JP2018204030A - Polyurethane elastomer forming composition using industrial mechanical component member, and industrial mechanical component using the same - Google Patents

Abstract

To provide a thermosetting polyurethane elastomer forming composition for industrial mechanical component member short in molding time, having no unreacted foreign article in a cured article, strong and high in mechanical strength, and a member for industrial mechanical component using the composition.SOLUTION: By containing a phosphoric acid ester compound having at least one or more ethylene oxide in a substituent skeleton as a reaction inhibitor (C) in an isocyanate group terminated urethane prepolymer of a thermosetting polyurethane elastomer forming composition for industrial mechanical component member, a thermosetting polyurethane elastomer for industrial mechanical component short in molding cycle, having no generation of unreacted foreign article in a molded article, high in mechanical strength and strong can be obtained without deteriorating properties of the isocyanate group terminated urethane prepolymer.SELECTED DRAWING: None

Description

The present invention relates to a thermosetting polyurethane elastomer-forming composition used for industrial machine component parts.

Thermosetting polyurethane elastomers have very high durability because they have high modulus, high breaking strength, low wear, and low strain, and are widely and suitably used as component parts for industrial machines.

A thermosetting polyurethane elastomer generally used for industrial equipment parts is a mixture obtained by mixing a main agent composed of an isocyanate component and a curing agent composed of an active hydrogen-containing component with a mixing head of a casting machine. Can be injected into a mold, and the mixed solution can be heated and cured (urethane reaction) in the mold.

Here, as a component forming a composition for molding a thermosetting polyurethane elastomer, an isocyanate group-terminated urethane prepolymer (A) (hereinafter abbreviated as “NCO group-terminated urethane prepolymer”) composed of an isocyanate and a polyol, and A method is generally used in which a hydroxyl group terminal curing agent (B) made of a polyol (hereinafter abbreviated as “OH group terminal curing agent”) is mixed and cured by heating.

For example, an NCO group-terminated urethane prepolymer composed of diphenyl metadiisocyanate (hereinafter abbreviated as “MDI”) as an isocyanate component, polybutylene adipate (hereinafter abbreviated as “PBA”) as a polyol, and 1,4- An OH group terminal curing agent in which butanediol, trimethylolpropane and PBA are mixed is suitably used.

When the NCO group-terminated urethane prelimer (A) is produced, phosphoric acid is used for the purpose of suppressing side reactions during synthesis, suppressing coloring, and improving the storage stability of the obtained NCO group-terminated urethane prelimer (A). It is produced by adding an acidic compound such as a compound as a reaction inhibitor (C) (see, for example, Patent Documents 1 to 4).

In recent years, since the cost reduction of industrial machine parts is required, the molding cycle has been shortened. This not only improves productivity, but also reduces energy costs. In addition, since the rotation cycle of the mold is shortened, the number of molds can be reduced, so that the capital investment cost can be suppressed.

From the above circumstances, a nurating catalyst (D1) and an allophanating catalyst (D2) are used as the catalyst (D) for shortening the molding cycle. Moreover, in order to improve the mechanical strength of the resulting thermosetting polyurethane elastomer, a method of molding with an excess of isocyanate group (hydroxyl group / isocyanate group = 0.3 to 0.8 (molar ratio)) is used (for example, (See Patent Documents 5 to 7).

In particular, a formulation using a nurating catalyst (D1) such as potassium acetate or a quaternary ammonium salt is preferably used because of easy control of reaction and mechanical strength.

Japanese Patent Laid-Open No. 49-75505 JP-A-57-82358 JP-A-7-173240 JP-A-8-231669 Japanese Patent Laid-Open No. 2002-20445 JP-A-2005-314502 JP 2009-227875 A

However, the NCO group-terminated urethane prepolymer (A) that is excessively blended in these prescriptions may not be locally nurated or allophanatized during the heat curing process, and is very small. Unreacted NCO-terminated prepolymer (A) remains as an unreacted foreign substance in the molded product, and the mechanical strength is lowered from this portion, causing breakage and the like. Yes.

The present invention has been made based on the above circumstances, and the NCO group-terminated urethane prepolymer (A) of the thermosetting polyurethane elastomer-forming composition for industrial machine component members is used as the reaction inhibitor (C). By including 5 to 600 ppm of a phosphate ester compound having at least one ethylene oxide in the substituent skeleton, the molding cycle is short and the occurrence of unreacted foreign matter in the molded product without impairing the properties of the prepolymer. It is an object of the present invention to provide a thermosetting polyurethane elastomer for industrial machine parts having high mechanical strength and high strength.

The present invention is shown in the following (1) to (4).
(1) In a thermosetting polyurethane elastomer-forming composition for industrial machine parts comprising at least an NCO group-terminated urethane prepolymer (A) and an OH group-terminated curing agent (B), the NCO group-terminated urethane prepolymer (A) is The reaction inhibitor (C) is characterized by containing 5 to 600 ppm of a phosphate ester compound having at least one ethylene oxide in the substituent skeleton.
(2) The OH group terminal curing agent (B) described in the above (1) includes at least a polyurethane nurating catalyst (D1) and / or a polyurethane allophanating catalyst (D2) as the catalyst (D). It is characterized by.
(3) The mixing ratio (functional group ratio) of the NCO group-terminated urethane prepolymer (A) and the OH group-terminal curing agent (B) according to any one of (1) or (2) is a hydroxyl group / isocyanate. Group (hereinafter abbreviated as “α value”) = 0.2 to 0.8 (molar ratio).
(4) The JIS-A hardness of the industrial machine component member obtained by heat-curing the thermosetting polyurethane elastomer-forming composition for industrial machine components according to any one of (1) to (3) is 60. It is the range of -95.

