JP2020035640A - Two-liquid curable resin composition for battery potting - Google Patents

Abstract

To provide a resin for battery potting, which can prevent fire from spreading between batteries despite being lightweight.SOLUTION: A two-liquid curable resin composition for battery potting contains a first component (X) and a second component (Y). The first component (X) contains a polyol (A) and water (B), the second component (Y) contains an isocyanate (C), and at least one of the first component (X) and the second component (Y) contains a flame retardant (D). The polyol (A) contains a polyol (a-1) having a molecular weight of 2,000 or more. The total quantity of the flame retardant (D) contained in the first component (X) and the second component (Y) is 25-75 pts.mass based on 100 pts.mass of the total quantity of the first component (X) and the second component (Y). The quantity of the polyol (A) is 20-150 pts.mass based on 100 pts.mass of the total quantity of the flame retardant (D).SELECTED DRAWING: None

Description

  The present invention relates to a two-part curable resin composition for battery potting.

  Japanese Patent Application Laid-Open No. 2012-28244 (Patent Document 1) discloses a technique capable of preventing a battery from burning to another battery when the battery is ignited due to an abnormality. Specifically, in Patent Literature 1, by heating a battery with a polyurethane elastomer or the like, a heat chain from a battery that has caused abnormal heat generation to another battery is suppressed.

JP 2012-28244 A

  However, in many cases, the battery pack in which the batteries are stored is required to be lightweight, so that an increase in weight due to resin potting has been a problem.

  The present invention has been made in order to solve the above problems, and an object of the present invention is to provide a two-part curable resin composition for battery potting that is light in weight and can prevent spread of fire between batteries. It is.

  In order to solve the above problems, a two-part curable resin composition for battery potting according to an aspect of the present invention is a two-part curable resin composition having a first component (X) and a second component (Y). The first component (X) includes the polyol (A) and water (B), the second component (Y) includes the isocyanate (C), and includes the first component (X) and the first component (X). At least one of the two components (Y) contains a flame retardant (D), the polyol (A) contains a polyol (a-1) having a molecular weight of 2,000 or more, and the first component (X) and the The total amount of the flame retardant (D) contained in the second component (Y) is 25 to 75 parts by mass based on 100 parts by mass of the first component (X) and the second component (Y). Yes, the amount of the polyol (A) is 10% of the total amount of the flame retardant (D). 20 to 150 parts by mass with respect to parts by mass, and the amount of the polyol (a-1) having a molecular weight of 2,000 or more is 70 to 100 parts by mass with respect to 100 parts by mass of the polyol (A); The amount of (B) is 0.35 parts by mass or less based on 100 parts by mass of the total of the first component (X) and the second component (Y).

  ADVANTAGE OF THE INVENTION According to this invention, the two-component hardening type resin composition for battery potting which can be prevented from burning between batteries while being lightweight can be provided.

  First, the contents of the embodiment of the present invention will be listed and described.

  (1) The two-pack curable resin composition for battery potting according to the present embodiment is a two-pack curable resin composition having a first component (X) and a second component (Y). The component (X) contains a polyol (A) and water (B), the second component (Y) contains an isocyanate (C), and the first component (X) and the second component (Y) At least one contains a flame retardant (D), and the polyol (A) contains a polyol (a-1) having a molecular weight of 2,000 or more, and the first component (X) and the second component (Y) The total amount of the flame retardant (D) contained in the polyol (A) is 25 to 75 parts by mass with respect to 100 parts by mass of the total amount of the first component (X) and the second component (Y). ) Is 20 to 1 with respect to 100 parts by mass of the total amount of the flame retardant (D). 0 parts by mass, the amount of the polyol (a-1) having a molecular weight of 2,000 or more is 70 to 100 parts by mass with respect to 100 parts by mass of the polyol (A), and the amount of the water (B) is 0.35 parts by mass or less based on 100 parts by mass of the total amount of the first component (X) and the second component (Y).

  According to such a configuration, the battery can be potted with the urethane foam, so that the entire battery pack can be reduced in weight and a high anti-spreading property can be provided between batteries (cells). Further, it is possible to suppress deformation and reduction in strength due to shrinkage of urethane foam, which usually occur when a large amount of a flame retardant is contained. In addition, it is possible to suppress the influence of heat generated during curing on the battery life and the like.

  (2) Preferably, the polyol (a-1) having a molecular weight of 2,000 or more includes a polyether polyol (a-1-1) having a structure in which a plurality of oxyethylene groups are bonded in series at each terminal, The total amount of the oxyethylene groups connected in series at each terminal is 5 to 35 mol% of the whole polyether polyol (a-1-1).

