Curable vibration-damping composition and vibration-damping material

Abstract

To provide a curable vibration-damping composition capable of forming a vibration-damping material exhibiting excellent vibration-damping properties in a room temperature (0-35°C) environment, and to provide a vibration-damping material obtained by curing the curable vibration-damping composition.SOLUTION: The curable vibration-damping composition according to the present invention includes at least two or more selected from the group consisting of castor oil-based polyols (A), castor oil-based polyols (B), castor oil-based polyols (C), castor oil-based polyols (D), and castor oil-based polyols (E), the castor oil-based polyols having a weighted average of hydroxyl values of 150-300 mgKOH / g, and an isocyanate compound.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a curable vibration-damping composition and a vibration-damping material. [Background technology]

[0002] Conventionally, to reduce noise caused by solid vibration, damping materials have been used in industrial machinery, automobiles, home appliances, etc. Asphalt sheets have been widely used as damping materials, but in consideration of cost benefits such as labor savings, coated damping materials have been proposed that can be applied to the surface of the damped object.

[0003] Acrylic emulsion type damping materials have been proposed as coating-type damping materials, but they require a drying process, and have the problem that if the thickness of the damping material is increased to ensure vibration-damping properties, the damping material will bulge.

[0004] Therefore, Patent Document 1 proposes a resin composition for vibration damping materials, which comprises a polyol-containing component (A) and a polyisocyanate (B), wherein the polyol-containing component (A) contains castor oil (A1), and when the composition is cured, the Tan δ peak top is 0.7 or more, and the temperature at the peak top is in the range of -10°C or more and 100°C or less. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2019-534920 Summary of the Invention [Problem to be solved by the invention]

[0006] The performance of a vibration-damping material is evaluated using the loss factor tanδ, and it is considered preferable that the peak of tanδ is located at the desired temperature at which performance is desired to be exhibited. It is also considered that the higher the peak height of tanδ, the better the vibration-damping performance, and it is considered preferable that the temperature range over which tanδ is 0.3 or more is wide.

[0007] The tan δ of the vibration damping materials obtained by curing the compositions specifically disclosed in Patent Document 1 all reach their maximum capacity at 50°C or higher, and therefore have the problem that they are not suitable for general use in which use is expected in a room temperature environment.

[0008] Furthermore, the composition of Patent Document 1 adjusts the tan δ peak position of a single castor oil by using a low molecular weight crosslinking agent. As the crosslinking increases with the low molecular weight crosslinking agent, the tan δ peak height decreases and the temperature range in which tan δ is 0.3 or greater narrows, resulting in another problem of reduced vibration damping properties of the vibration damping material.

[0009] The present invention provides a curable vibration-damping composition capable of producing a vibration-damping material that exhibits excellent vibration-damping properties in a room temperature (0 to 35°C) environment, and a vibration-damping material obtained by curing this curable vibration-damping composition. [Means for solving the problem]

[0010] The curable vibration-damping composition of the present invention comprises: a castor oil-based polyol containing at least two or more selected from the group consisting of: a castor oil-based polyol (A) having a hydroxyl value of 200 to 320 mgKOH / g and an average functionality of 2 or more but less than 3; a castor oil-based polyol (B) having a hydroxyl value of 100 to 199 mgKOH / g and an average functionality of less than 3; a castor oil-based polyol (C) having a hydroxyl value of 50 to 99 mgKOH / g and an average functionality of 2 or more but less than 3; a castor oil-based polyol (D) having a hydroxyl value of 49 mgKOH / g or less and an average functionality of 2 or more but less than 3; and a castor oil-based polyol (E) having a hydroxyl value of 200 to 400 mgKOH / g and an average functionality of 3 or more but less than 6, and having a weighted average hydroxyl value of 150 to 300 mgKOH / g; and an isocyanate compound.

[0011] The vibration-damping material of the present invention is characterized by being a cured product of a curable vibration-damping composition. [Effects of the Invention]

[0012] The curable vibration-damping composition of the present invention contains a castor oil-based polyol containing multiple types of castor oil-based polyols having a predetermined hydroxyl value and average functionality, and therefore can produce a vibration-damping material that exhibits excellent vibration-damping properties in a room temperature (0 to 35°C) environment. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a graph showing the loss factors tan δ of the vibration-damping materials obtained from the curable vibration-damping compositions of Examples 1 to 5. [Figure 2] 1 is a graph showing the loss factors tan δ of vibration-damping materials obtained from the curable vibration-damping compositions of Comparative Examples 1 to 5. DETAILED DESCRIPTION OF THE INVENTION

[0014] In the numerical ranges described in stages in this specification, the upper or lower limit of a certain numerical range can be arbitrarily combined with the upper or lower limit of another numerical range. In the numerical ranges described in this specification, the upper or lower limit of the numerical range may be replaced with a value shown in an example or a value that can be unambiguously derived from an example. In this specification, numerical values ​​connected with "to" mean a numerical range that includes the numbers before and after "to" as the upper and lower limits.

