JP2005320431A - Cushion for automobile seat made from flexible polyurethane foam derived from soybean oil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cushion for an automobile seat made from a flexible polyurethane foam with ≥30% impact resilience by using a vegetable-derived polyol. <P>SOLUTION: This cushion for the automobile seat is made from a flexible polyurethane foam obtained from a polyisocyanate compound and a polyol obtained by adding an alkylene oxide in a molar ratio of ethylene oxide/propylene oxide=20/80-5/95 to an epoxidized soybean oil ring-opened with an alcohol. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cushion for automobile seats comprising a flexible polyurethane foam obtained from a polyol obtained by adding ethylene oxide and propylene oxide to an epoxidized soybean oil ring-opened with alcohol and a polyisocyanate compound.

  Technology development efforts are being carried out on a global scale with the aim of preventing global warming and building a recycling-oriented society. Carbon dioxide is one of the gases that cause global warming, and there is a need to reduce its emissions. Oil and coal are limited and non-renewable resources, and increase the amount of carbon dioxide in the atmosphere by burning and discarding. On the other hand, plant-derived substances are renewable resources produced by plants that take in the amount of carbon dioxide in the atmosphere, and the amount of carbon dioxide in the atmosphere does not increase even when burned. For this reason, there is a movement to use plant-derived substances instead of petroleum and coal-derived substances.

  The soft polyurethane foam used for automobile seat cushions is a shredder-treated and incinerated conventional soft urethane foam used for disposing of automobiles, and is a petroleum-derived substance. ing.

  The polyurethane foam has a structure containing bubbles by using a foaming agent in a resin obtained using a polyisocyanate compound and a polyol compound as main raw materials, and is used as a heat insulating material, a sound insulating material, an impact absorbing material, and a cleaning tool. It is used. Among these, the flexible polyurethane foam is lightweight and excellent in impact absorbing ability, so that it is widely used as a cushion for automobile seats. Patent Document 1 proposes a cushion for automobile seats using a specific synthetic polyol.

As shown also in this patent document 1 etc., the polyether polyol which is a petroleum origin material has been used for many years as a polyol compound which is one of the raw materials of a flexible polyurethane foam. If a polyol compound of petroleum-derived material is used, the value of the rebound resilience of the resulting cushion can be easily obtained around 55%, and is suitably used for a cushion for an automobile seat.
On the other hand, plant-derived substances such as castor oil, aerated soybean oil (Patent Document 2), epoxidized soybean oil-alcohol ring-opened products (Patent Document 3 and Patent Document 4), etc. were used as polyether materials. Polyurethane foams are also known. Although these polyurethane foams are plant-derived and circulated, they have limited structures that can be designed, and furthermore, their resilience is insufficient, so that they cannot be used as cushions for automobile seats. When the applicants conducted a verification experiment, the resilience was about 15 to 20%.

  Patent Document 5 describes a polyurethane foam obtained by opening a ring of epoxidized vegetable oil with an alcohol or a fatty acid and replacing a part of the polyol with a nonionic surfactant to which an alkylene oxide is added. In order to provide a function as a nonionic surfactant, only ethylene oxide was used as the alkylene oxide, and it could not be used as a cushion for an automobile seat requiring rebound resilience.

  In Toyo University, Ogura, Matsunaga et al. In Non-Patent Document 1, 65% sulfuric acid and 30% hydrogen peroxide water are mixed and heated using waste soybean oil as a raw material to introduce a hydroxyl group into the double bond part of soybean oil. A method for producing urethane foam by refining and mixing and stirring this, polymeric diisocyanate, water, amine catalyst, and silicone foaming agent is reported.

Claims of Japanese Patent Application Laid-Open No. 7-206961 Claims of JP-T-2002-524627 Claims of JP 59-207914 A Claims of JP-A-63-41523 Surfactant 1 and Surfactant 2 in Claims and Examples of JP-T 9-505846 2002 Toyo University Master's Thesis Collection

  An object of the present invention is to obtain a cushion for an automobile seat made of a flexible polyurethane foam using a plant-derived polyol and having a rebound resilience of 30% or more.

  As a result of intensive studies on the above problems, the inventors of the present invention made a flexible polyurethane foam having high impact resilience by ring-opening epoxidized soybean oil with alcohol and then adding ethylene oxide / propylene oxide at a constant molar ratio. The present invention was completed by finding that a cushion for automobile seats was obtained. That is, the present invention is for an automobile seat comprising a flexible polyurethane foam obtained by adding alkylene oxide to an epoxidized soybean oil ring-opened with alcohol at a molar ratio of ethylene oxide / propylene oxide = 20/80 to 5/95. A cushion is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the cushion for motor vehicle seats made from a flexible polyurethane foam which uses a plant-derived polyol and whose impact resilience is 30% or more can be provided.