By using the thermosetting polyurethane elastomer-forming composition for industrial machine parts of the present invention for industrial machines, there is no unreacted foreign matter in the molded product, which could not be achieved in the past, and the properties of the NCO-terminated urethane prepolymer Thus, a thermosetting polyurethane elastomer for industrial machine parts having a short molding cycle and a strong strength can be obtained.

In the thermosetting polyurethane elastomer-forming composition for industrial machine parts of the present invention, at least one NCO group-terminated urethane prepolymer (A) as a reaction inhibitor (C) contains at least one ethylene oxide in the substituent skeleton. It is characterized in that it contains 5 to 600 ppm of a phosphoric acid ester compound. Thus, by using a phosphate ester compound having one or more ethylene oxides in the substituent skeleton, the resulting NCO group-terminated urethane prepolymer (A) suppresses side reactions during production and stock storage. And an NCO group-terminated urethane prepolymer (A) having a low viscosity and very low coloration and a low number of colors. When the amount of phosphate ester compound having one or more ethylene oxide in the substituent skeleton is 5 ppm or less, an NCO-terminated urethane prepolymer with a high viscosity and a very high number of colors can be obtained and used in terms of quality. Is difficult. In addition, this NCO group-terminated urethane prepolymer (A) is used in order to shorten the molding cycle that has been carried out in recent years, and a formulation in which a nurating catalyst (D1) or an allophanating catalyst (D2) is introduced as a catalyst (D). In the industrial machine part of the thermosetting polyurethane elastomer obtained in the above, the NCO group-terminated urethane prepolymer (A) blended excessively reacts, and a uniform and tough cured product free from unreacted foreign matters can be obtained. When a reaction inhibitor other than the phosphoric acid ester compound having one or more ethylene oxides in the substituent skeleton is used, the excessively blended NCO group-terminated urethane prepolymer (A) does not react cleanly. Unreacted foreign matter is generated, resulting in a non-uniform and weak cured product. In addition, when the addition amount of the phosphate ester compound having one or more ethylene oxides in the substituent skeleton is 600 ppm or more, the reaction balance with the catalyst (D) added to the OH group terminal curing agent is lost, and thermosetting is performed. The reaction does not proceed sufficiently during processing, and the molding cycle cannot be shortened.
The phosphate ester compound having one or more ethylene oxides in the substituent skeleton used as the reaction inhibitor (C) used in the present invention is not particularly limited as long as the effects of the present invention are exhibited, but examples As general formulas 1-3.

一般式１〜３の具体例として、ｎ、ｍ、ｌ＝１〜１００であり、Ｒ₁、Ｒ₂、Ｒ₃は炭素数１〜６０の直鎖、分岐、又は環状の飽和又は不飽和アルキルがよく、特に好ましくはｎ、ｍ、ｌ＝１〜３０であり、Ｒ₁、Ｒ₂、Ｒ₃は炭素数６〜３０の直鎖、分岐、又は環状の飽和又は不飽和アルキル（フェニル基を含む）である。ｎ、ｍ、ｌの数及びＲ₁、Ｒ₂、Ｒ₃の構造は同一であっても、異なっていても良い。市販化されている具体例として、ジ（Ｃ１２−１５）パレス−２リン酸「ＮＩＫＫＯＬ ＤＤＰ−２ 日光ケミカルズ社製」、ジ（Ｃ１２−１５）−パレス４リン酸「ＮＩＫＫＯＬ ＤＤＰ−４ 日光ケミカルズ社製」、ジ（Ｃ１２−１５）−パレス６リン酸「ＮＩＫＫＯＬ ＤＤＰ−６ 日光ケミカルズ社製」、ジ（Ｃ１２−１５）−パレス８リン酸「ＮＩＫＫＯＬ ＤＤＰ−８ 日光ケミカルズ社製」、ジ（Ｃ１２−１５）−パレス１０リン酸「ＮＩＫＫＯＬ ＤＤＰ−１０ 日光ケミカルズ社製」、リン酸（モノ，ジ）ポリエチレングルコール（５ＥＯ）Ｃ１０−１２アルコール「Ｐｈｏｓｐｈｏｌａｎ ＰＳ−２３６ Ａｋｚｏ Ｎｐｂｅ社製」、リン酸（モノ，ジ）ポリエチレングルコール（３ＥＯ）Ｃ１０−１５アルコール「Ｐｈｏｓｐｈｏｌａｎ ＰＳ−２２２ Ａｋｚｏ Ｎｐｂｅ社製」、リン酸（モノ，ジ）Ｃ１０−１４アルコール−３−エトキシレート「Ｐｈｏｓｐｈｏｌａｎ ＰＳ−２２０ Ａｋｚｏ Ｎｐｂｅｌ社製」、リン酸（モノ，ジ）ポリエチレングルコール（６ＥＯ）＋トリデカノール「Ｐｈｏｓｐｈｏｌａｎ ＰＳ−１３１ Ａｋｚｏ Ｎｐｂｅ社製」、ポリオキシエチレントリデシルエーテルリン酸エステル「プライサーフ Ａ２１２Ｃ、プライサーフ Ａ２１５Ｃ 第一工業製薬社製」、ポリオキシエチレンアルキル（C８）リン酸エステル「プライサーフ Ａ２０８Ｆ、プライサーフ Ａ２１５C 第一工業製薬社製」、ポリオキシエチレンアルキル（C１２、１３）リン酸エステル「プライサーフ Ａ２０８Ｍ、プライサーフ Ａ２１５C 第一工業製薬社製」、ポリオキシエチレンラウリルエーテルリン酸エステル「プライサーフ Ａ２０８Ｂ、プライサーフ Ａ２１９Ｂ 第一工業製薬社製」、ポリオキシエチレンアルキル（Ｃ１０）エーテルリン酸エステル「プライサーフ Ａ２１０Ｄ 第一工業製薬社製」、ポリオキシエチレンスチレン化フェニルエーテルリン酸エステル「プライサーフ ＡＬ、プライサーフ ＡＬ１２Ｈ 第一工業製薬社製」、リン酸（モノ，ジ）ポリエチレングリコール（４Ｅ０）４−ノニフェニル「試薬 東京化成工業社製」、トリ（Ｃ１２−１５）パレス−２リン酸「ＮＩＫＫＯＬ ＴＤＰ−２ 日光ケミカルズ社製」、トリ（Ｃ１２−１５）パレス−４リン酸「ＮＩＫＫＯＬ ＴＤＰ−４ 日光ケミカルズ社製」、トリ（Ｃ１２−１５）パレス−６リン酸「ＮＩＫＫＯＬ ＴＤＰ−６ 日光ケミカルズ社製」、トリ（Ｃ１２−１５）パレス−８リン酸「ＮＩＫＫＯＬ ＴＤＰ−８ 日光ケミカルズ社製」、トリ（Ｃ１２−１５）パレス−１０リン酸「ＮＩＫＫＯＬ ＴＤＰ−１０ 日光ケミカルズ社製」、ホスフェートポリエーテルエステル「ＴＲＩＴＯＮ Ｈ−５５、Ｈ−６６、ＱＳ−４４、ＸＱＳ−２０ ダウサーファクタンツ社製」等が挙げられる。