[0015] The curable vibration-damping composition of the present invention contains at least two or more castor oil-based polyols selected from the group consisting of: (A) a castor oil-based polyol having a hydroxyl value of 200 to 320 mgKOH / g and an average functionality of 2 or more but less than 3; (B) a castor oil-based polyol having a hydroxyl value of 100 to 199 mgKOH / g and an average functionality of less than 3; (C) a castor oil-based polyol having a hydroxyl value of 50 to 99 mgKOH / g and an average functionality of 2 or more but less than 3; (D) a castor oil-based polyol having a hydroxyl value of 49 mgKOH / g or less and an average functionality of 2 or more but less than 3; and (E) a castor oil-based polyol having a hydroxyl value of 200 to 400 mgKOH / g and an average functionality of 3 or more but less than 6, and the castor oil-based polyol has a weighted average hydroxyl value of 150 to 300 mgKOH / g; and an isocyanate compound.

[0016] The curable vibration-damping composition of the present invention is a two-component composition containing a base agent and a curing agent, and is used by mixing the base agent and the curing agent and curing the mixture. The curable vibration-damping composition of the present invention can also be used as a substantially one-component composition by quickly freezing the mixture after mixing the base agent and the curing agent and thawing it before use.

[0017] [Castor oil polyol] The main components of the curable vibration-damping composition are castor oil-based polyol (A) having a hydroxyl value of 200 to 320 mgKOH / g and an average functionality of 2 or more and less than 3 (hereinafter, sometimes simply referred to as "castor oil-based polyol (A)"); castor oil-based polyol (B) having a hydroxyl value of 100 to 199 mgKOH / g and an average functionality of less than 3 (hereinafter, sometimes simply referred to as "castor oil-based polyol (B)"); and castor oil-based polyol (C) having a hydroxyl value of 50 to 99 mgKOH / g and an average functionality of 2 or more and less than 3 (hereinafter, sometimes simply referred to as "castor oil-based polyol (C)"). a castor oil-based polyol (C)) having a hydroxyl value of 49 mgKOH / g or less and an average functionality of 2 or more and less than 3 (hereinafter simply referred to as "castor oil-based polyol (D)"), and a castor oil-based polyol (E) having a hydroxyl value of 200 to 400 mgKOH / g and an average functionality of 3 or more and less than 6 (hereinafter simply referred to as "castor oil-based polyol (E)"), and comprising at least two or more castor oil-based polyols having a weighted average hydroxyl value of 150 to 300 mgKOH / g.

[0018] By including any two or more types of castor oil-based polyols from castor oil-based polyols (A) to (E) having different hydroxyl values ​​and average functional groups, the vibration-damping material produced by curing the curable vibration-damping composition has various distances between crosslinking points, and the peak temperature of tan δ is adjusted to be around room temperature (0 to 35°C).The temperature range in which tan δ is 0.3 or more is wide, and the vibration-damping material has excellent vibration-damping properties over a wide temperature range around room temperature.

[0019] In the damping material, which is a cured product of the curable vibration-damping composition, it is preferable that the hydroxyl groups (-OH) of the castor oil-based polyol remain. By leaving the hydroxyl groups of the castor oil-based polyol remaining in the vibration-damping material, the peak tan δ can be increased while maintaining the peak temperature of tan δ at room temperature, and the vibration-damping material has better vibration-damping properties at room temperature.

[0020] Castor oil is a carboxylic acid triglyceride obtained from castor seeds, and the majority of the carboxylic acid ester moiety, usually 80 to 95% by mass, is ricinoleic acid ester, with the remainder being palmitic acid ester, stearic acid ester, oleic acid ester, linoleic acid ester, linolenic acid ester, etc.

[0021] The castor oil-based polyol is not particularly limited, and examples thereof include an ester exchange product of at least one of castor oil and alkylene oxide adducts of castor oil with at least one of alcohol, polyester polyol, and polyether polyol; an ester compound of castor oil fatty acid (a fatty acid obtained from castor oil, which is usually a mixture of ricinoleic acid, oleic acid, etc.) with at least one of alcohol, polyester polyol, and polyether polyol; a diol-type partially dehydrated or partially acylated castor oil product; a hydrogenation product of each of the above ester exchange products, the above ester compound, and the above partial dehydrated or partially acylated product; and a compound obtained by polymerizing castor oil to obtain polymerized castor oil and then reacting the ester exchange product of the obtained polymerized castor oil with caprolactone.