  In the present invention, epoxidized soybean oil is epoxidized by oxidizing all or part of unsaturated bonds of a mixed fatty acid mainly composed of fatty acids having an unsaturated bond and soybean oil having a triester structure of glycerin. It is a compound. The epoxidized soybean oil ring-opened with alcohol has a structure in which an epoxy group is converted into a hydroxy group and an alkoxy group by addition reaction of the alcohol with the epoxy group.

  The number of epoxy groups in the raw material epoxidized soybean oil is preferably 2 to 6, and the rebound resilience of the resulting flexible polyurethane foam is preferably 30% or more, particularly 40% or more for use in a cushion for an automobile seat. 2.5 to 4 is more preferable, and 2.7 to 3.3 is most preferable.

  The alcohol used for ring-opening the epoxidized soybean oil of the present invention is not particularly limited, but the reactivity with the epoxidized soybean oil and the reactivity between the alcohol ring-opened product and the alkylene oxide are improved. C1-C4 primary alcohols are preferred, methanol and ethanol are more preferred, and methanol is most preferred.

  Ring opening of epoxidized soybean oil with alcohol is usually carried out with an acid catalyst. Examples of the acid catalyst include sulfuric acid, perchloric acid, boron trifluoride, tin chloride, titanium tetrachloride, and the like.

  The molar ratio of ethylene oxide to propylene oxide added after ring opening of the epoxidized soybean oil of the present invention with alcohol is 20/80 to 5/95. If there is more ethylene oxide than the above range, the impact resilience cannot reach 30%, and if it is less, the reactivity with isocyanate is insufficient, and a large amount of tin catalyst whose use is being restricted must be used. is there. Propylene oxide is expected to improve resilience and ethylene oxide is expected to improve reactivity with isocyanates. Therefore, when ethylene oxide and propylene oxide are block-polymerized, ethylene oxide is later polymerized to ensure reactivity with isocyanate. Therefore, it is preferable.

The molecular weight of the obtained polyether polyol is preferably 1500 to 8000, and if it is less than 1500, the amount of propylene oxide to be added is insufficient and the rebound resilience cannot reach 30%. It is not preferable because the viscosity becomes very high and it is difficult to handle.
However, since it is preferable that the addition amount of alkylene oxide is small in order to reduce environmental burden by using soybean oil as a raw material, the molecular weight is more preferably 3000 to 6000.
Here, since soybean oil is a triester of mixed fatty acid and glycerin containing a large amount of unsaturated fatty acids, all unsaturated groups are epoxidized by using glycerol and oleic acid triester as a representative example of soybean oil, and alcohol. The structural formula (I) when the ring is opened at is shown below as a specific example.

  The polyisocyanate used in the present invention is not particularly limited as long as it has two or more isocyanate groups in the molecule. For example, aliphatic diisocyanate, aromatic nucleus diisocyanate, alicyclic diisocyanate, biphenyl diisocyanate, diisocyanate of phenylmethane, triisocyanate, tetraisocyanate and the like can be mentioned.

  Examples of the aliphatic diisocyanate include methylene didisocyanate, dimethylene disisocyanate, trimethylene didisocyanate, tetramethylene didisocyanate, pentamethylene didisocyanate, hexamethylene didisocyanate, dipropyl ether diisocyanate, and 2,2. -Dimethylpentane diisocyanate, 3-methoxyhexane diisocyanate, octamethylene diisocyanate, 2,2,4-trimethylpentane diisocyanate, nonamethylene diisocyanate, decamethylene diisocyanate, 3-butoxyhexane diisocyanate, 1,4-butylene glycol dipropyl ether diisocyanate, Thiodihexyl diisocyanate, metaxylylene diisocyanate, paraxylylene diisocyanate, Examples include tetramethylxylylene diisocyanate.

  Examples of the aromatic nucleus diisocyanate include metaphenylene diisocyanate, paraphenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, dimethylbenzene diisocyanate, ethylbenzene diisocyanate, isopropylbenzene diisocyanate, tolidine diisocyanate, 1,4- Naphthalene diisocyanate, 1,5-naphthalene diisocyanate, 2,6-naphthalene diisocyanate, 2,7-naphthalene diisocyanate and the like can be mentioned.

  Examples of the alicyclic diisocyanate include hydrogenated xylylene diisocyanate and isophorone diisocyanate.