As specific examples of general formulas 1 to 3, n, m, and l = 1 to 100, and R ₁ , R ₂ , and R ₃ are linear, branched, or cyclic saturated or unsaturated alkyl having 1 to 60 carbon atoms. And particularly preferably n, m and l = 1 to 30, and R ₁ , R ₂ and R ₃ are each a straight chain, branched or cyclic saturated or unsaturated alkyl having 6 to 30 carbon atoms (with a phenyl group). Included). The number of n, m and l and the structures of R ₁ , R ₂ and R ₃ may be the same or different. As specific examples that are commercially available, di (C12-15) Palace-2 phosphate “NIKKOL DDP-2 manufactured by Nikko Chemicals”, Di (C12-15) -Palace 4 phosphate “NIKKOL DDP-4 Nikko Chemicals” Di (C12-15) -Palace 6-phosphate "NIKKOL DDP-6 made by Nikko Chemicals", Di (C12-15) -Palace 8-phosphate "NIKKOL DDP-8 made by Nikko Chemicals", di (C12 -15) -Palace 10 phosphoric acid “NIKKOL DDP-10 manufactured by Nikko Chemicals”, phosphoric acid (mono, di) polyethylene glycol (5EO) C10-12 alcohol “Phosphoran PS-236 manufactured by Akzo Npbe”, phosphoric acid ( Mono, di) polyethylene glycol (3EO) C10-15 alcohol “Phospholan” PS-222 Akzo Npbe ", phosphoric acid (mono, di) C10-14 alcohol-3-ethoxylate" Phosphoran PS-220 Akzo Npbel ", phosphoric acid (mono, di) polyethylene glycol (6EO) + Tridecanol “Phosphoran PS-131 Akzo Npbe”, polyoxyethylene tridecyl ether phosphate “Plysurf A212C, Plysurf A215C Daiichi Kogyo Seiyaku”, polyoxyethylene alkyl (C8) phosphate “Plysurf” A208F, Plysurf A215C, manufactured by Daiichi Kogyo Seiyaku ", polyoxyethylene alkyl (C12, 13) phosphate ester" Plysurf A208M, Plysurf A215C, manufactured by Daiichi Kogyo Seiyaku ", polyoxyethylene laur Ryl ether phosphate "Plysurf A208B, Plysurf A219B, manufactured by Daiichi Kogyo Seiyaku", polyoxyethylene alkyl (C10) ether phosphate ester "Plysurf A210D, manufactured by Daiichi Kogyo Seiyaku", polyoxyethylene styrenated phenyl Ether phosphate ester "Plysurf AL, Plysurf AL12H, manufactured by Daiichi Kogyo Seiyaku", phosphoric acid (mono, di) polyethylene glycol (4E0) 4-noniphenyl "Reagent, manufactured by Tokyo Chemical Industry Co., Ltd.", Tri (C12-15) Palace-2 Phosphate “NIKKOL TDP-2 Nikko Chemicals”, Tri (C12-15) Palace-4 Phosphate “NIKKOL TDP-4 Nikko Chemicals”, Tri (C12-15) Palace-6 Phosphate “ NIKKOL TDP-6 made by Nikko Chemicals " (C12-15) Palace-8 phosphate “NIKKOL TDP-8 manufactured by Nikko Chemicals”, Tri (C12-15) Palace-10 phosphate “NIKKOL TDP-10 manufactured by Nikko Chemicals”, phosphate polyether ester “TRITON H -55, H-66, QS-44, XQS-20 manufactured by Dowser Factors ".

The NCO group-terminated urethane prepolymer (A) used in the present invention can be obtained by a urethanization reaction of at least a polyisocyanate (A1) and a polyol (A2) using a reaction inhibitor (C). Further, the NCO content of the NCO group-terminated urethane prepolymer (A) is preferably 5 to 25% by mass. When the NCO content is lower than 5% by mass, the viscosity of the prepolymer is mainly increased, and the flowability of the urethane resin is significantly deteriorated during casting. If it is higher than 25% by mass, the stability of properties during storage and use will be significantly deteriorated, and it will be difficult to obtain stable industrial machine parts, resulting in molding defects. It will become unsuitable as a terminal urethane prepolymer.