[0022] The main component of the curable vibration-damping composition contains at least two of the castor oil-based polyols (A) to (E), and these castor oil-based polyols (A) to (E) differ from the other castor oil-based polyols in either their hydroxyl value or their average functionality. The hydroxyl value and the average functionality of the castor oil-based polyols (A) to (E) are adjusted as follows. For example, this can be achieved by controlling the number of hydroxyl groups in the alcohol component when a carboxylic acid triglyceride is transesterified with at least one alcohol component selected from alcohols, polyester polyols, and polyether polyols, or by controlling the number of hydroxyl groups in the alcohol, polyester polyol, and polyether polyol when a fatty acid derived from castor oil is esterified with at least one alcohol, polyester polyol, and polyether polyol.

[0023] Commercially available castor oil-based polyols (A) to (E) can be used. The castor oil-based polyol (A) is commercially available, for example, from Ito Oil Mills under the trade names "URIC H-62" and "URIC AC-009" and from Toyokuni Oil Mills under the trade name "HS 2G 270B."

[0024] Castor oil-based polyol (B) is commercially available, for example, from Toyokuni Oil Mills under the trade names "HS 2G-120" and "HS 2G 160R" and from Ito Oil Mills under the trade name "URIC Y-403."

[0025] The castor oil-based polyol (C) is commercially available, for example, from Ito Oil Mills under the trade name "URIC H-1830."

[0026] The castor oil-based polyol (D) is commercially available, for example, from Ito Oil Mills under the trade names "URIC PH5001" and "URIC HF-2009."

[0027] Castor oil-based polyols (E) are commercially available, for example, from Ito Oil Mills under the trade names "URIC F-97," "URIC H-102," "URIC H-870," and "URIC H-854."

[0028] The hydroxyl value of the castor oil-based polyol (A) is 200 mgKOH / g or more, preferably 210 mgKOH / g or more, and more preferably 220 mgKOH / g or more. The hydroxyl value of the castor oil-based polyol (A) is 320 mgKOH / g or less, preferably 300 mgKOH / g or less, more preferably 280 mgKOH / g or less, and more preferably 270 mgKOH / g or less.

[0029] The hydroxyl value of the castor oil-based polyol (B) is 100 mgKOH / g or more, preferably 110 mgKOH / g or more, and more preferably 120 mgKOH / g or more. The hydroxyl value of the castor oil-based polyol (A) is 199 mgKOH / g or less, preferably 170 mgKOH / g or less, more preferably 150 mgKOH / g or less, and more preferably 130 mgKOH / g or less.

[0030] The hydroxyl value of the castor oil-based polyol (C) is 50 mgKOH / g or more, preferably 60 mgKOH / g or more, more preferably 70 mgKOH / g or more, and more preferably 80 mgKOH / g or more. The hydroxyl value of the castor oil-based polyol (A) is 99 mgKOH / g or less, preferably 95 mgKOH / g or less, more preferably 90 mgKOH / g or less, and more preferably 85 mgKOH / g or less.

[0031] The hydroxyl value of the castor oil-based polyol (D) is preferably 30 mgKOH / g or more, more preferably 35 mgKOH / g or more, and more preferably 40 mgKOH / g or more. The hydroxyl value of the castor oil-based polyol (A) is 49 mgKOH / g or less, preferably 47 mgKOH / g or less, and more preferably 46 mgKOH / g or less.

[0032] The hydroxyl value of the castor oil-based polyol (E) is 200 mgKOH / g or more, preferably 250 mgKOH / g or more, more preferably 280 mgKOH / g or more, more preferably 310 mgKOH / g or more, and more preferably 320 mgKOH / g or more. The hydroxyl value of the castor oil-based polyol (A) is 400 mgKOH / g or less, preferably 380 mgKOH / g or less, more preferably 360 mgKOH / g or less, and more preferably 340 mgKOH / g or less.

[0033] The average number of functional groups of the castor oil-based polyol (A) is 2 or more and less than 3, preferably 2 to 2.5, and more preferably 2 to 2.3.

[0034] The average number of functional groups of the castor oil-based polyol (B) is less than 3, preferably 2 to 2.9, more preferably 2 to 2.5, and even more preferably 2 to 2.3.

