JP2012246335A - Two-component polyurethane elastomer composition and molded article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-component polyurethane elastomer composition excellent in water resistance, wear resistance and mechanical strength, and a molded article using the same.SOLUTION: The polyurethane elastomer composition comprises a base resin containing an isocyanate group-terminated urethane prepolymer (A), and a curing agent containing an isocyanate group-reactive compound (B). The prepolymer (A) is obtained from a polyisocyanate (a1) and a polyol (a2), tolylene diisocyanate is contained as the polyisocyanate (a1), and a polyester polyol (a2-1) using 50-100 mol% of sebacic acid in a dibasic acid component constituting the polyol (a2) is contained. The reactive compound (B) is 3,3'-dichloro-4,4'-diaminodiphenylmethane.

Description

  The present invention relates to a two-component polyurethane elastomer composition excellent in wear resistance and water resistance, and a molded article. More specifically, the present invention relates to a two-component polyurethane elastomer composition that achieves both excellent wear resistance and water resistance required under severe conditions, and molded articles such as industrial parts and machine parts using the same. .

  Conventionally, the two-component polyurethane elastomer composition has good performance such as tensile properties and abrasion resistance, and therefore, for example, industrial members such as rollers, casters, belts, polishing pads, and parts for industrial machines. It has been used for a wide range of applications as a molded article.

  However, with the rapid automation in recent years, the production speed is increasing at an accelerating rate, and the production conditions and the use conditions of the molded product when molding with the polyurethane elastomer composition tend to be more severe. For this reason, the conventional composition has insufficient performance such as wear resistance, water resistance, and mechanical strength, and is feared to be difficult to be applied to various uses as described above.

  Various proposals have been made so far to deal with such problems.

  For example, as means for imparting solvent resistance and water resistance to a polyurethane elastomer, succinic acid and / or adipic acid is used as the carboxylic acid component, and mono- or polyoxyalkylene glycol having a number average molecular weight of 400 or less is used as the glycol component. In the polyester polyol obtained by dehydrating and condensing these together with castor oil, it is known to use a polyester polyol in which the amount of castor oil used is 10 to 60% by weight based on the polyester polyol obtained (for example, patents) Reference 1).

  However, although the polyurethane elastomer using the polyester polyol described in Patent Document 1 has relatively good water resistance, it has a problem that it is still unsuitable for practical use because of insufficient wear resistance.

  Further, in the polyurethane elastomer composed of succinic polyester polyol and polyisocyanate, the succinic polyester polyol uses succinic acid as a main component of the carboxylic acid component, and further aromatic carboxylic acid is 3 to 50 mol% in the total carboxylic acid component. A polyurethane elastomer that is obtained by use is known (for example, see Patent Document 2).

  However, the polyurethane elastomer described in Patent Document 2 has a relatively good water resistance as in Patent Document 1, but has a problem that it is not suitable for practical use because sufficient abrasion resistance cannot be obtained. .

  Further, in a two-pack type composition for glass polishing polyurethane pad comprising a main agent containing an isocyanate group-terminated urethane prepolymer, an isocyanate group reactive compound, water as a foaming agent, an inorganic abrasive and a curing agent containing a catalyst. When the isocyanate group-terminated urethane prepolymer is a mixture of at least tolylene diisocyanate, poly (tetramethylene ether) glycol and polycaprolactone triol, and poly (tetramethylene ether) glycol and polycaprolactone triol, the average number of functional groups is 2. It is an isocyanate group-terminated urethane prepolymer obtained by reacting each of them so as to be within the range of 1 to 2.7, and the isocyanate group-reactive compound is at least 4,4′-diamino-3 , '- and dichloro methane, two-liquid composition for glass polishing polyurethane pad made of poly (tetramethylene ether) glycol is known (e.g., see Patent Document 3).