  With such a configuration, shrinkage of the urethane foam can be further suppressed.

  (3) Preferably, the isocyanate (C) contains a urethane prepolymer (c-1) having an isocyanate group at a terminal, and the urethane prepolymer reacts at least an aromatic isocyanate with a polyol (cp). To be obtained.

  With such a configuration, shrinkage of the urethane foam can be further suppressed.

  (4) More preferably, the aromatic isocyanate is at least one of diphenylmethane diisocyanate and a modified diphenylmethane diisocyanate.

  With such a configuration, shrinkage of the urethane foam can be further suppressed.

  (5) Preferably, the isocyanate (C) includes a urethane prepolymer (c-1) having an isocyanate group at a terminal, and the urethane prepolymer (c-1) contains at least an isocyanate (ci); Obtained by reacting with castor oil-based polyol.

  With such a configuration, the waterproofness of the urethane foam can be improved.

  (6) Preferably, the polyol (A) further contains a polyol (a-2) having a molecular weight of 200 or less, and the amount of the polyol (a-2) having a molecular weight of 200 or less is determined by the amount of the flame retardant (D ) Is 1.5 to 15 parts by mass with respect to 100 parts by mass in total.

  With such a configuration, even when the battery explosively ignites, the urethane foam can effectively prevent the adjacent battery from burning, and the battery pack appropriately absorbs an external impact. Can be as hard as possible.

  (7) The urethane foam according to the present embodiment is a cured product of the two-part curable resin composition for battery potting.

  (8) The battery pack according to the present embodiment is potted with the urethane foam.

  Hereinafter, embodiments of the present invention will be described more specifically.

  The two-part curable resin composition for battery potting according to the present embodiment (hereinafter, also simply referred to as “two-part curable resin composition”) includes at least a first component (X) and a second component (X) described below. It has a component (Y). The two-component curable resin composition may have a component other than the first component (X) and the second component (Y).

(First component (X))
The first component (X) according to the present embodiment contains a polyol (A), water (B), and a flame retardant (D). The flame retardant (D) may be contained in the second component (Y) instead of the first component (X), or may be contained in both the first component (X) and the second component (Y). Is also good.

(Polyol (A))
The polyol (A) according to the present embodiment contains a polyol (a-1) having a molecular weight of 2000 or more. The molecular weight of the polyol (a-1) is preferably 2500 or more from the viewpoint of suppressing the shrinkage of the obtained urethane foam. Further, from the viewpoint of enhancing the anti-fire property between batteries by ensuring that the foaming resin penetrates into a gap between a plurality of batteries, the molecular weight is preferably 10,000 or less, and is preferably 6,000 or less. More preferably, it is 5,000 or less, more preferably, 4,000 or less. When the urethane foam shrinks, a gap is formed between the battery and the urethane foam, resulting in a decrease in anti-spreading properties, or a decrease in strength, and the battery cannot withstand an impact when explosively ignited. I do. Further, when the urethane foam shrinks, for example, the wall surface of the container filled with the urethane foam is pulled inward to apply stress, and the container may be deformed or cracked.

  The polyol (a-1) having a molecular weight of 2,000 or more is not particularly limited, and examples thereof include a polyether polyol, a polyester polyol, and a polyolefin polyol.

  Examples of the polyether polyol include, but are not particularly limited to, propylene glycol, ethylene glycol, glycerin, trimethylolpropane, hexanetriol, triethanolamine, diglycerin, pentaerythritol, ethylenediamine, methyldigit, aromatic diamine, sorbitol, and sucrose. And those obtained by ring-opening polymerization of an alkylene oxide using, phosphoric acid or the like as an initiator.

  The polyether polyol is not particularly limited, but may also include a polymer polyol obtained by polymerizing a vinyl monomer such as acrylonitrile or styrene in the polyether polyol and dispersing the resulting polymer in the polyether polyol. That is, the polymer polyol is a polyether polyol in which resin particles are dispersed. The average particle size of the resin is not particularly limited, but is about 0.1 to 10 μm.

  The polyester polyol is not particularly limited, but includes a polyhydric hydroxyl group-containing compound, a polycarboxylic acid (aromatic polycarboxylic acid and aliphatic polycarboxylic acid) or an anhydride and a lower alkyl (the alkyl group has 1 to 4 carbon atoms). Polycondensation reaction products with ester-forming derivatives such as esters (such as phthalic anhydride and dimethyl terephthalate); polylactone polyols; polycarbonate polyols; and castor oil derivatives [castor oil fatty acid and polyhydric alcohol or polyoxyalkylene polyol Polyester polyols (mono- or diglycerides of castor oil fatty acids, mono-, di- or triesters of castor oil fatty acids and trimethylolpropane, mono- or diesters of castor oil fatty acids and polyoxypropylene glycol, etc.); Al It can be used like castor oil and the like derived hydroxyl terminated prepolymer and a diphenylmethane diisocyanate]; alkylene oxide obtained by adding the (two to four carbons).