The NCO group-terminated urethane prepolymer (A) is prepared by adding and stirring the polyisocyanate (A1) and the reaction inhibitor (C) in a stirring vessel, and then maintaining the temperature in the stirring vessel at 40 to 70 ° C. ) Is stirred. Then, NCO group terminal urethane prepolymer (A) can be obtained by advancing urethanation reaction for about 2 to 5 hours, keeping the temperature in a stirring container at 70-90 degreeC.

The polyisocyanate (A1) used in the present invention is not particularly limited as long as the effects of the present invention are exhibited, but at least one kind is preferably selected from aromatic diisocyanates from the viewpoint of mechanical properties and reaction control. 4,4'-diphenylmethane diisocyanate is particularly preferred.

<Polyisocyanate>
Specific examples of the polyisocyanate (A1) include hexamethylene diisocyanate, lysine diisocyanate, isophorone diisocyanate, cyclohexyl diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, hydrogenated xylylene diisocyanate, hydrogenated trimethylxylylene diisocyanate, 2-methylpentane- 1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, 2,2,4-trimethylhexahylene-1,6-diisocyanate, 2,4,4-trimethylhexahylene-1,6-diisocyanate Aliphatic and alicyclic diisocyanates such as 4,4'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl diisocyanate, 1,5-naphthylene diisocyanate Aromatic diisocyanates such as paraphenylene diisocyanate, tolylene-2,4-diisocyanate, tolylene-2,6-diisocyanate. Difficult yellowing diisocyanates such as orthoxylylene diisocyanate, metaxylylene diisocyanate, paraxylylene diisocyanate, tetramethylxylylene diisocyanate. In addition, urethane-modified products, urea-modified products, carbodiimide-modified products, uretonimine-modified products, uretdione-modified products, isocyanurate-modified products, allophanate-modified products, etc. can be used.

The polyol (A2) used in the present invention is not particularly limited as long as the effects of the present invention are exhibited, but from the viewpoint of mechanical properties and glass transition temperature, the number of average functional groups is 2 to 3, and the number average molecular weight is 250 to 5000. It is preferable that at least one selected from the following polyester polyols, polyether polyols, and polycarbonate polyols. In addition, a monomer polyol can also be used together as needed.

<Polyester polyol>
Specific examples of polyester polyols include phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, glutaconic acid, azelaic acid, Dicarboxylic acids such as sebacic acid, 1,4-cyclohexyl dicarboxylic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α, β-diethylsuccinic acid, maleic acid, fumaric acid, etc. Or one or more of these anhydrides and the like, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1, -Nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, One or more low molecular weight polyols having a molecular weight of 500 or less, such as dimer acid diol, bisphenol A ethylene oxide and propylene oxide adducts, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, pentaerythritol And those obtained from the polycondensation reaction. In addition, a polyester-amide polyol obtained by replacing a part of the low molecular polyol with a low molecular polyamine such as hexamethylene diamine, isophorone diamine or monoethanolamine or a low molecular amino alcohol can also be used.

<Polyether polyol>
Specific examples of the polyether polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, , 5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene Glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, penta Small molecules such as erythritol Initiates compounds having 2 or more, preferably 2-3 active hydrogen groups such as diols or low molecular weight polyamines such as ethylenediamine, propylenediamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, xylylenediamine, etc. As an agent, polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, etc., or alkyl glycidyl ethers such as methyl glycidyl ether, aryl glycidyl ethers such as phenyl glycidyl ether And polyether polyols obtained by ring-opening polymerization of cyclic ether monomers such as tetrahydrofuran.

<Polycarbonate polyol>
Specific examples of the polycarbonate polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neo Pentyl glycol, diethylene glycol, dipropylene glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide and propylene oxide adducts of bisphenol A, bis (β-hydroxyethyl) benze One or more low-molecular polyols such as xylylene glycol, glycerin, trimethylolpropane, pentaerythritol, dialkyl carbonates such as dimethyl carbonate and diethyl carbonate, alkylene carbonates such as ethylene carbonate and propylene carbonate, diphenyl carbonate, di Examples thereof include those obtained from a dealcoholization reaction or a dephenol reaction with diaryl carbonates such as naphthyl carbonate, dianthryl carbonate, diphenanthryl carbonate, diindanyl carbonate, and tetrahydronaphthyl carbonate.

<Monomer polyol>
Specific examples of the monomer polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, and 1,5-pentane. Diol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neopentyl Examples include glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, and pentaerythritol. It is done.

In addition, the polyol (B) includes a polyolefin polyol, an acrylic polyol, a (meth) acrylic acid ester, a (meth) acrylic acid hydroxy compound, a silicone polyol, a castor oil-based polyol, and a fluorine-based polyol as long as the performance does not deteriorate. , Or two or more can be used in combination.

<Polyolefin polyol>
Specific examples of the polyolefin polyol include polybutadiene having two or more hydroxyl groups, hydrogenated polybutadiene, polyisoprene, hydrogenated polyisoprene and the like.

<Acrylic polyol>
Examples of the acrylic polyol include acrylic acid ester and / or methacrylic acid ester (hereinafter referred to as (meth) acrylic acid ester), acrylic acid hydroxy compound and / or methacrylic acid having at least one hydroxyl group in the molecule that can be a reaction point. Examples thereof include those obtained by copolymerizing an acrylic monomer using a thermal compound, a light energy such as an ultraviolet ray or an electron beam, and the like with a hydroxy compound (hereinafter referred to as a (meth) acrylic acid hydroxy compound) and a polymerization initiator.