  However, when polishing a glass product as a workpiece using the polishing pad made of the two-component composition described in Patent Document 3, severe frictional heat generated between the polishing pad and the workpiece is obtained. The pressure causes a harmful effect called “sagging”, and the hardness (elastic modulus) changes during the polishing operation, making it difficult to use it for precise polishing in a short time.

  Further, in the two-component composition of Patent Document 3, poly (tetramethylene ether) glycol is essentially used as a main agent and a curing agent, so that the water resistance is relatively good, but also the point of wear resistance. There was a problem of being inferior.

  As described above, regarding a polyurethane elastomer composition using a polyester polyol, a two-component polyurethane elastomer composition having excellent performances in terms of water resistance, abrasion resistance, and mechanical strength, and a molded product using the same. Although there is a strong demand for development, it has not yet been found.

JP 2010-126659 A JP 2009-298934 A JP-A-2005-068168

  An object of the present invention is to provide a two-component polyurethane elastomer composition excellent in water resistance, abrasion resistance, and mechanical strength, and a molded article using the same.

  As a result of intensive studies to solve the above problems, the present inventors combined a main agent containing an isocyanate group-terminated urethane prepolymer having a specific composition and a curing agent containing an isocyanate group-reactive compound. It has been found that a two-component polyurethane elastomer composition having excellent performance in terms of water resistance, abrasion resistance, and mechanical strength, and a molded product can be obtained, and the present invention has been completed. .

  That is, the present invention is a polyurethane elastomer composition comprising a main agent containing an isocyanate group-terminated urethane prepolymer (A) and a curing agent containing an isocyanate group-reactive compound (B), the prepolymer (A) Is obtained from the polyisocyanate (a1) and the polyol (a2), contains tolylene diisocyanate as the polyisocyanate (a1), and sebacic acid in the dibasic acid component constituting the polyol (a2) is 50 to 100 A two-component type containing a polyester polyol (a2-1) used in mol% and wherein the isocyanate group-reactive compound (B) is 3,3′-dichloro-4,4′-diaminodiphenylmethane The present invention relates to a polyurethane elastomer composition.

  The present invention also relates to a molded article obtained by using the two-component polyurethane elastomer composition.

  Since the two-component polyurethane elastomer composition of the present invention can exhibit excellent performance in terms of water resistance, abrasion resistance, and mechanical strength, for example, roller, cam, gear, gear, connector, caster, belt, polishing It can be used for various molded products such as pads, chassis, bearings, magnetic tape guides, pump units, medical equipment valves, slide parts, industrial parts, industrial machine parts, slide parts, automobile parts, electrical / electronic parts, etc. is there.

  The two-component polyurethane elastomer composition of the present invention can be obtained by mixing a predetermined amount of an isocyanate group-terminated urethane prepolymer (A) as a main agent and an isocyanate group reactive compound (B) as a curing agent when used. it can.

  The isocyanate group-terminated urethane prepolymer (A) [hereinafter referred to as prepolymer (A). ] Can be obtained by a known synthesis method using polyisocyanate (a1) and polyol (a2), and the synthesis method is not particularly limited.

  The two-component polyurethane elastomer composition of the present invention essentially contains tolylene diisocyanate (TDI) as the polyisocyanate (a1). By containing the TDI, the reaction rate at the time of curing of the two-component polyurethane elastomer composition obtained can be easily controlled, and excellent workability and moldability can be obtained.

  However, when a polyisocyanate other than TDI, such as 4,4′-diphenylmethane diisocyanate (MDI), is used alone as the polyisocyanate (a1) as in the prior art, however, The reaction rate is too high, and the control cannot be performed well, resulting in problems that workability and formability become extremely difficult.

  In the TDI, 2,4-tolylene diisocyanate (referred to as 2,4-isomer) and 2,6-tolylene diisocyanate (referred to as 2,6-isomer) can be used as isomers. However, in general, the 2,4-isomer alone and a mixture of the 2,4-isomer and the 2,6-isomer (for example, a mixture of 2,4-isomer / 2,6-isomer = 80/20 mass ratio, etc.) Are commercially available, and any of them can be used in the present invention.