  Examples of the polyolefin polyol include, but are not particularly limited to, polybutadiene polyol, polyisoprene polyol, and hydrogenated products thereof.

  The polyol (a-1) is preferably a polyether polyol from the viewpoint of suppressing shrinkage of the obtained urethane foam.

  The polyol (a-1) may contain a plurality of polyols of different types, or may contain a plurality of polyols of the same type but having different molecular weight distributions.

In the present disclosure, “molecular weight” represents a number average molecular weight of a compound having a molecular weight distribution such as polypropylene glycol.

  The amount of the polyol (a-1) having a molecular weight of 2,000 or more is 70 to 100 parts by mass, when the total amount of the polyol (A) is 100 parts by mass. If the polyol (a-1) is less than this range, the obtained urethane foam will shrink.

  The polyol (a-1) having a molecular weight of 2,000 or more preferably contains a polyether polyol (a-1-1) having a structure in which an ethylene oxide is block-added to a terminal portion. Specifically, each terminal of the polyether polyol (a-1-1) has a structure in which a plurality of ethylene oxides are continuously polymerized. That is, the polyether polyol (a-1-1) has a structure in which a plurality of oxyethylene groups are connected in series at each terminal.

  In addition, the polyether polyol (a-1-1) is preferably bifunctional or trifunctional from the viewpoint of enhancing impact absorption.

An example of such a polyether polyol (a-1-1) can be represented, for example, by the following formula (1).
(EO) _a- (AO) _b -R-[(AO) _c- (EO) _d ] _x (1)

  In the formula (1), R represents a structure derived from a starting material or a structure in which a starting material alkylene oxide is polymerized, AO represents an oxyalkylene group other than an oxyethylene group, and EO represents an oxyethylene group. a and d indicate the number of repeating units of the corresponding EO, respectively, and b and c indicate the number of repeating units of the corresponding AO. x is either 1 or 2. The polyether polyol of the formula (1) is bifunctional when x = 1 and trifunctional when x = 2. That is, the polyether polyol of the formula (1) has two terminals when x = 1, and has three terminals when x = 2.

In addition, the total amount of oxyethylene groups connected in series at each end (for example, the total amount of “(EO) _a ” and “(EO) _d ” in the formula (1)) indicates that irregularities are formed on the urethane foam surface. From the viewpoint of adjusting the appearance of the urethane foam, for example, not to cause it, it is preferably at least 5 mol% of the entire polyether polyol (a-1-1) (for example, the entire structure represented by the formula (1)), and preferably 10 mol%. More preferably, it is the above. In addition, from the viewpoint of suppressing shrinkage of the urethane foam, the total amount is preferably 35 mol% or less, and more preferably 30 mol% or less.

  The polyol (a-1) having a molecular weight of 2,000 or more may contain a polyol (a-1-2) having a molecular weight of 2,000 or more, in addition to the polyether polyol (a-1-1).

  Further, the polyol (A) according to the present embodiment preferably further contains a polyol (a-2) having a molecular weight of 200 or less from the viewpoint of suppressing shrinkage of the obtained urethane foam.

  The polyol (a-2) having a molecular weight of 200 or less is not particularly limited, but ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, 3-methyl-1,5-pentanediol, 2-butyl Aliphatic diols such as -2-ethyl-1,3-propanediol and 2-methyl-1,3-propanediol; alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol Glycerin, trimethylolpropane, pentae It may be mentioned tri- or higher functional hydroxyl group-containing compounds such as Suritoru.

  As the polyol (a-2), ethylene glycol and diethylene glycol are preferred from the viewpoint of suppressing shrinkage of the urethane foam.

  Further, the polyol (A) according to the present embodiment may include a polyol other than the polyol (a-1) having a molecular weight of 2,000 or more and the polyol (a-2) having a molecular weight of 200 or less. Examples of such other polyols include castor oil-based polyols, polyether polyols, polyester polyols, and polyolefin polyols.

  The amount of the polyol (A) according to the present embodiment is 20 to 150 parts by mass based on 100 parts by mass of the total amount of the flame retardant (D) contained in the first component (X) and the second component (Y). And preferably 35 to 120 parts by mass, more preferably 40 to 90 parts by mass. If the polyol (A) according to the present embodiment is less than this range, the obtained urethane foam shrinks. On the other hand, when the amount of the polyol (A) is larger than this range, it is not possible to give the foamed urethane a sufficient anti-combustibility.