<(Meth) acrylic acid ester>
Specific examples of (meth) acrylic acid esters include alkyl esters having 1 to 20 carbon atoms. Specific examples of such (meth) acrylate esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, (Meth) such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate Alkyl acrylates, esters of (meth) acrylic acid with cycloaliphatic alcohols such as cyclohexyl (meth) acrylate, phenyl (meth) acrylate, (meth) acrylic acid allyl esters such as benzyl (meth) acrylate Can be mentioned. Such (meth) acrylic acid esters can be used singly or in combination of two or more.

<(Meth) acrylic acid hydroxy compound>
Specific examples of the (meth) acrylic acid hydroxy compound have at least one hydroxyl group in the molecule that can be a reaction point with the polyisocyanate composition. Specifically, 2-hydroxyethyl acrylate, 2 -Hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 3-hydroxy-2,2-dimethylpropyl acrylate, and acrylic acid hydroxy compounds such as pentaerythritol triacrylate. Moreover, methacrylic acid hydroxy compounds, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 3-hydroxy-2,2-dimethylpropyl methacrylate, and pentaerythritol trimethacrylate, are mentioned. These acrylic acid hydroxy compounds and / or methacrylic acid hydroxy compounds can be used singly or in combination of two or more.

<Polymerization initiator>
Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator, and are appropriately selected depending on the polymerization method.
Specific examples of the thermal polymerization initiator include peroxydicarbonates such as di-2-ethylhexyl peroxydicarbonate, t-butylperoxybenzoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisopropyl carbonate, Peroxyesters such as t-hexylperoxyisopropyl carbonate, di (t-butylperoxy) -2-methylcyclohexane, di (t-butylperoxy) 3,3,5-trimethylcyclohexane and di (t-butylperoxy) cyclohexane Peroxyketals and the like.
Specific examples of the photopolymerization initiator include acetophenone, methoxyacetophenone, 2,2-diethoxyacetophenone, p-dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, α-hydroxy-α, α ′. -Acetophenones such as dimethylacetophenone, 2-hydroxy-2-cyclohexylacetophenone, 2-methyl-1 [4- (methylthio) phenyl] -2-montforinopropanone-1, benzoin, benzoin methyl ether, benzoin ethyl ether Benzoin ethers such as benzoin isopropyl butyl ether, benzophenone, 2-chlorobenzophenone, p, p'-dichlorobenzophenone, N, N'-tetramethyl-4,4'-diaminobenzophenone, 4- (2-hydroxy Ketones such as ethoxy) phenyl (2-hydroxy-2-propyl) ketone, thioxanthones such as thioxanthone, 2-chlorothioxanthone, 2-methylthioxanthone, phosphine oxides such as bisacylphosphine oxide and benzoylphosphine oxide And ketals such as benzyldimethyl ketal and quinones such as camphan-2,3-dione and phenanthrenequinone.

<Silicone polyol>
Specific examples of the silicone polyol include a vinyl group-containing silicone compound obtained by polymerizing γ-methacryloxypropyltrimethoxysilane and the like, and α, ω-dihydroxypolydimethylsiloxane having at least one terminal hydroxyl group in the molecule, α, Mention may be made of polysiloxanes such as ω-dihydroxypolydiphenylsiloxane.

<Castor oil-based polyol>
Specific examples of the castor oil-based polyol include linear or branched polyester polyols obtained by a reaction between a castor oil fatty acid and a polyol. Dehydrated castor oil, partially dehydrated castor oil partially dehydrated, and hydrogenated castor oil added with hydrogen can also be used.

<Fluorine-based polyol>
A specific example of the fluorine-based polyol is a linear or branched polyol obtained by a copolymerization reaction using a fluorine-containing monomer and a monomer having a hydroxy group as essential components. Here, the fluorine-containing monomer is preferably a fluoroolefin, for example, tetrafluoroethylene, chlorotrifluoroethylene, trichlorofluoroethylene, hexafluoropropylene, vinylidene fluoride, vinyl fluoride, trifluoromethyl trifluoroethylene. Is mentioned. Examples of the monomer having a hydroxyl group include hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and cyclohexanediol monovinyl ether, hydroxyalkyl allyl ethers such as 2-hydroxyethyl allyl ether, and hydroxyalkyl vinyl crotonates. And monomers having a hydroxyl group such as a hydroxyl group-containing vinyl carboxylate or an allyl ester.

The above-mentioned polyol (A2) can be used for the OH group terminal curing agent (B) used in the present invention, but it is not particularly limited as long as the effects of the present invention are exhibited. From the viewpoint of improving mechanical properties and molding processability, monomer polyols can be used alone or in admixture of two or more. Further, a mixture obtained by adding any one of polyester polyols, polyether polyols, and polycarbonate polyols having an average functional group number of 2 to 3 and a number average molecular weight of 250 to 5000 can be used. As the monomer polyol, a mixture of 1,4-butanediol and trimethylolpropane is preferable. Further, a mixture obtained by adding a polyester polyol or polyether polyol having an average number of functional groups of 2 and an average molecular weight of 500 to 3000 is preferable.

The polyurethane nurating catalyst (D1) and the polyurethane allophanating catalyst (D2) used as the catalyst (D) for use in the present invention are not particularly limited as long as the effects of the invention are exerted. From the viewpoint of improving the mechanical properties and molding processability, potassium salts and quaternary ammonium salts are preferable as the polyurethane nurating catalyst (D1), and N, N, N′-trimethyl is used as the polyurethane allophanating catalyst (D2). Aminoethylethanolamine and N, N-dimethylaminoethoxyethanol are preferred. In addition, as a urethanization catalyst for promoting the urethanization reaction, an amine catalyst such as triethylenediamine, an imidazole catalyst such as 1-isobutyl-2-methylimidazole, a metal catalyst such as dioctyltin dilaurate, etc. It can also be used together.