  In the present invention, together with the TDI, a polyisocyanate (a1 ′) other than TDI can be used as long as the object of the present invention is not impaired. In this case, the amount of (a1 ′) used is preferably less than 50 mol% with respect to the total number of moles of polyisocyanate [ie (a1) + (a1 ′)].

  The polyisocyanate (a1 ′) other than the TDI may be aromatic, alicyclic or aliphatic, such as tolidine diisocyanate (TODI), diphenylmethane diisocyanate (MDI; its 4,4′-form). 2,4′-isomer, or 2,2′-isomer, or a mixture thereof), polymethylene polyphenyl polyisocyanate, carbodiimidized diphenylmethane polyisocyanate, xylylene diisocyanate (XDI), 1,5-naphthalene diisocyanate (NDI) ), Aromatic diisocyanates such as tetramethylxylene diisocyanate, 3,3′-dimethyl-4,4′-biphenyl diisocyanate, or isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate (hydrogenated MDI), hydrogenated key Alicyclic diisocyanates such as Li diisocyanate (hydrogenated XDI) or hexamethylene diisocyanate, dimer acid diisocyanate, aliphatic diisocyanates such as norbornene diisocyanate. Moreover, the polyisocyanate currently used for manufacture of normal polyurethane elastomers, such as the carbodiimide modified body, allophanate modified body, dimer, trimer of these diisocyanate, is mentioned. These may be used alone or in combination of two or more.

  Next, the polyol (a2) used in the present invention will be described.

  The polyol (a2) used in the present invention is a polyester polyol (Sebasic acid is used in the range of 50 to 100 mol%, preferably 80 to 100 mol%, in the dibasic acid component constituting the polyol (a2). a2-1), and preferably has an acid value of 0.0 to 1.0 and a hydroxyl value of 37 to 187, more preferably an acid value of 0.0 to 0.00. 5. The hydroxyl value is in the range of 56-112. The unit of acid value and hydroxyl group is usually “mgKOH / g”, but is omitted in the present invention.

  Moreover, the said polyester polyol (a2-1) is obtained by making a glycol component and a dibasic acid component react by a well-known method, Sebacic acid is 50-100 mol% in the said dibasic acid component, Preferably it is 80. ~ 100 mol% used.

  The number average molecular weight (hereinafter referred to as Mn) of the polyester polyol (a2-1) is preferably in the range of 600 to 3000, more preferably 1000 to 2000. If the Mn of (a2-1) is within such a range, a polyurethane elastomer having excellent elasticity can be obtained, and the hardness can be easily adjusted, which is preferable. When Mn is smaller than 600, the resulting polyurethane elastomer tends to be inferior in elasticity, and when Mn is larger than 3000, high hardness tends to be relatively difficult to adjust.

  In addition, Mn described in the present invention is a value in terms of polystyrene measured by gel permeation chromatography (GPC).

  The glycol component is preferably an aliphatic short-chain diol having 2 to 18 carbon atoms, such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, , 3-butanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-hexanediol 2,2,4-trimethyl 1,3-pentanediol, 2-ethyl 1,3-hexanediol, 2-methyl 1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, , 12-octadecanediol and the like, and these can be used alone or in combination of two or more.

  The dibasic acid component is one containing 50 to 100 mol%, preferably 80 to 100 mol%, more preferably 100 mol% of sebacic acid.

  In this case, the dibasic acid that can be used in combination with sebacic acid at less than 50 mol% is preferably an aliphatic dibasic acid. For example, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, 1, Single or two or more of 10-decanedicarboxylic acid, 1,12-dodecanedicarboxylic acid and the like can be used. In addition, an aromatic dibasic acid and an alicyclic dibasic acid may be used in combination as long as the effects of the present invention are not impaired. For example, phthalic acid, isophthalic acid, terephthalic acid, hexahydroterephthalic acid, hexahydroisophthalic acid Or those anhydrides, lower esters and the like can be used alone or in combination of two or more.