  In addition, the amount of the polyol (a-2) having a molecular weight of 200 or less according to the present embodiment is preferably 1.5 to 1.5 parts by mass based on 100 parts by mass of the total amount of the flame retardant (D) from the viewpoint of improving the anti-combustion property. The amount is preferably 15 parts by mass, more preferably 1.7 to 12 parts by mass.

(Water (B))
The first component (X) according to the present embodiment contains water (B). The amount of water (B) is 0 with respect to 100 parts by mass of the total amount of the first component (X) and the second component (Y) from the viewpoint of suppressing the variation in the expansion ratio while realizing the weight reduction of the urethane foam. 0.1 part by mass or more, more preferably 0.15 part by mass or more. When the foaming ratio varies, the urethane foam does not spread evenly in the battery pack, so that the fire preventing property is reduced, or the urethane foam exceeds the capacity of the battery pack.

  Further, the amount of water (B) is 0.35 parts by mass or less based on 100 parts by mass of the total amount of the first component (X) and the second component (Y) from the viewpoint of suppressing shrinkage of the urethane foam. And more preferably 0.3 parts by mass or less.

(Flame retardant (D))
The total amount of the flame retardant (D) contained in at least one of the first component (X) and the second component (Y) according to the present embodiment is the first component (X) and the second component (Y) Is 25 to 75 parts by mass, preferably 29 to 72 parts by mass with respect to 100 parts by mass of the total amount of If the amount of the flame retardant (D) is less than this range, the foamed urethane cannot have sufficient anti-burning properties. If the amount of the flame retardant (D) is larger than this range, the resin shrinks.

  The flame retardant (D) according to the present embodiment is not particularly limited, but examples thereof include a bromine-based flame retardant, a phosphorus-based flame retardant, a nitrogen-based flame retardant, and an inorganic flame retardant. As the flame retardant (D), one kind of flame retardant may be used alone, or two or more kinds of flame retardants may be used in combination.

  Examples of the brominated flame retardant include, but are not particularly limited to, hexabromocycloheptane, tetrabromocycloheptane, tetrabromocyclooctane, hexabromocyclododecane, other brominated cycloalkanes, polybromodiphenyl ether, and tetrabromobisphenol A (hereinafter, referred to as tetrabromobisphenol A). TBBA), TBBA / epoxy oligomer, TBBA / carbonate oligomer, TBBA / bis (dibromopropyl ether), TBBA / bis (dibromomethylpropyl ether), other TBBA derivatives, bis (pentabromophenyl) ethane, 1,2-bis (2,4,6-trisbromophenoxy) ethane, 1,2-bis (2,4,6-trisbromophenoxy) -1,3,5-triazine, 2,6-dibromomonophenol, 2,4- Dibromomono Phenol, ethylene bistetrabromophthalimide, tribromophenyl allyl ether, tribromophenyl acrylate, pentabromobenzyl allyl ether, pentabromobenzyl acrylate, bromoacrylate monomer, brominated polystyrene, polybrominated styrene, hexabromobenzene, 2,4 And methylol compounds of -diamino-6- (3,3,3-tribromo-1-propyl) -1,3,5-triazine, tris (tribromoneopentyl) phosphate and the like.

  Examples of the phosphorus-based flame retardant include, but are not particularly limited to, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, cresyl phenyl phosphate, other aromatic phosphate esters, aromatic condensed phosphate esters, and diphenyl monophosphate phosphate. Orthoxenyl, 2-naphthyldiphenyl phosphate, 10-benzyl-9,10-dihydroxy-9-oxa-10-phosphaphenanthrene-10-oxide, triphenylphosphine oxide, 5,5-dimethyl-2- (2 ′ -Phenylphenoxy) -1,3,2-dioxaphosphorinane-2-oxide, tris (chloropropyl) phosphate, tris (dichloropropyl) phosphate and the like.

  Examples of the nitrogen-based flame retardant include, but are not particularly limited to, guanidine compounds, guanylurea compounds (eg, guanylurea phosphate), melamine compounds (eg, polymelamine phosphate, melamine sulfate, melamine cyanurate) and polyphosphorus. Acid ammonium salts and the like.

  Examples of the inorganic flame retardant include, but are not particularly limited to, antimony trioxide, antimony pentoxide, magnesium hydroxide, and aluminum hydroxide.

  As the flame retardant (D) according to the present embodiment, a phosphorus-based flame retardant is preferable from the viewpoint of enhancing the anti-burning property of urethane foam by uniformly dispersing the flame retardant, and trixylenyl phosphate and tricresyl phosphate are preferable. More preferred.