[0035] The average number of functional groups of the castor oil-based polyol (C) is 2 or more and less than 3, preferably 2 to 2.7, and more preferably 2 to 2.5.

[0036] The average number of functional groups of the castor oil-based polyol (D) is 2 or more, preferably 2 to 2.5, and more preferably 2 to 2.3.

[0037] The average number of functional groups of the castor oil-based polyol (E) is 3 or more and 6 or less, preferably 3 to 5, more preferably 3 to 4, and even more preferably 3 to 3.5.

[0038] The content of the castor oil-based polyol (A) in the castor oil-based polyol is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 15% by mass or more. The content of the castor oil-based polyol (A) in the castor oil-based polyol is preferably 35% by mass or less, more preferably 30% by mass or less, and more preferably 28% by mass or less. When the content of the castor oil-based polyol (A) is 5% by mass or more, the temperature range in the vibration damping material where tan δ is 0.3 or more is widened, and the vibration damping material has excellent vibration damping properties over a wider range of room temperatures. When the content of the castor oil-based polyol (A) is 35% by mass or less, the temperature range in the vibration damping material where tan δ is 0.3 or more is widened, and the vibration damping material has excellent vibration damping properties over a wider range of room temperatures.

[0039] The content of the castor oil-based polyol (B) in the castor oil-based polyol is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 15% by mass or more. The content of the castor oil-based polyol (B) in the castor oil-based polyol is preferably 60% by mass or less, more preferably 55% by mass or less, more preferably 50% by mass or less, more preferably 40% by mass or less, more preferably 35% by mass or less, more preferably 30% by mass or less, and more preferably 28% by mass or less. When the content of the castor oil-based polyol (B) is 5% by mass or more, the temperature range in the vibration damping material where tan δ is 0.3 or more is broadened, and the vibration damping material has excellent vibration damping properties over a wider range of room temperatures. When the content of the castor oil-based polyol (B) is 60% by mass or less, the temperature range in the vibration damping material where tan δ is 0.3 or more is broadened, and the vibration damping material has excellent vibration damping properties over a wider range of room temperatures.

[0040] The content of the castor oil-based polyol (C) in the castor oil-based polyol is preferably 5% by mass or more, more preferably 10% by mass or more, and more preferably 15% by mass or more. The content of the castor oil-based polyol (C) in the castor oil-based polyol is preferably 35% by mass or less, more preferably 30% by mass or less, and more preferably 28% by mass or less. When the content of the castor oil-based polyol (C) is within the above range, the peak temperature of tan δ in the vibration damping material is room temperature and the peak height at the peak temperature of tan δ becomes higher, so that the vibration damping material has better vibration damping properties at room temperature.

[0041] The content of the castor oil-based polyol (D) in the castor oil-based polyol is preferably 10% by mass or more, more preferably 15% by mass or more, and more preferably 18% by mass or more. The content of the castor oil-based polyol (D) in the castor oil-based polyol is preferably 35% by mass or less, more preferably 30% by mass or less, more preferably 28% by mass or less, and more preferably 25% by mass or less. When the content of the castor oil-based polyol (D) is within the above range, the peak temperature of tan δ in the vibration damping material is room temperature and the peak height at the peak temperature of tan δ becomes higher, so that the vibration damping material has better vibration damping properties at room temperature.

[0042] The content of the castor oil-based polyol (E) in the castor oil-based polyol is preferably 10% by mass or more, more preferably 15% by mass or more, more preferably 18% by mass or more, and more preferably 20% by mass or more. The content of the castor oil-based polyol (E) in the castor oil-based polyol is preferably 55% by mass or less, more preferably 53% by mass or less, more preferably 50% by mass or less, preferably 35% by mass or less, more preferably 30% by mass or less, and more preferably 25% by mass or less. When the content of the castor oil-based polyol (E) is within the above range, the peak temperature of tan δ in the vibration damping material is room temperature and the peak height at the peak temperature of tan δ becomes higher, so that the vibration damping material has better vibration damping properties at room temperature.

[0043] The preferred ranges for the content of each of the castor oil-based polyols (A) to (E) have been described above. Meanwhile, the curable vibration-damping composition of the present invention contains multiple types of castor oil-based polyols (A) to (E), thereby allowing a variety of inter-crosslink distances to be present in the vibration-damping material. Therefore, the vibration-damping material has a high value of tan δ over a wide range of room temperature environments. From this perspective, the contents of the castor oil-based polyols (A) to (E) may be adjusted as follows:

[0044] When the curable vibration-damping composition contains the castor oil-based polyol (E), it is possible to adjust the peak temperature of tan δ of the vibration-damping material to room temperature and to increase the peak height at the peak temperature of tan δ, and the vibration-damping material has excellent vibration-damping properties over a wide temperature range including room temperature.