<Nuration catalyst for polyurethane>
The polyurethane nurating catalyst (D1) used in the nurating reaction can be appropriately selected from known catalysts, and specific examples thereof include triethylamine, N-ethylpiperidine, N, N′-dimethylpiperazine. N-ethylmorpholine, tertiary amines such as phenolic Mannich base, tetramethylammonium bicarbonate, methyltriethylammonium bicarbonate, ethyltrimethylammonium bicarbonate, propyltrimethylammonium bicarbonate, butyltrimethylammonium Bicarbonate, pentyltrimethylammonium bicarbonate, hexyltrimethylammonium bicarbonate, heptyltrimethylammonium bicarbonate, octyltrimethylammonium bicarbonate, nonyltrimethylammonium Bicarbonate, decyltrimethylammonium bicarbonate, undecyltrimethylammonium bicarbonate, dodecyltrimethylammonium bicarbonate, tridecyltrimethylammonium bicarbonate, tetradecyltrimethylammonium bicarbonate, heptadecyltrimethylammonium bicarbonate Hexadecyltrimethylammonium hydrogencarbonate, heptadecyltrimethylammonium hydrogencarbonate, octadecyltrimethylammonium hydrogencarbonate, (2-hydroxypropyl) trimethylammonium hydrogencarbonate, hydroxyethyltrimethylammonium hydrogencarbonate, 1-methyl-1- Such as azania-4-azabicyclo [2,2,2] octanium bicarbonate or 1,1-dimethyl-4-methylpiperidinium bicarbonate Quaternary ammonium bicarbonate, tetramethylammonium carbonate, methyltriethylammonium carbonate, ethyltrimethylammonium carbonate, propyltrimethylammonium carbonate, butyltrimethylammonium carbonate, pentyltrimethylammonium carbonate, hexyltrimethylammonium carbonate, heptyl Trimethylammonium carbonate, octyltrimethylammonium carbonate, nonyltrimethylammonium carbonate, decyltrimethylammonium carbonate, undecyltrimethylammonium carbonate, dodecyltrimethylammonium carbonate, tridecyltrimethylammonium carbonate, tetradecyltrimethylammonium carbonate, Heptadecyltrimethylammonium carbonate, hexadecyltrimethylammonium Carbonate, heptadecyltrimethylammonium carbonate, octadecyltrimethylammonium carbonate, (2-hydroxypropyl) trimethylammonium carbonate, hydroxyethyltrimethylammonium carbonate, 1-methyl-1-azania-4-azabicyclo [2,2, 2] of octanium carbonate or quaternary ammonium carbonate such as 1,1-dimethyl-4-methylpiperidinium carbonate, hydroxyalkylammonium such as trimethylhydroxypropylammonium, trimethylhydroxypropylammonium, triethylhydroxyethylammonium Alkali metal salts of carboxylic acids such as hydroxide, weak organic acid salts, acetic acid, propionic acid, butyric acid, caproic acid, capric acid, valeric acid, octylic acid, myristic acid, naphthenic acid And the like. Moreover, these isocyanurate-ized catalysts (D1) for polyurethane can be used individually or in combination of 2 or more types. The amount of the isocyanurate-forming catalyst (D1) used is in the range of 0.001 to 0.5 mass% with respect to the total weight of the NCO group-terminated urethane prepolymer (A) and the OH group-end curing agent (B). In particular, from the viewpoint of easy reaction control, it is more preferably used in the range of 0.005 to 0.10% by mass.

<Allophanatization catalyst for polyurethane>
The allophanatization catalyst for polyurethane (D2) used in the allophanatization reaction can be appropriately selected from known catalysts, and for example, a metal salt of a carboxylic acid can be used.
Specific examples of the carboxylic acid include acetic acid, propionic acid, butyric acid, caproic acid, octylic acid, lauric acid, myristic acid, palmitic acid, stearic acid, 2-ethylhexanoic acid and other saturated aliphatic carboxylic acids, cyclohexanecarboxylic acid, Saturated monocyclic carboxylic acids such as cyclopentanecarboxylic acid, saturated polycyclic carboxylic acids such as bicyclo (4.4.0) decane-2-carboxylic acid, mixtures of the above carboxylic acids such as naphthenic acid, oleic acid, linoleic acid , Monocarboxylic acids such as linolenic acid, soybean fatty acid, unsaturated fatty carboxylic acid such as tall oil fatty acid, aromatic aliphatic carboxylic acid such as diphenylacetic acid, aromatic carboxylic acid such as benzoic acid and toluic acid; phthalic acid, Isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid Adipic acid, pimelic acid, suberic acid, kurtaconic acid, azelaic acid, sebacic acid, 1,4-cyclohexyldicarboxylic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α, and polycarboxylic acids such as β-diethylsuccinic acid, maleic acid, fumaric acid, trimellitic acid, and pyromellitic acid.

In addition, as the metal constituting the metal salt of carboxylic acid, alkali metals such as lithium, sodium and potassium, alkaline earth metals such as magnesium, calcium and barium, other typical metals such as tin and lead, manganese, iron, Examples include transition metals such as cobalt, nickel, copper, zinc, and zirconium. These carboxylic acid metal salts can be used alone or in combination of two or more.

In addition, examples of the alkanolamine include N, N, N′-trimethylaminoethylethanolamine, N, N-dimethylaminoethoxyethanol and the like. In addition, the usage-amount of an allophanatization catalyst (D2) is 0.001-0.5 mass% with respect to the total weight of NCO group terminal urethane prepolymer (A) and OH group terminal hardening | curing agent (B). It is preferable to use it, and it is more preferable to use in the range of 0.005-0.10 mass% especially from a viewpoint of the ease of reaction control.