(2nd component)
The second component (Y) according to the present embodiment contains isocyanate (C). Examples of the isocyanate (C) include an aliphatic isocyanate, an alicyclic isocyanate, an aromatic isocyanate, and an araliphatic isocyanate.

  Examples of the aliphatic isocyanate include tetramethylene diisocyanate, dodecamethylene diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1,2 Examples thereof include 5-diisocyanate and 3-methylpentane-1,5-diisocyanate.

  Examples of the alicyclic isocyanate include isophorone diisocyanate, hydrogenated xylylene diisocyanate, 4,4′-dicyclohexylmethane diisocyanate, 1,4-cyclohexane diisocyanate, methylcyclohexylene diisocyanate, and 1,3-bis (isocyanatomethyl) cyclohexane. be able to.

  As the aromatic isocyanate, tolylene diisocyanate, diphenylmethane diisocyanate (MDI) polymethylene polyphenyl polyisocyanate, 4,4′-dibenzyl diisocyanate, 1,5-naphthylene diisocyanate, xylylene diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate and the like can be mentioned. Note that MDI has three types of isomers, 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, and 4,4'-diphenylmethane diisocyanate.

  Examples of the aromatic aliphatic isocyanate include dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, α, α, α, α-tetramethylxylylene diisocyanate.

  Further, as the isocyanate (C), for example, modified products such as carbodiimide modified product, allophanate modified product, buret modified product, isocyanurate modified product and adduct modified product of these isocyanates can be used.

  The isocyanate (C) according to the present embodiment preferably contains a urethane prepolymer (c-1) having an isocyanate group at the terminal. The urethane prepolymer (c-1) is obtained, for example, by reacting a polyol (cp) with an isocyanate (ci) under conditions such that the number of isocyanate groups is excessive relative to the number of hydroxyl groups.

  The isocyanate (ci) used for producing the urethane prepolymer (c-1) is not particularly limited, and examples thereof include the above-mentioned aliphatic isocyanate, alicyclic isocyanate, aromatic isocyanate, and araliphatic isocyanate. .

  As the isocyanate (ci), from the viewpoint of suppressing shrinkage of urethane foam, aromatic isocyanate is preferable, and MDI and a modified MDI are more preferable. Examples of the modified MDI include, but are not particularly limited to, a polymer, a urea, an allophanate, a biuret, a carbodiimide, a uretonimine, a uretdione, and an isocyanurate. As the modified MDI, a carbodiimide modified is preferable.

  The polyol (cp) is not particularly limited, and examples thereof include castor oil-based polyol, polyether polyol, low molecular weight glycol, polyester polyol, and polyolefin polyol.

  As the polyol (cp), a castor oil-based polyol is preferable from the viewpoint of enhancing the waterproofness of the urethane foam. If the waterproofness of the urethane foam is high, a waterproof function can be imparted to the entire battery pack, so that the battery pack can be appropriately protected from water drops and the like.

  The castor oil-based polyol is not particularly limited, but castor oil, hydrogenated castor oil, transesterified castor oil and other fats and oils, reaction product of castor oil and polyhydric alcohol, castor oil fatty acid and polyhydric alcohol, And those obtained by addition-polymerizing an alkylene oxide thereto.

  For this reason, the urethane prepolymer (c-1) according to the present embodiment is particularly preferably obtained by reacting an aromatic isocyanate with a castor oil-based polyol.

  In the two-part curable resin composition according to the present embodiment, the molar ratio (NCO / OH) between the isocyanate groups and the hydroxyl groups is preferably 0.6 to 1.5, and 0.7 to 1.3. Is more preferable. By setting the molar ratio of the isocyanate group to the hydroxyl group in such a range, the shrinkage of the obtained urethane foam can be suppressed.

  The two-part curable resin composition according to the present embodiment includes, for example, a catalyst, a foam stabilizer (for example, a silicone foaming agent such as a polyalkylsiloxane-polyoxyalkylene block copolymer), a surfactant, and an antioxidant. Well-known additives such as antifungal agents, deodorants, dispersants, discoloration inhibitors, plasticizers, and fragrances may be contained within a range that does not impair the object of the present invention.

(Cured product)
When the first component (X) and the second component (Y) are mixed, the two-component curable resin composition according to the present embodiment cures while foaming to form urethane foam. In general, when heat is applied to a battery, the life of the battery may be affected. However, in the two-component curable resin composition, the reaction heat at the time of curing is suppressed to a low level, so that the risk is small. The heat generation temperature when the two-part curable resin composition is cured is preferably 80 ° C. or lower, more preferably 70 ° C. or lower.