[0045] The content of the castor oil-based polyol (E) in the castor oil-based polyol is preferably 10% by mass or more, more preferably 15% by mass or more, more preferably 18% by mass or more, and more preferably 20% by mass or more. The content of the castor oil-based polyol (E) in the castor oil-based polyol is preferably 55% by mass or less, more preferably 53% by mass or less, more preferably 50% by mass or less, preferably 35% by mass or less, more preferably 30% by mass or less, and more preferably 25% by mass or less. When the content of the castor oil-based polyol (E) is within the above range, the peak temperature of tan δ in the vibration damping material is room temperature and the peak height at the peak temperature of tan δ becomes higher, so that the vibration damping material has better vibration damping properties at room temperature.

[0046] When the castor oil-based polyol (E) is contained in the castor oil-based polyol, the preferred contents of the castor oil-based polyols (A) to (D) may be adjusted as follows.

[0047] When the castor oil-based polyol contains K types of castor oil-based polyols (A) to (D) and a castor oil-based polyol (E), the content of the Kth castor oil-based polyol among the castor oil-based polyols (A) to (D) is defined as Wk (mass%), and the content of the castor oil-based polyol (E) is defined as We (mass%). K is a natural number from 1 to 4. The total amount of W1 to Wk is adjusted to be (100-We) mass%.

[0048] The K types of castor oil-based polyols contained in the castor oil-based polyol do not need to be contained evenly, but in order to introduce various distances between crosslinking points into the vibration damping material, it is preferable that the K types of castor oil-based polyols contained in the castor oil-based polyol are contained in roughly the same amounts, rather than containing only a specific castor oil-based polyol in excess.

[0049] The content Wk of each of the K types of castor oil-based polyols contained in the castor oil-based polyol preferably satisfies the following formula (1), and more preferably satisfies the following formula (2).

[0050] [(100-We) / K]-10≦Wk≦[(100-We) / K]+10 (1) [(100-We) / K]-5≦Wk≦[(100-We) / K]+5 (2)

[0051] When the castor oil-based polyol does not contain the castor oil-based polyol (E) but contains K types of castor oil-based polyols (A) to (D), the content of the Kth castor oil-based polyol among the castor oil-based polyols (A) to (D) is defined as Wk (mass%), where K is a natural number from 1 to 4. The total amount of W1 to Wk is adjusted to 100 mass%.

[0052] The content Wk of each of the K types of castor oil-based polyols contained in the castor oil-based polyol preferably satisfies the following formula (3), and more preferably satisfies the following formula (4).

[0053] (100 / K)-10≦Wk≦(100 / K)+10 (3) (100 / K)-5≦Wk≦(100 / K)+5 (4)

[0054] The castor oil-based polyol preferably contains castor oil-based polyols (A), (B), (C) and (E).

[0055] It is more preferable that the castor oil-based polyol contains castor oil-based polyols (A), (B), (C) and (E), and that the contents of the castor oil-based polyols (A), (B), (C) and (E) each contain the formula (1).

[0056] It is more preferable that the castor oil-based polyol contains castor oil-based polyols (A), (B), (C) and (E), and that the contents of the castor oil-based polyols (A), (B), (C) and (E) each contain the formula (2).

[0057] Here, the hydroxyl value (mgKOH / g) of the castor oil-based polyol can be determined by the acetylation method or the phthalation method in accordance with JIS K1557-1 (2007).

[0058] The average number of functional groups of the castor oil-based polyols (A) to (E) refers to the average number (arithmetic mean value) of hydroxyl groups per molecule.

[0059] The weighted average hydroxyl value of the entire castor oil-based polyol is a value calculated as follows: If a castor oil-based polyol contains a total of n types of castor oil-based polyols, and the hydroxyl value of the kth castor oil-based polyol is Hk [mgKOH / g] and the content of the kth castor oil-based polyol is Wk (parts by mass), the value calculated based on the following formula is the weighted average H [mgKOH / g] of the hydroxyl value content of the castor oil-based polyols.