In the present invention, if necessary, an antioxidant, a defoaming agent, an ultraviolet absorber and the like can be introduced and used as an additive in the forming composition.

In the present invention, using the thermosetting polyurethane elastomer-forming composition described so far, a curing process (specifically, a process for promoting curing by heating) is performed in a mold as a process. To produce a thermoset polyurethane elastomer molded article having urethanization, nuration, and allophanate bonds.

In this case, as a method for producing a thermosetting polyurethane elastomer molded product using the forming composition according to the present invention, it is preferable to produce by a method including the following steps.
Step (1):
NCO group-terminated prepolymer (A) and hydroxyl-terminated curing agent (B), except that the catalyst (D) is not added to the hydroxyl-terminated curing agent (B) in advance. To form a composition. In addition, when air is involved and bubbles are observed, the bubbles are removed by vacuum defoaming or the like. These steps are preferably performed using a dedicated polyurethane casting machine.
Step (2):
Immediately after mixing the moldable composition into a preheated mold (injection), the moldable composition is cured in the mold (specifically, heated to cause a curing reaction). ). In this case, the temperature of the mold is preferably in the range of 80 to 170 ° C. from the viewpoint that the urethanization reaction, the uretization, and the allophanatization reaction proceed easily and reliably.
Step (3):
After the forming composition is cured, the cured product (that is, the thermosetting polyurethane elastomer molded product) is taken out from the mold (demolding). In the present invention, the time required from casting to demolding is not particularly limited. However, from the viewpoint of productivity of the thermosetting polyurethane elastomer intended by the present invention, the amount of catalyst and molding It is preferable that the preheating temperature of the mold is adjusted to be in the range of 30 to 600 seconds.
Step (4):
After demolding the thermosetting polyurethane elastomer molding (industrial machine part), aging treatment is performed at room temperature for one week.

In addition, the molar ratio of the NCO group content of the NCO group-terminated prepolymer and the OH group content of the OH group-terminated curing agent at the time of casting is α value = 0.2 to 0.8 (molar ratio). 3 to 0.7 is particularly preferable. When it is less than 0.2, nurateization or allophanate formation with excess isocyanate becomes extremely large, and it is difficult to suppress the generation of unreacted substances in the molded product, and the tensile property value is remarkably increased due to an increase in the number of crosslinking points. Cause a decline. On the other hand, if it exceeds 0.8, the number of cross-linking points due to nurateization or allophanate decreases, leading to a decrease in the initial modulus (stress at 100% elongation), insufficient strength at each hardness, and large deformation. It will become nothing.

The present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not limited thereto. In Examples and Comparative Examples, “%” means “% by mass”.

Examples 1-7, Comparative Examples 1-6
In the mixing ratio shown in Table 1, various polyisocyanates (A1), various reaction inhibitors (C), and antioxidants were charged and stirred into a 5 L stirring vessel filled with nitrogen. Thereafter, various polyols (A2) were charged and stirred while maintaining the temperature in the stirring vessel at 40 to 70 ° C. Subsequently, various NCO group-terminated urethane prepolymers (A) were obtained by introducing the antifoaming agent and proceeding the urethanization reaction for about 2 to 5 hours while keeping the temperature in the stirring vessel at 70 to 90 ° C.

In addition, various polyols (A1), various catalysts (D), and an appropriate amount of antifoaming agent were charged and stirred in a 5 L stirring vessel filled with nitrogen at the mixing ratio shown in Table 1 and Table 2, While maintaining the temperature at 40 to 70 ° C., various OH group terminal curing agents (B) were obtained by mixing and stirring for about 1 to 3 hours.

Next, according to the α values shown in Table 1 and Table 2, the NCO group terminal urethane prepolymer (A) and the catalyst-containing OH group terminal curing agent (B) are mixed with a two-component mixed urethane casting machine. The thermosetting polyurethane elastomer-forming composition of the present invention was prepared, and this composition was poured into a 2 mm-thick flat plate-forming mold preheated to a curing temperature in advance, and the molded product was removed from the mold. The polyurethane elastomer molded product (sheet) of the present invention was obtained by heat-curing in a mold for a minimum time that can be taken out (demolded) and quickly removing the molded product.