Further, the density of urethane foam as a potting material for a battery is preferably 0.7 g / cm ³ or less, more preferably 0.5 g / cm ³ or less, from the viewpoint of reducing the weight of the battery pack. By potting with such urethane foam, it is possible to achieve a sufficient reduction in weight as compared with a urethane elastomer which is usually 1 g / cm ³ or more.

  The hardness (Shore C) of urethane foam as a potting material for a battery is preferably 10 to 60. This can reduce the damage to the battery due to the stress at the time of curing the resin, and can appropriately absorb the external impact of the battery pack.

  The thermal conductivity of urethane foam as a potting material for a battery is preferably 0.05 to 0.20 (W / (m · K)). Thus, even when the battery is ignited, it is possible to effectively prevent the adjacent battery from burning, and to release the heat generated in the battery to some extent because the thermal conductivity is not too low.

(Battery pack)
The two-part curable resin composition according to the present embodiment is used for potting a battery. Specifically, after mixing the first component (X) and the second component (Y), the mixture is poured into a case or the like in which a battery is housed, thereby forming a foamed product that is a cured product of the two-component curable resin composition. A battery pack potted with urethane can be obtained.

  Here, the function of the two-component curable resin composition for preventing burning between batteries is particularly effectively exerted, for example, when two or more batteries (cells) are present in a battery pack. Further, it is preferable that the batteries in the battery pack are not arranged in a state of being in contact with each other, but are arranged via the urethane foam according to the present embodiment. In the battery pack, a case or the like for accommodating the battery is not always necessary, and the urethane foam potting the battery may be exposed.

  In addition, for example, even when the composition corresponding to the first component (X) and the composition corresponding to the second component (Y) are separately distributed on the market, the composition corresponding to the first component (X) It should be understood that the use of the composition for mixing and the composition corresponding to the second component (Y) for potting of a battery is equivalent to the practice of the present invention.

  Further, for example, each component to be contained in the first component (X) (or the second component (Y)) may be sold separately or the like. Therefore, it should be understood that if a material equivalent to the above urethane foam is formed, the invention relating to the urethane foam corresponds to the embodiment.

  For example, even when the first component (X) does not contain water (B), a predetermined amount of water (B) is separately added when mixing the first component (X) and the second component (Y). By adding, the effect of the present invention can be obtained. However, such actions should be taken as the practice of the urethane foam according to the invention, since the resulting urethane foam is equivalent to the case where the first component (X) contains water (B).

  Hereinafter, the present invention will be described more specifically with reference to Examples, but the present invention is not limited to the following Examples. Hereinafter, “parts” or “%” is based on mass unless otherwise specified.

Table 1 shows, for Examples 1 to 10 and Comparative Examples 1 to 5, types and amounts (parts by mass) of raw materials to be mixed with the first component (X) and the second component (Y), various ratios, and the like. And the results of the evaluation described below. Here, the various ratios and the like are specifically the following (1) to (6).
(1) The total amount of the flame retardant (D) based on 100 parts by mass of the total amount of the first component (X) and the second component (Y) ((D) / ((X) + (Y)) × 100)

(2) Amount of polyol (A) based on 100 parts by mass of total amount of flame retardant (D) ((A) / (D) × 100)

(3) Amount of polyol (a-1) having a molecular weight of 2000 or more based on 100 parts by mass of polyol (A) (a-1) / (A) × 100

(4) The amount of water (B) based on 100 parts by mass of the total of the first component (X) and the second component (Y) ((B) / ((X) + (Y)) × 100)

(5) (a-1-1) Total (mol%) of oxyethylene groups at each terminal of polyether polyol

(6) Amount of polyol (a-2) having a molecular weight of 200 or less based on 100 parts by mass of total amount of flame retardant (D) (a-2) / (D) × 100

  First, an isocyanate group-terminated urethane prepolymer (c-1-1) used as a urethane prepolymer (c-1) having an isocyanate group at the terminal was prepared as follows. That is, castor oil was added to 1700 parts by mass of carbodiimide-modified MDI (Lupranate MM-103, manufactured by BASF INOAC Polyurethane Co., Ltd.) previously charged in a 1-liter 4-neck round bottom flask equipped with a nitrogen inlet tube, a cooling condenser, a thermometer, and a stirrer. 300 parts by mass of (castor oil D manufactured by Ito Oil Co., Ltd.) was divided and charged. Then, the reaction was carried out at 60 ° C. for 8 hours under a nitrogen stream. As a result, (c-1-1) isocyanate group-terminated urethane prepolymer having 23.3% by mass of free isocyanate groups and 15% by mass of a component derived from castor oil in the urethane prepolymer was obtained.