[0060] [ka]

[0061] As described above, the castor oil-based polyol contains at least two castor oil-based polyols from the castor oil-based polyols (A) to (E). The weighted average hydroxyl value of the entire castor oil-based polyols is adjusted to 150 to 300, thereby achieving a moderate crosslink density with various distances between crosslink points in the crosslinked structure of the vibration-damping material, which is the cured product of the curable vibration-damping composition. Because the curable vibration-damping composition contains castor oil polyols with various molecular weights, microblank movement occurs within the cured product of the curable vibration-damping composition at various temperatures. Therefore, the cured product, i.e., the vibration-damping material, produced by curing the curable vibration-damping composition exhibits excellent vibration-damping properties over a wide temperature range, from room temperature (0 to 35°C).

[0062] [Isocyanate compounds] The curing agent of the curable vibration-damping composition contains an isocyanate compound, which reacts with the hydroxyl groups of the castor oil-based polyol contained in the base resin to form urethane bonds, thereby forming a crosslinked structure.

[0063] The isocyanate compound is not particularly limited as long as it can react with the hydroxyl groups of the castor oil-based polyol to form a urethane bond and thereby form a crosslinked structure, and examples thereof include diphenylmethane diisocyanate (hereinafter abbreviated as "MDI" [e.g., 2,2'-MDI, 2,4'-MDI, 4,4'-MDI, polymeric MDI (crude MDI)]), tolylene diisocyanate (hereinafter abbreviated as "TDI" [e.g., 2,4-TDI, 2,6-TDI]), naphthalene diisocyanate, and the like. Examples of the isocyanate include aromatic polyisocyanates such as methyl anate, aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, and xylylene diisocyanate, carbodiimide-modified products of the above polyisocyanates, and polyurethane prepolymers obtained by reacting an isocyanate compound with a low-molecular-weight polyol, among which diphenylmethane diisocyanate (MDI) is preferred, and polymeric MDI (crude MDI) is more preferred. The isocyanate compounds may be used alone or in combination of two or more.

[0064] In the curable vibration-damping composition, the ratio of the isocyanate amount (mmoL / g) of the isocyanate compound to the hydroxyl group amount (mmoL / g) of the entire castor oil-based polyol (isocyanate amount of the isocyanate compound / hydroxyl group amount of the entire castor oil-based polyol) is preferably less than 1.0, more preferably 0.90 or less, more preferably 0.80 or less, and even more preferably 0.70 or less. When the ratio of the isocyanate amount (mmoL / g) of the isocyanate compound to the hydroxyl group amount (mmoL / g) of the entire castor oil-based polyol is less than 1.0, the hydroxyl groups of the castor oil-based polyol remain in the vibration-damping material, thereby increasing the peak of tan δ while maintaining the peak temperature of tan δ at room temperature, and the vibration-damping material has better vibration-damping properties at room temperature.

[0065] The isocyanate amount of the isocyanate compound is a value calculated from the NCO mol% amount measured in accordance with JIS K1603-1 (2007). The hydroxyl group amount (mmoL / g) of the castor oil-based polyol is a value calculated from the hydroxyl value measured by the acetylation method or phthalation method in accordance with JIS K1557-1 (2007).

[0066] [Catalysts and other additives] The curable vibration-damping composition may contain a curing catalyst. The curing catalyst may be contained in either the base agent or the curing agent, but is preferably contained in the base agent.

[0067] The curing catalyst is not particularly limited, and examples thereof include divalent tin compounds such as tin octoate, tin naphthenate, tin stearate, and tin neodecanoate; tetravalent organic tin compounds such as dibutyltin dioctoate, dibutyltin dilaurate, dioctyltin diversatate, dibutyltin bistriethoxysilicate, dibutyltin dioleyl maleate, dibutyltin diacetate, 1,1,3,3-tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane, dibutyltin oxybisethoxysilicate, dibutyltin oxide, a reaction product of dibutyltin oxide with a phthalic acid ester, and a reaction product of dibutyltin oxide with a maleic acid diester; and tetravalent organic tin compounds such as dibutyltin diacetylacetonate. The curing catalysts may be used alone or in combination of two or more.

[0068] The curable vibration-damping composition may contain additives such as wetting and dispersing agents, surface conditioners, rheology control agents, leveling agents, plasticizers, solvents, etc., as long as the physical properties of the composition are not impaired. It is preferable that the curable vibration-damping composition does not contain a solvent (is solvent-free) because it is less likely to undergo thermal deformation or shrinkage upon curing.

[0069] [Curable vibration damping composition] The base material of the curable vibration-damping composition can be produced by mixing any two or more castor oil-based polyols selected from the castor oil-based polyols (A) to (E) in a conventional manner. The curing agent of the curable vibration-damping composition contains a desired isocyanate compound. Additives such as curing catalysts may be contained in either the base material or the curing agent, but are preferably contained in the base material.