The abbreviations of the raw materials used in Table 1 and Table 2 are as follows.
[Isocyanate]
MDI: Millionate MT (manufactured by Nippon Polyurethane Industry Co., Ltd.), 4,4′-MDI, NCO content = 33.5%
TDI; Coronate T-100 (manufactured by Nippon Polyurethane Industry Co., Ltd.), 2,4-TDI, NCO content = 48.2%
[Polyol]
PBA-2500; Nipponporan 3027 (manufactured by Nippon Polyurethane Industry Co., Ltd.), polybutylene adipate, hydroxyl value = 44.9 KOHmg / g
PBA-1000; Nipponran 4009 (manufactured by Nippon Polyurethane Industry Co., Ltd.), polybutylene ethylene adipate, hydroxyl value = 112.0 KOHmg / g
PEA-2000; Nippon Polan 4040 (manufactured by Nippon Polyurethane Industry Co., Ltd.), polyethylene adipate, hydroxyl value = 56.1 KOHmg / g
PTMG-1000; PTMG-1000 (manufactured by Mitsubishi Chemical Corporation), polytetramethylene glycol, hydroxyl value = 112.0 KOHmg / g
1.4-BG; 1,4-butanediol (Mitsubishi Chemical Corporation), hydroxyl value = 1,245 KOHmg / g
TMP: trimethylolpropane (manufactured by Mitsubishi Gas Chemical Company), hydroxyl value = 1,254 KOHmg / g
[Reaction inhibitor]
DDP-2; NIKKOL DDP-2 (manufactured by Nikko Chemicals), di (C12-15) Palace-2 phosphoric acid (10) DDP-4; NIKKOL DDP-4 (manufactured by Nikko Chemicals), di (C12-15) Palace-4 phosphoric acid (11) DDP-10; NIKKOL DDP-10 (manufactured by Nikko Chemicals), di (C12-15) Palace-10
Phosphoric acid (12) PS-236; Phospholan PS-236 (manufactured by Akzo Nobel), mono-di (C10-12) palace-5 phosphoric acid (13) A212C; Prisurf A212C (manufactured by Daiichi Kogyo Seiyaku) Polyoxyethylene tridecyl ether phosphate (14) PEGNPP; dipolyethylene glycol-4-nonylphenyl phosphate (manufactured by Tokyo Chemical Industry Co., Ltd.)
(15) TDP-6; NIKKOL TDP-6 (manufactured by Nikko Chemicals), tri (C12-15) palace-6 phosphate (16) mono-dimethyl phosphate; methyl phosphate (manufactured by Tokyo Chemical Industry Co., Ltd.)
(17) Dibutyl phosphate; dibutyl phosphate (manufactured by Tokyo Chemical Industry Co., Ltd.)
(18) JP-512; (Johoku Chemical Co., Ltd.), alkyl (C12, C14, C16, C18) acid phosphate (19) JP-524; (Johoku Chemical Co., Ltd.), tetracosyl acid phosphate
[catalyst]
(20) POLYCAT-46; (Air Products), mixture of potassium acetate and ethylene glycol (21) DABCO TMR; (Air Products), mixture of quaternary ammonium salt catalyst and ethylene glycol (22) TOYOCAT RX- 5; (manufactured by Tosoh Corporation), trimethylaminoethylethanolamine (23) TOYOCAT TEDA-L33E; (manufactured by Tosoh Corporation), a mixture of triethylenediamine and ethylene glycol
[Other additives]
(24) I-1010; Irganox 1010; (manufactured by BASF Japan) pentaerythritol tetrakis [3- (3 ′, 5′-di-t-butyl-4′-hydroxyphenyl) propionate] antioxidant (25) BYK-052; (BIC Chemie Japan) Non-silicone antifoaming agent

The characteristic evaluation method of the obtained molded sheet is as follows.
(1) JIS-A hardness; measured using an A-type hardness meter in accordance with JIS K7312.
(2) Tensile strength, elongation rate: Measured according to JIS K7312.
(3) Number of cut surface foreign objects: Immediately after removing the molded sheet, the sheet is cut into a strip having a width of about 50 mm, a cut of about 1 mm is made at the end of the center, and the side is pulled and broken, and the broken surface is cut. Considered a face. Five cut surfaces with a width of 20 mm and a thickness of 2 mm were prepared, and each cut surface was observed using a microscope with a magnification of 40 times, the number of irregularities was counted, and the total number of irregularities on the five sheets. Was the number of foreign objects on the cut surface.

The implementation results of the present invention are shown in Examples 1-7. Under any condition, to obtain a thermosetting polyurethane elastomer with high mechanical strength and toughness without damaging the properties of the isocyanate group-terminated urethane prepolymer, with a short molding cycle and without generation of unreacted foreign matter in the molded product. I was able to.

Comparative Example 1 is an example in which the reaction inhibitor (C) was not used, and the resulting NCO group-terminated urethane prepolymer (A) had very high viscosity and color number. Although the number of unreacted foreign substances in the molded product obtained using this NCO group-terminated urethane prepolymer (A) is small, in the casting operation, since the liquid viscosity is high and the flowability is poor, it is sufficiently injected into the mold. It was difficult. Further, the molded product was unsuitable due to coloring.

Comparative Example 2 is an example where the reaction inhibitor (C) of the present invention was excessively blended, and the resulting NCO group-terminated urethane prepolymer (A) had a high color number. Molded products obtained using this NCO group-terminated urethane prepolymer (A) have a long molding time, and the obtained molded products have a large number of unreacted foreign matters and are not suitable.

Comparative Examples 3 to 6 are examples in the case of using the reaction inhibitor (C) other than the present invention, and the obtained molded product has a very large number of unreacted foreign matters, and these foreign matters are the starting points, and the tensile strength is high. Low and unsuitable.

Claims (4)

In the thermosetting polyurethane elastomer-forming composition for industrial machine part members comprising at least an isocyanate group-terminated urethane prepolymer (A) and a hydroxyl group-terminated curing agent (B), the isocyanate group-terminated urethane prepolymer (A) is a reaction inhibitor. (C) A thermosetting polyurethane elastomer-forming composition for industrial machine component members, comprising 5 to 600 ppm of a phosphate ester compound having at least one ethylene oxide in a substituent skeleton as (C). The thermosetting polyurethane elastomer-forming composition for industrial machine component parts according to claim 1, wherein the hydroxyl-terminated curing agent (B) is at least a polyurethane nurating catalyst (D1) and / or as a catalyst (D). A thermosetting polyurethane elastomer-forming composition for industrial machine component parts, comprising an allophanatization catalyst for polyurethane (D2). 3. The thermosetting polyurethane elastomer-forming composition for industrial machine component parts according to claim 1, wherein the mixing ratio of the isocyanate group-terminated urethane prepolymer (A) and the hydroxyl group-terminated curing agent (B) ( A functional group ratio) is a hydroxyl group / isocyanate group = 0.2 to 0.8 (molar ratio). A thermosetting polyurethane elastomer-forming composition for industrial machine part members. The JIS-A hardness of the industrial machine part member obtained by heat-curing the thermosetting polyurethane elastomer-forming composition for industrial machine part member according to any one of claims 1 to 3 is in the range of 60 to 95. Industrial machinery parts characterized by