  The production method of the polyester polyol (a2-1) is not particularly limited. For example, an esterification catalyst usually used for the dibasic acid component containing sebacic acid within the above range and the glycol component is used. A method of producing by reacting in the presence or without a catalyst is preferred. The reaction at that time may be carried out under any conditions of normal pressure, pressurization, and reduced pressure.

  If the polyester polyol (a2-1) is contained in the polyol (a2), preferably 80 to 100 mol%, more preferably 90 to 100 mol%, excellent wear resistance, water resistance, and durability can be obtained. Obtainable.

In the present invention, sebacic acid having high crystallinity is used as a main component of the polyester polyol (a2-1), so that the phase separation between the soft and hard segments of the polyurethane molecular chain proceeds to an appropriate state, thereby It was speculated that the wear resistance was remarkably improved. In addition, since sebacic acid is rich in hydrophobicity, by using sebacic acid in a specific range amount,
The hydrophobicity of the polyurethane elastomer can be remarkably improved and the water resistance can be remarkably improved.
Such excellent wear resistance and water resistance improvement effect is an effect that is never expressed when an aliphatic dibasic acid other than sebacic acid such as succinic acid or adipic acid is used. By using it, it is an excellent effect found for the first time in the present invention.

  Examples of the other polyol (a2 ′) that can be used in combination with the polyester polyol (a2-1) include a normal polyester polyol composed of a dibasic acid component such as adipic acid and the short-chain diol component. Polyester polyols obtained by ring-opening polymerization of lactones using a short-chain glycol as a reaction initiator, polyether polyols such as polytetramethylene glycol and polypropylene glycol, and the like. Of course, these polyols used in combination may have an average functional group number exceeding 2.0, and can be used within a range not impairing the effects of the present invention.

  As a means for obtaining the isocyanate group-terminated urethane prepolymer (A) from the polyol (a2) containing the polyester polyol (a2-1) and the polyisocyanate (a1), conventional known production methods can be used.

  Equivalent ratio of the isocyanate group (NCO group) of the polyisocyanate (a1) and the hydroxyl group (OH group) of the polyol (a2) containing the polyester polyol (a2-1) used at that time [ie, NCO / OH equivalent ratio] Is preferably in the range of 1.5 to 2.2, more preferably in the range of 1.7 to 2.0. When the NCO / OH equivalent ratio is in such a range, the workability, moldability, and physical properties (for example, mechanical strength) of the obtained two-component polyurethane elastomer composition are excellent. When the NCO / OH equivalent ratio is less than 1.5, the viscosity of the prepolymer (A) is excessively increased and workability tends to be lowered, which is not preferable. On the other hand, if the NCO / OH equivalent ratio exceeds 2.2, the resulting polyurethane elastomer tends to lose its elasticity, which is not preferable.

  In the present invention, if necessary, before, during, and after the synthesis of the prepolymer, for example, a reactivity modifier, an antioxidant, an ultraviolet absorber, a flame retardant, a stabilizer, a colorant, a filler, etc. Various additives may be added.

  Next, isocyanate group-reactive compound (B) [hereinafter referred to as reactive compound (B). ] The hardening | curing agent containing is demonstrated.

  In the present invention, 3,3'-dichloro-4,4'-diaminodiphenylmethane (MBOCA), which is the reactive compound (B), is used as a curing agent. By using MBOCA as an essential component, a molded article having excellent wear resistance can be obtained.

  The equivalent ratio of the NCO group of the prepolymer (A) as the main agent to the active hydrogen [NH] in the curing agent containing the reactive compound (B) is preferably NH / NCO = 0.8 to 1. A range of zero. When the NH / NCO equivalent ratio is within such a range, a polyurethane elastomer molded product having excellent performance such as water resistance, abrasion resistance, durability, and mechanical strength can be obtained.