[0070] The curable vibration-damping composition is prepared by mixing a base material and a curing agent, whereby the castor oil-based polyol in the base material reacts with the isocyanate compound in the curing agent to form a crosslinked structure via urethane bonds, resulting in curing and producing a cured product. This cured product can be suitably used as a vibration-damping material.

[0071] The curable vibration-damping composition is used by mixing the base agent and the curing agent and then applying the mixture to the surface of the object to be damped whose vibrations are to be suppressed. The object to be damped is not particularly limited as long as it generates vibrations, and examples thereof include components of industrial machinery, automobiles, home appliances, etc.

[0072] The curable vibration-damping composition is in liquid form and hardens when applied to the desired portion of the vibration-damped body and then cured at room temperature, so that the vibration-damping material can be easily laminated and integrated onto the surface of the vibration-damped body.

[0073] The damping material of the damped body has excellent damping properties in a room temperature atmosphere of 0 to 35°C, and can effectively suppress vibrations occurring in the damped body when it is in use.

[0074] The vibration-damping material has a peak temperature of loss tangent (tan δ) determined by solid viscoelasticity measurement of 0 to 35°C, and has excellent vibration-damping properties in a room temperature atmosphere.

[0075] In the vibration-damping material, the peak height at the peak temperature of the loss tangent (tan δ) determined by solid viscoelasticity measurement is preferably 1.00 or more. When the peak height at the peak temperature of tan δ is 1.00 or more, the vibration-damping material has excellent vibration-damping properties.

[0076] In the vibration-damping material, the temperature range in which the loss tangent (tanδ) determined by solid viscoelasticity measurement is 0.3 or more is preferably 50° C. or more, and more preferably 52° C. or more. When the temperature range in which tanδ is 0.3 or more is 50° C. or more, the vibration-damping material exhibits excellent vibration-damping properties over a wide temperature range.

[0077] The loss tangent (tan δ) determined by measuring the solid viscoelasticity of a vibration-damping material is a value measured in the following manner.

[0078] The loss tangent (tanδ) of the vibration-damping material is determined by measuring the solid viscoelasticity using a dynamic viscoelasticity device. Specifically, the distance between chucks is 20 mm, and the lower limit elastic modulus is 1.0 × 10 5The loss tangent (tanδ) can be measured using a dynamic viscoelasticity apparatus in the range of -20°C to 80°C under the following conditions: Pa, lower limit dynamic force 0 cN, heating rate 2°C / min, frequency 1 Hz, strain rate 0.06%, and upper limit elongation 50%. Note that the dynamic viscoelasticity apparatus can be a measuring device commercially available from IT Measurement & Control Co., Ltd. under the product name "DVA-200." [Example]

[0079] The present invention will be described in more detail below using examples, but the present invention is not limited thereto. Specific numerical values ​​of blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit values ​​(numeric values ​​defined as "equal to or less than") or lower limit values ​​(numeric values ​​defined as "equal to or greater than") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the "Description of Embodiments."

[0080] The following raw materials were used in the production of the curable vibration-damping compositions of the Examples and Comparative Examples. [Castor oil polyol] Castor oil-based polyol (A) (manufactured by Ito Oil Mills, trade name "URIC H-62", hydroxyl value (OHv): 260 mg KOH / g, average functionality: 2) Castor oil-based polyol (B1) (Toyokuni Oil Mills, product name "HS 2G-120", hydroxyl value (OHv): 122 mg KOH / g, average functionality: 2) Castor oil polyol (B2) (manufactured by Ito Oil Mills, trade name "URIC H-30", hydroxyl value (OHv): 160 mg KOH / g, average functionality: 2.7) Castor oil-based polyol (C) (manufactured by Ito Oil Mills, product name "URIC H-1830", hydroxyl value (OHv): 82 mg KOH / g, average functionality: 2.3) Castor oil-based polyol (D) (manufactured by Ito Oil Mills, product name "URIC PH5001", hydroxyl value (OHv): 45 mg KOH / g, average functionality: 2) Castor oil-based polyol (E) (manufactured by Ito Oil Mills, trade name "URIC F-97", hydroxyl value: 335 mg KOH / g, average functionality: 3)

[0081] [Isocyanate compounds] Polymeric MDI (crude MDI) (Sumidur 44V manufactured by Sumika Covestro Urethane Co., Ltd.)

