation, product name: Kaolizer No. 390)

[0073] <Low molecular weight polyhydric alcohols> • Diethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.) • 1,4-Butanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) • 1,3-Propanediol (manufactured by Tokyo Chemical Industry Co., Ltd.) • Ethylene glycol (manufactured by Tokyo Chemical Industry Co., Ltd.)

[0074] [Table 1]

[0075] As is clear from the above examples, the polyol composition that satisfies the requirements of the present invention is capable of forming a polyurethane foam with a high foaming ratio, and in which bumping is suppressed even at high temperatures. In contrast, the polyol compositions prepared in the comparative examples either failed to form polyurethane foams with a high expansion ratio or failed to suppress bumping at high temperatures. More specifically, the polyol composition prepared in Comparative Example 1 did not contain low molecular weight polyhydric alcohols and therefore could not form polyurethane foams with a high expansion ratio. Furthermore, the polyol composition prepared in Comparative Example 2 contained an excess of low molecular weight polyhydric alcohols and therefore failed to suppress bumping at high temperatures.

Claims

1. A polyol composition for obtaining a polyurethane foam by reacting with a polyisocyanate, The polyol composition contains a polyol, a blowing agent, a filler, a catalyst, and a low molecular weight polyhydric alcohol having less than 6 carbon atoms. The blowing agent comprises a hydrofluoroolefin with a boiling point of 40°C or lower. The content of the low molecular weight polyhydric alcohol is less than 6% by mass on a basis of the total amount of the polyol composition. Of the low molecular weight polyhydric alcohols, the content of polyhydric alcohols with 4 or fewer carbon atoms is 2.5% by mass or more and less than 3.5% by mass on a basis of the total amount of the polyol composition. A sprayable polyol composition that does not contain polyhydric alcohols with two or fewer carbon atoms among the low molecular weight polyhydric alcohols.

2. A sprayable polyurethane resin composition comprising the sprayable polyol composition described in claim 1 and a polyisocyanate.

3. A sprayable polyurethane foam obtained by reacting and foaming the sprayable polyurethane resin composition described in claim 2.

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