  In this invention, the prepolymer (A) obtained from the polyisocyanate (a1) containing the said TDI and the polyol (a2) containing the polyester polyol (a2-1) which uses sebacic acid in a dibasic acid component is contained. In order to produce a two-component polyurethane elastomer composition comprising the main agent and MBOCA which is a curing agent containing the reactive compound (B), a conventionally known production method can be used.

  Moreover, water, a catalyst, a foam stabilizer, etc. can also be included in a hardening | curing agent as needed. The quantity of a hardening | curing agent can be adjusted by mix | blending and mixing water, a catalyst, etc. as a containing component with the said reactive compound (B). The water used is preferably pure water or ion exchange water. The catalyst may be any known organometallic compound, polyol compound, amine compound, etc. as long as it promotes foaming and curing, and is preferably an amine compound, for example, a tertiary amine such as triethylamine or triethylenediamine. Specific examples thereof include nitrogen compounds such as morpholine and N-methylmorpholine, metal salts such as potassium acetate and zinc stearate, and organometallic compounds such as dibutyltin dilaurate and dibutyltin oxide. Furthermore, the foam stabilizer is preferably a silicone-based surfactant, and known ones such as SH-193 (trademark, manufactured by Toray Dow Corning Silicone), SF-2962 (manufactured by the same company) and the like can be used.

  An auxiliary agent may be added to the curing agent containing the reactive compound (B), if necessary, in addition to water, a foam stabilizer, a catalyst, and the like. Examples of such auxiliaries include additives such as antioxidants, ultraviolet absorbers, and flame retardants. These auxiliaries can be known and are not particularly limited.

  The polyurethane elastomer composition of the present invention can be obtained by blending the main agent and the curing agent prepared as described above and immediately mixing them sufficiently.

  About the operation method which mixes the hardening | curing agent containing the said reactive compound (B), and the main ingredient containing the said prepolymer (A), inject | pours in a shaping | molding die, what is necessary is just to employ | adopt a well-known technique, There is no particular limitation.

  If an example of the manufacturing method of the molded article using the two-pack type polyurethane elastomer composition of this invention is shown, the main ingredient containing the said prepolymer (A) and the hardening | curing agent containing the reactive compound (B) will be respectively shown. Preferably, the molded article of the present invention is obtained by heating and mixing at 70 to 120 ° C., and then pouring, curing, and aging in a molding die preferably heated to 90 to 110 ° C. Can do.

  In order to obtain a foam (that is, a foamed polyurethane elastomer) using the two-component polyurethane elastomer composition of the present invention, water, a catalyst, a foam stabilizer and the like are added to the curing agent to form, foam, and cure. Just do it.

The density of the foamed polyurethane elastomer varies depending on the use, but is usually preferably 0.3 to 0.7 g / cm ³ . The “foamed polyurethane elastomer” as used in the present invention is meant to include those in which closed cells and open cells are formed in the foamed polyurethane elastomer.

  Examples of the two-component polyurethane elastomer composition of the present invention include foam stabilizers, antioxidants, defoamers, ultraviolet absorbers, abrasive grains, fillers, pigments, thickeners, surfactants, flame retardants, Known additives such as plasticizers, lubricants, antistatic agents, heat stabilizers, blending resins and the like can be used at any stage of the production process as long as they do not impair the object of the present invention. The additive described in the present invention is an example, and the kind thereof is not particularly limited.

  Since the two-component polyurethane elastomer composition of the present invention can exhibit excellent performance such as water resistance, abrasion resistance, and mechanical strength, for example, roller, cam, gear, gear, connector, caster, belt, polishing It can be used for various molded products such as pads, chassis, bearings, magnetic tape guides, pump units, medical equipment valves, slide parts, industrial parts, industrial machine parts, slide parts, automobile parts, electrical / electronic parts, etc. is there.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the scope of the present invention is not limited only to these examples.
Further, in the present invention, unless otherwise specified, “part” is “part by mass” and “%” is “mass%”.
The measurement method and evaluation method used in the present invention are as follows.