  Examples of biphenyl diisocyanate include biphenyl diisocyanate, 3,3′-dimethylbiphenyl diisocyanate, 3,3′-dimethoxybiphenyl diisocyanate, and the like.

  Examples of the diisocyanate of phenylmethane include diphenylmethane-4,4′-diisocyanate, 2,2′-dimethyldiphenylmethane-4,4′-diisocyanate, diphenyldimethylmethane-4,4′-diisocyanate, 2,5,2 ′. , 5′-tetramethyldiphenylmethane-4,4′-diisocyanate, cyclohexylbis (4-isocyanatophenyl) methane, 3,3′-dimethoxydiphenylmethane-4,4′-diisocyanate, 4,4′-dimethoxydiphenylmethane-3 3,3'-diisocyanate, 4,4'-diethoxydiphenylmethane-3,3'-diisocyanate, 2,2'-dimethyl-5,5'-dimethoxydiphenylmethane-4,4'-diisocyanate, 3,3'-dichloro Diphenyldimethylmethane-4,4'-diisocyanate, benzophenone- , 3'-diisocyanate, and the like.

  Examples of the triisocyanate include 1-methylbenzene-2,4,6-triisocyanate, 1,3,5-trimethylbenzene-2,4,6-triisocyanate, 1,3,7-naphthalene triisocyanate, and biphenyl. -2,4,4'-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, 3-methyldiphenylmethane-4,6,4'-triisocyanate, triphenylmethane-4,4 ', 4' ' -Triisocyanate, 1,6,11-undecane triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, tris (isocyanatephenyl) thiophosphate, etc. Is mentioned.

  Moreover, it may be used as a dimer or trimer (isocyanurate bond) of these polyisocyanate compounds, or may be used as a biuret by reacting with an amine. As the isocyanate to be used, a bifunctional polyisocyanate is used when the polyol is trifunctional or higher. However, when the polyol contains many bifunctional components, the use of a trifunctional or higher polyisocyanate can reduce the crosslinking density. It is preferable for moderate control.

  In the flexible polyurethane foam used in the present invention, water, pentane, n-hexane, formic acid, air, nitrogen, carbon dioxide and the like can be used as a foaming agent. Among these, it is preferable to use water. Water can foam the polyurethane resin by carbon dioxide generated by reacting with the polyisocyanate. Although the usage-amount of water changes with uses of a polyurethane foam, For example, in the case of the sheet | seat for motor vehicles, Preferably it is 1-10 mass parts with respect to 100 mass parts of polyols (total polyol component), More preferably, it is 2-6. Part by mass, most preferably 3 to 5 parts by mass.

  When producing the flexible polyurethane foam of the present invention, reactive foaming may be carried out in the range of isocyanate group / hydroxyl group = 0.8 to 1.5 (equivalent ratio, NCO index), particularly 0.9 to 1.2. preferable.

  Moreover, when manufacturing the flexible polyurethane foam of this invention, it is preferable to mix | blend a catalyst, a foam stabilizer, a crosslinking agent, etc. as needed.

  An amine compound can be added as a catalyst. Examples of the amine compound include N, N-dimethylcyclohexylamine, N, N-dicyclohexylmethylamine, N, N-dimethylbenzylamine, N, N-dimethylcetylamine, and triethylamine. N, N-dimethyldodecylamine, pyridine, N-methylmorpholine, N-ethylmorpholine, N, N, N′N′-tetramethylethylenediamine, N, N, N′N′-tetramethyl-1,3- Propanediamine, N, N, N′N′-tetramethyl-1,3-butanediamine, N, N, N′N′-tetramethyl-hexanediamine, methylenebis (dimethylcyclohexylamine), 3-dimethylamino-N , N-dimethylpropionic acid amide, N, N, N ′, N′-tetraethylmethylenediamine, bis- 2-dimethylaminoethyl ether, 2- (N, N-dimethylamino) ethyl-3- (N, N-dimethylamino) propyl ether, 4,4′-oxydiethylenedimorpholine, ethylene glycol bis (3-dimethylamino) Propyl) ether, N, N, N ′, N ′, N ″ -pentamethyldiethylenetriamine, N, N, N ′, N ′, N ″ -pentamethyldipropylenetriamine, N, N, N ′, N′— Tetra (3-dimethylaminopropyl) methanediamine, triethylenediamine, N, N′-dimethylpiperazine, N, N′-diethylpiperazine, N-methyl-N′-dimethylaminoethylpiperazine, N- (2-dimethylaminoethyl) ) Morpholine, 1,2-dimethylimidazole, 1,8-diazabicyclo (5,4,0) undecene-7 (DBU) , DBU phenolate, DBU carboxylate, DBU octylate, N, N'-dimethylaminoethanol, ethoxylated hydroxyamine, N, N-tetramethyl-1,3-diamino-2-propanol, N, N, N'- Trimethylaminoethylethanolamine, N, N, N′-trimethylaminopropylethanolamine, N-methyl-N ′-(2-hydroxyethyl) piperazine, N- (2-hydroxyethyl) morpholine, 1- (2-hydroxy Propyl) imidazole, 2,4,6-tris (dimethylaminomethyl) phenol, 1,4-bis (2-hydroxypropyl) -2-methylpiperazine, triethanolamine, 3,3-diamino-N-methyldipropyl Amine, bis (dimethylaminopropyl) amine, morpholine, etc. Can be used.