[0082] [Curing catalyst] 1,1,3,3-Tetrabutyl-1,3-dilauryloxycarbonyl-distannoxane

[0083] [Crosslinking agent (chain extender)] Diethylene glycol (hydroxyl value: 160 mg KOH / g, boiling point: 245°C)

[0084] (Examples 1 to 5, Comparative Examples 1 to 5) A two-component curable vibration-damping composition was prepared, which consisted of a base material containing the castor oil-based polyols (A) to (E) in the predetermined amounts (parts by mass) shown in Tables 1 and 2, and a curing agent containing the isocyanate compound, curing catalyst, and crosslinking agent in the predetermined amounts (parts by mass) shown in Tables 1 and 2.

[0085] For the resulting curable vibration-damping compositions, the weighted average hydroxyl value of the entire castor oil-based polyol is shown in the column "Weighted average hydroxyl value" in Tables 1 and 2.

[0086] For the obtained curable vibration-damping composition, the ratio of the isocyanate amount (mmoL / g) of the isocyanate compound to the hydroxyl group amount (mmoL / g) of the entire castor oil-based polyol (isocyanate amount of the isocyanate compound / hydroxyl group amount of the castor oil-based polyol) was recorded in the "NCO / OH" column.

[0087] The loss tangent (tan δ) of the obtained curable vibration-damping composition was measured by solid viscoelasticity measurement according to the following procedure, and the results are shown in Tables 1 and 2 and in FIGS.

[0088] [Solid viscoelasticity measurement] After mixing the main component and curing agent of the curable vibration-damping composition, the curable vibration-damping composition was fed into a molding frame measuring 30 mm in length, 5 mm in width, and 0.5 mm in thickness, and cured at 23°C for 20 hours to produce a vibration-damping material.

[0089] The loss tangent (tanδ) of the vibration-damping material determined by solid viscoelasticity measurement is measured using a dynamic viscoelasticity device. Specifically, a dynamic viscoelasticity device (manufactured by IT Measurement & Control Co., Ltd., product name "DVA-200") is used, with a chuck distance of 20 mm and a lower limit elastic modulus of 1.0 × 10 5 The loss tangent (tanδ) was measured in the range of -20°C to 80°C under the conditions of: Pa, lower limit force to 0 cN, temperature rise rate 2°C / min, frequency 1 Hz, strain rate 0.06%, and upper limit elongation rate 50%. Note that for Comparative Example 6, the measurement was carried out in the range of 0°C to 100°C due to the characteristics of the vibration-damping material.

[0090] The peak position, peak height and temperature range where tan δ is 0.3 or more of the loss factor tan δ are shown in the columns "tan δ peak position (°C)", "tan δ peak height" and "tan δ temperature range (°C)", respectively.

[0091] [Table 1]

[0092] [Table 2] [Industrial Applicability]

[0093] The curable vibration-damping composition of the present invention can produce a vibration-damping material that exhibits excellent vibration-damping properties in a room temperature (0 to 35° C.) environment. By applying the curable vibration-damping composition to an object to be damped, such as a component part of industrial machinery, automobiles, home appliances, etc., it is possible to impart excellent vibration-damping properties to the object to be damped.

Claims

1. a castor oil-based polyol containing at least two or more selected from the group consisting of: a castor oil-based polyol (A) having a hydroxyl value of 200 to 320 mgKOH / g and an average functionality of 2 or more but less than 3; a castor oil-based polyol (B) having a hydroxyl value of 100 to 199 mgKOH / g and an average functionality of less than 3; a castor oil-based polyol (C) having a hydroxyl value of 50 to 99 mgKOH / g and an average functionality of 2 or more but less than 3; a castor oil-based polyol (D) having a hydroxyl value of 49 mgKOH / g or less and an average functionality of 2 or more but less than 3; and a castor oil-based polyol (E) having a hydroxyl value of 200 to 400 mgKOH / g and an average functionality of 3 or more but less than 6, and having a weighted average hydroxyl value of 150 to 300 mgKOH / g; and an isocyanate compound.

2. 2. The curable vibration-damping composition according to claim 1, wherein the ratio of the isocyanate amount of the isocyanate compound to the hydroxyl group amount of the castor oil-based polyol (isocyanate amount of the isocyanate compound / hydroxyl group amount of the castor oil-based polyol) is less than 1.

0.

3. 3. The curable vibration-damping composition according to claim 1, wherein the composition is applied to an object to be damped.

4. A vibration damping material comprising a cured product of the curable vibration damping composition according to claim 1 or 2.

5. 5. The vibration damping material according to claim 4, wherein the peak temperature of the loss factor tan δ is 0 to 35°C.

Images