[Method for measuring isocyanate group equivalent (NCO equivalent) of prepolymer (A)]
The NCO equivalent of the prepolymer (A) is measured in accordance with JIS K 7301 by dissolving a sample in dry toluene, adding an excess of di (n-butyl) amine solution and reacting it, and then remaining di (n- (Butyl) amine was determined by back titration with a hydrochloric acid standard solution.

[Measurement method of number average molecular weight]
The number average molecular weight (Mn) is a value calculated by the following formula based on the acid value and the hydroxyl value measured by the titration method.
Number average molecular weight = 56100 × 2 / (acid value + hydroxyl value)

[Create evaluation sheet]
A predetermined amount of prepolymer (A) heated to 80 ° C. and a predetermined amount of reactive compound (B) heated to 120 ° C. were sufficiently stirred and mixed for 1 minute.
Next, 150 g of the obtained mixture was poured into a glass mold (300 mm × 300 mm) having a spacer of 2 mm heated to 110 ° C., and immediately left in a glass mold of 110 ° C. for 2 hours. 14 hours) and an evaluation sheet was obtained.

[Measurement method of hardness (JIS A)]
The hardness (JIS A) of the evaluation sheet was measured with a type A durometer specified in JIS K 7215 (plastic durometer hardness test method).

[Measurement method of tensile properties]
In accordance with JIS K 7311, the tensile properties of the evaluation sheet were measured.

[Measurement methods and evaluation criteria for wear resistance]
In accordance with JIS K 7312-1996 (Taber abrasion test), the weight loss (mg) of the molded article using the urethane elastomer is 1 kg at a load of 1000 kg using a Taber abrasion tester (Toyo Seiki Seisakusho, rotary ablation tester). It was measured. The evaluation criteria for wear resistance are as follows.
○: When wear loss is 110 mg or less, wear resistance is excellent.
X: When abrasion loss exceeds 110 mg, it is inferior to abrasion resistance.

[Measurement method and evaluation criteria for water resistance]
The evaluation sheet prepared by the above method was immersed in hot water at 80 ° C. for 1 week, and the tensile strength retention rate of the evaluation sheet after the water resistance test was measured in accordance with JIS K 7311. The evaluation criteria for water resistance are as follows.
◯: Excellent water resistance when the tensile force retention is 50% or more.
X: When the tensile force retention is less than 50%, the water resistance is poor.

[Synthesis Example 1]
<< Synthesis of Polyester Polyol (a2-1-1) >>
In a 5-liter four-necked flask, 226.6 parts of ethylene glycol (hereinafter referred to as EG), 119.1 parts of 1,2-propylene glycol (hereinafter referred to as 1,2PG), 812.1 parts of sebacic acid (hereinafter referred to as SebA), and tetraisopropyl Titanate (hereinafter referred to as TiPT) (0.029 parts) was charged, and the reaction was conducted at an internal temperature of 220 ° C. under a nitrogen stream from a nitrogen introduction tube.
After the reaction for 18 hours, a polyester polyol (a2-1-1) as a white solid at room temperature having an acid value of 0.24, a hydroxyl value of 110.6, and a number average molecular weight (Mn) of 1012 was obtained.

[Synthesis Example 2]
<< Synthesis of Polyester Polyol (a2-1-2) >>
In a 5-liter four-necked flask, 251.5 parts of EG, 132.1 parts of 1,2PG, 461.8 parts of SebA, 333.7 parts of adipic acid (hereinafter AA), and 0.030 parts of TiPT are charged. The reaction was carried out at an internal temperature of 220 ° C. under a nitrogen stream from a nitrogen introduction tube.
After the reaction for 18 hours, an ordinary white solid polyester polyol (a2-1-2) having an acid value of 0.30, a hydroxyl value of 112.0, and Mn999 was obtained.