  Further, when the polyurethane foam is produced by the production method of the present invention, it is used in combination with the amine compound as a catalyst, for example, dibutyltin dilaurate, dibutyltin diacetate, diethyltin diacetate, dihexyltin diacetate, di-2. -Organic tin compounds such as ethylhexyl tin oxide, dioctyl tin dioxide, stannous octoate, stannous oleate, and metal compounds such as potassium acetate, sodium bicarbonate, calcium carbonate can be used.

  As the foam stabilizer, those used in the production of ordinary polyurethane foams can be used, and examples thereof include silicone foam stabilizers and fluorine foam stabilizers, and silicone foam stabilizers are particularly preferred. When these foam stabilizers are used, uniform bubbles can be formed.

  In the present invention, a crosslinking agent can be used as necessary. The crosslinking agent is a compound having two or more functional groups having active hydrogen such as a hydroxyl group, a primary amino group or a secondary amino group, and a polyol compound having 3 or more functional groups is also considered as a crosslinking agent. Is preferably 4 or more. Polyols having a functional group number of less than 4 use a large amount of polyols other than the polyol derived from soybean oil of the present invention to increase the crosslinking density, and do not meet the purpose of reducing the environmental burden.

  Further, two or more crosslinking agents may be used in combination. Examples of the crosslinking agent that can be used in the flexible polyurethane foam of the present invention include polyhydric alcohols such as pentaerythritol, diglycerin, dextrose, sorbitol, and sucrose; a polyol obtained by adding an alkylene oxide to the polyhydric alcohols. Monoethanolamine, diethanolamine, ethylenediamine, 3,5-diethyl-2,4 (or 2,6) -diaminotoluene (DETDA), 2-chloro-p-phenylenediamine (CPA), 3,5-bis ( Methylthio) -2,4 (or 2,6) -diaminotoluene, 1-trifluoromethyl-4-chloro-3,5-diaminobenzene, 2,4-toluenediamine, 2,6-toluenediamine, bis (3 , 5-Dimethyl-4-aminophenyl) methane, 4,4 ′ Examples include amine compounds such as -diaminodiphenylmethane, m-xylylenediamine, 1,4-diaminohexane, 1,3-bis (aminomethyl) cyclohexane, and isophoronediamine.

  In the method for producing a flexible polyurethane foam of the present invention, a desired additive can be used in addition to the above-described catalyst, foaming agent, foam stabilizer, and crosslinking agent. Additives include: fillers such as potassium carbonate and barium sulfate; surfactants such as emulsifiers and foam stabilizers; antioxidants such as antioxidants and UV absorbers; flame retardants, colorants, antifungal agents, Examples thereof include conventional additives such as a foam breaker, a dispersant, a discoloration inhibitor, a plasticizer, a solvent, a film-forming aid, a dispersant, and a fragrance.

  As a method for producing the flexible polyurethane foam of the present invention, a cushion for automobile seats can be easily produced by adopting a method (mold method) in which a reactive mixture is injected into a mold and foamed. As a specific reaction method, known methods such as a one-shot method, a semi-prepolymer method, and a prepolymer method can be employed. Moreover, the manufacturing apparatus normally used can be used for flexible polyurethane foam manufacture.

  The flexible polyurethane foam according to the present invention has a rebound resilience of 30% or more, and is therefore used for a cushion for an automobile seat.

  EXAMPLES Hereinafter, although a manufacture example and an Example are shown and this invention is demonstrated further in detail, this invention is not limited to these. In the following examples, parts and% are based on mass unless otherwise specified.