Next, details of each of the other raw materials described in Table 1 will be described.
<First component>
[Polyol having a molecular weight of 2000 or more (a-1)]
(A-1-1) Polyether polyol Exenol 230 manufactured by AGC
-Molecular weight: 3000
-At each end, a plurality of oxyethylene groups are connected in series.
-Total amount of oxyethylene groups at each terminal: 24 mol%

(A-1-2) Polyether polyol Exenol 923 manufactured by AGC
-Molecular weight: 5000

[Polyol (a-2) having a molecular weight of 200 or less]
(A-2-1) Ethylene glycol manufactured by Mitsubishi Chemical Corporation ・ Molecular weight: 62.07

(A-2-2) Diethylene glycol manufactured by Mitsubishi Chemical Corporation ・ Molecular weight: 106.12

[catalyst]
(E-1) Triethylenediamine (catalyst 1)
Tosoh TEDA L-33

(E-2) bis (2-dimethylaminoethyl) ether (catalyst 2)
TOYOCAT ET manufactured by Tosoh Corporation

[Flame retardant (D)]
(D-1) trixylenyl phosphate (TXP),
Daihachi Chemical Industry Co., Ltd.

(D-2) tricresyl phosphate (TCP),
Daihachi Chemical Industry Co., Ltd.

<Second component>
[Isocyanate (C)]
(C-2-1) Polymeric MDI
Millionate MR-200 manufactured by Tosoh Corporation

(Preparation of the first and second components)
According to the mixing ratio (parts by mass) shown in Table 1, the first component (X) and the second component (Y) of each example are prepared.

[Evaluation]
(density)
After mixing the first component (X) and the second component (Y) adjusted to 23 ° C. with a homodisper for 10 seconds, the mixture is allowed to stand for 24 hours in an environment of a temperature of 23 ° C. and a humidity of 50% to form a foam to be evaluated. Urethane is obtained. Thereafter, the density (g / cm ³ ) of the urethane foam was measured in accordance with JIS K-7222: 2005. Specifically, the core portion of the urethane foam was cut out to have a size of 50 mm × 50 mm × 50 mm to obtain a test piece, and the obtained test piece was measured.

(hardness)
After mixing the first component (X) and the second component (Y) adjusted to 23 ° C. with a homodisper for 10 seconds, the mixture is allowed to stand for 24 hours in an environment of a temperature of 23 ° C. and a humidity of 50% to form a foam to be evaluated. Urethane is obtained. Thereafter, the hardness of the urethane foam was measured in accordance with JIS K-7312: 1996. Specifically, the core of urethane foam was cut out to a size of 50 mm x 50 mm x 50 mm to obtain a test piece, and the obtained test piece was measured using an Asker C hardness tester manufactured by Kobunshi Keiki Co., Ltd.

(Thermal conductivity)
After mixing the first component (X) and the second component (Y) adjusted to 23 ° C. with a homodisper for 10 seconds, the mixture is allowed to stand for 24 hours in an environment of a temperature of 23 ° C. and a humidity of 50% to form a foam to be evaluated. Urethane is obtained. Thereafter, a 60 mm × 120 mm × 10 mm plate-shaped test piece is cut out from the urethane foam, and the heat conductivity (W / (W / ( m · K)).

(Non-shrinkable)
The first component (X) and the second component (Y) adjusted to 23 ° C. are mixed by a homodisper for 10 seconds, and 100 g of the mixture is poured into a cylindrical polypropylene container having a bottom area of 38 cm ² , and the temperature is 23 ° C., the humidity is 23 ° C. It was allowed to stand for 24 hours in an environment of 50% to obtain urethane foam to be evaluated. Thereafter, the polypropylene container was removed, and whether or not the urethane foam was contracted was visually checked. Specifically, when the urethane foam is contracted, for example, the side surface of the urethane foam is inwardly distorted. The non-shrinkage of the urethane foam, that is, whether or not the shrinkage of the urethane foam was suppressed, was evaluated based on the following criteria.
〇: Shrinkage cannot be confirmed.
×: Shrinkage can be confirmed.

(Exothermic temperature)
The first component (X) and the second component (Y) adjusted to 23 ° C. were mixed by a homodisper for 10 seconds, and 100 g of the mixture was poured into a cylindrical polypropylene container having a bottom area of 38 cm ² . Under an environment of a temperature of 23 ° C. and a humidity of 50%, the reaction temperature at the center of the resin composition during curing was measured using a thermocouple. The highest value among the measured values that change with time was defined as the exothermic temperature (° C.) according to this evaluation.