Synthesis of polyol 9 parts by mass of boron trifluoride diethyl ether complex is added to 1200 parts by mass of methanol, and epoxidized soybean oil (the number of epoxy groups described in Table 1 per molecule is maintained while being kept at 25 to 35 ° C. by cooling with stirring. 600 parts by mass) was dropped in 2 hours. The mixture was further stirred at room temperature for 2 hours. Add 27 parts by mass of an adsorbent (Kyowa Chemical Industry Co., Ltd .: KYOWARD 600S), stir for 30 minutes, and filter. A polyol (described in Table 1) was obtained as an oily product.
Table 1 shows the hydroxyl value and yield of the obtained polyol.
In addition, the following compounds were used for the epoxidized soybean oil used.
O-130P: Oxirane oxygen 6.77 mass% Iodine number 2.2
P-ESBO-1: Oxirane oxygen 5.07 mass% Iodine value 36.5
P-ESBO-2: Oxirane oxygen 3.55% by mass Iodine value 69.6

Synthesis of polyether polyol 100 parts by weight of polyol (described in Table 2) and 1.26 parts by weight of potassium hydroxide were charged in a pressure-resistant reaction vessel, heated to 100 ° C. to dissolve potassium hydroxide, and propylene oxide ( Table 2 shows PO) and charged in parts by mass described in Table 2 and reacted for 2 hours. Further, at the same temperature, ethylene oxide (described as EO in Table 2) was charged in the mass part described in Table 2 and reacted for 2 hours. 12.6 parts by mass of an adsorbent (manufactured by Kyowa Chemical Industry Co., Ltd .: KYOWARD 600S) was added, stirred for 1 hour, filtered, and the filtrate was heated to 100 ° C / 10 mmHg under reduced pressure to give a pale yellow oil. A polyether polyol (described in Table 2) was obtained.
Table 2 shows the hydroxyl value and yield of the polyether polyol obtained and the abbreviations used in the examples. Table 2 shows the number average molecular weight as the molecular weight of the alkylene oxide used from the yield as a total amount added.

Production of flexible polyurethane foam To 100 parts by mass of the obtained polyether polyol, 0.17 parts by mass of an amine catalyst (Daboco33LV: Sankyo Air Products), tin-based catalyst (BT-11: manufactured by Asahi Denka Kogyo Co., Ltd.) 0 .17 parts by mass, 1.4 parts by mass of a silicone-based foam stabilizer (SH-192: manufactured by Toray Dow Corning) and 4 parts by mass of water were mixed at room temperature. Further, a polyisocyanate (described in Table 3) blended in an amount of 5 mol% with respect to active hydrogen was added and stirred with a homomixer, then poured into a 70 mm × 350 mm × 350 mm mold, and the lower mold temperature Foaming was carried out at 55 ° C. for 20 minutes to obtain a flexible polyurethane foam. The rebound resilience of the obtained flexible polyurethane foam was measured according to JIS K 6400. The results are shown in Table 3.

The polyisocyanate used was
Crude MDI: Poly (diphenylmethane-4,4'-diisocyanate)
Degree of polymerization 2.8
TDI-80: manufactured by Nippon Polyurethane Industry Co., Ltd., 2,4-tolylene diiso
Mixing cyanate with 2,6-tolylene diisocyanate
Things (80:20)

  As is clear from Examples 1-1 to 1-10, when a polyether polyol in which propylene oxide and ethylene oxide are added in the proportions described in the claims of the present invention is used, the rebound resilience is 30%. On the other hand, in the comparative example, when the polyether polyol added with only propylene oxide was used, the rebound resilience was less than 30%, so the molar ratio of propylene oxide and ethylene oxide added was selected. It is clear that a flexible polyurethane foam which can be used for a cushion for an automobile seat excellent in rebound resilience can be produced.

  Polyether polyols using epoxidized soybean oil having 2.1 epoxy groups per molecule were compared with Examples 1-1 and 1-2 having the same molecular weight, and thus the rebound resilience was low. It is clear that it is preferable to use polyols having 3 to 4 groups.

  When the number of the epoxy groups of the raw material is the same, it is clear that a higher molecular weight is preferable from the comparison of Examples 1-3, 1-6, and 1-7.

Claims (4)

  An automobile comprising a flexible polyurethane foam obtained from a polyol and a polyisocyanate compound obtained by adding an alkylene oxide to an epoxidized soybean oil ring-opened with an alcohol in a molar ratio of ethylene oxide / propylene oxide = 20/80 to 5/95 Seat cushion.   The cushion for an automobile seat according to claim 1, wherein the alcohol is methanol.   The automobile seat cushion according to claim 1 or 2, wherein water is used as a foaming agent. The number average molecular weight of a polyol is 1500-8000, The cushion for motor vehicle seats in any one of Claims 1-3.