(Anti-fire prevention)
(Preparation of battery pack for test)
Three cylindrical battery cells (NCR18650B manufactured by Panasonic) are placed in a container having an inner dimension of 22 × 85 × 68 mm in height such that the gap between adjacent battery cells is 2 mm and the axial direction is parallel. So that they were arranged in the vertical direction and fixed (both ends of the battery cells were fixed). Each battery cell has a capacity of 3 Ah and a weight of 46 g. Each battery was fully charged. The first component (X) and the second component (Y) adjusted to 23 ° C. are mixed by a homodisper for 10 seconds, poured into the above container, and allowed to stand at 23 ° C. and 50% humidity for 24 hours. did. Thereby, the urethane foam entered between the batteries, and a battery pack in a state of covering each battery was prepared.
(Nail test)
One of the three battery cells of the battery pack was nailed with a nail to ignite the battery cell. Then, it was confirmed whether or not the battery cell adjacent to the upper side or the lower side would burn, that is, whether or not any of the adjacent battery cells would ignite. The nail has a length of 45 mm and a thickness of 2.45 mm. The speed of the nail when piercing it was 30 mm / sec, and the depth of the piercing nail was 18 mm from the surface of the battery cell. The anti-burning properties of the urethane foam were evaluated based on the following criteria.
〇: The adjacent battery cells did not burn x: The adjacent battery cells burned

With reference to the evaluation results described in Table 1, it was confirmed that the urethane foams of Examples 1 to 10 did not shrink and had the anti-burning property at least. In addition, since the shrinkage was confirmed about the urethane foams of Comparative Examples 1, 3, and 4, other tests were not performed. In each example and each comparative example, the same catalyst was used in order to make the conditions as uniform as possible. However, the technical range of the two-part curable resin composition according to the present invention is limited by the type of the catalyst and the presence or absence of the catalyst. Not done. The blending of other components may be prepared for convenience, but this does not limit the technical scope of the two-part curable resin composition according to the present invention.

Claims (8)

A two-part curable resin composition having a first component (X) and a second component (Y),
The first component (X) includes a polyol (A) and water (B),
The second component (Y) contains an isocyanate (C),
At least one of the first component (X) and the second component (Y) contains a flame retardant (D),
The polyol (A) contains a polyol (a-1) having a molecular weight of 2,000 or more,
The total amount of the flame retardant (D) contained in the first component (X) and the second component (Y) is 100 parts by mass as the total amount of the first component (X) and the second component (Y). 25 to 75 parts by mass with respect to
The amount of the polyol (A) is 20 to 150 parts by mass based on 100 parts by mass of the total amount of the flame retardant (D),
The amount of the polyol (a-1) having a molecular weight of 2,000 or more is 70 to 100 parts by mass relative to 100 parts by mass of the polyol (A).
The amount of the water (B) is 0.35 parts by mass or less based on 100 parts by mass of the total of the first component (X) and the second component (Y). .   The polyol (a-1) having a molecular weight of 2,000 or more includes a polyether polyol (a-1-1) having a structure in which a plurality of oxyethylene groups are bonded in series at each terminal, and the polyol (a-1) has a structure in which the series is bonded at each terminal. 2. The two-part curable resin composition for battery potting according to claim 1, wherein the total amount of oxyethylene groups bonded to the polyether polyol (a-1-1) is 5 to 35 mol%. The isocyanate (C) includes a urethane prepolymer (c-1) having an isocyanate group at a terminal,
The two-part curable resin composition for battery potting according to claim 1 or 2, wherein the urethane prepolymer (c-1) is obtained by reacting at least an aromatic isocyanate and a polyol (cp).   The two-part curable resin composition for battery potting according to claim 3, wherein the aromatic isocyanate is at least one of diphenylmethane diisocyanate and a modified diphenylmethane diisocyanate. The isocyanate (C) includes a urethane prepolymer (c-1) having an isocyanate group at a terminal,
The two-package for battery potting according to any one of claims 1 to 4, wherein the urethane prepolymer (c-1) is obtained by reacting at least an isocyanate (ci) with a castor oil-based polyol. Curable resin composition. The polyol (A) further contains a polyol (a-2) having a molecular weight of 200 or less,
The amount of the polyol (a-2) having a molecular weight of 200 or less is 1.5 to 15 parts by mass with respect to 100 parts by mass of the total amount of the flame retardant (D). Item 2. A two-part curable resin composition for battery potting according to item 1.   A urethane foam which is a cured product of the two-part curable resin composition for battery potting according to any one of claims 1 to 6. A battery pack potted with the urethane foam according to claim 7.