[Synthesis Example 3]
<< Synthesis of Polyester Polyol (a2-1-3) >>
A 5-liter four-necked flask was charged with 282.2 parts of EG, 148.2 parts of 1,2PG, 773.6 parts of AA, and 0.030 parts of TiPT. The reaction was performed at 220 ° C.
After the reaction for 18 hours, an ordinary white solid polyester polyol (a2-1-3) having an acid value of 0.35, a hydroxyl value of 113.6, and Mn985 was obtained.

[Synthesis Example 4]
<< Synthesis of Polyester Polyol (a2-1-4) >>
A 5-liter 4-neck flask is charged with 257.4 parts of EG, 135.2 parts of 1,2PG, 379.8 parts of SeBA, 411.7 parts of AA, and 0.030 parts of TiPT, and a nitrogen introduction tube The reaction was further carried out at an internal temperature of 220 ° C. under a nitrogen stream.
After the reaction for 18 hours, a normal temperature white solid polyester polyol (a2-1-4) having an acid value of 0.20, a hydroxyl value of 112.0, and Mn1000 was obtained.

[Synthesis Example 5]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-1) ≫
In a 2-liter 4-neck flask, 1000.0 parts of the polyester polyol (a2-1-1) obtained in Synthesis Example 1 and TDI-80 (trademark: Cosmonate T-80, Mitsui Chemicals) as the polyisocyanate (a1) 326.9 parts by weight (mixture of 2,4-tolylene diisocyanate / 2,6-tolylene diisocyanate = 80/20 mass ratio) manufactured by Co., Ltd. (set to NCO / OH = 1.90 equivalent ratio), nitrogen introduced The reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from the tube to obtain a prepolymer (A-1) having an NCO group equivalent of 761.

[Synthesis Example 6]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-2) ≫
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-1) obtained in Synthesis Example 1 and 309.7 parts of TDI-80 as polyisocyanate (a1) were charged (NCO / OH = The reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen inlet tube to obtain a prepolymer (A-2) having an NCO group equivalent of 841.

[Synthesis Example 7]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-3) ≫
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-2) obtained in Synthesis Example 2 and 313.8 parts of TDI-80 as polyisocyanate (a1) were charged (NCO / OH = 1. A ratio of 80 equivalents was set), and the reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen inlet tube to obtain a prepolymer (A-3) having an NCO group equivalent of 821.

[Synthesis Example 8]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-4) ≫
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-3) obtained in Synthesis Example 3 and 336.1 parts of TDI-80 as polyisocyanate (a1) were charged (NCO / OH = 1.90 equivalent ratio), the reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen inlet tube to obtain a prepolymer (A-4) having an NCO group equivalent of 724.

[Synthesis Example 9]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-5) ≫
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-3) obtained in Synthesis Example 3 and 318.4 parts of TDI-80 as polyisocyanate (a1) were charged (NCO / OH = 1. A ratio of 80 equivalents was set), and the reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen inlet tube to obtain a prepolymer (A-5) having an NCO group equivalent of 841.

[Synthesis Example 10]
≪Synthesis of isocyanate group-terminated urethane prepolymer (A-6) ≫
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-4) obtained in Synthesis Example 4 and 313.5 parts of TDI-80 as polyisocyanate (a1) were charged (NCO / OH = 1. A ratio of 80 equivalents was set), and the reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen introduction tube to obtain a prepolymer (A-6) having an NCO group equivalent of 822.

[Synthesis Example 11]
<< Synthesis of isocyanate group-terminated urethane prepolymer (A-7) >>
In a 2-liter four-necked flask, 1000.0 parts of the polyester polyol (a2-1-1) obtained in Synthesis Example 1 and 444.5 parts of MDI as polyisocyanate (a1) were charged (NCO / OH = 1. The reaction was carried out for 12 hours at an internal temperature of 80 ° C. under a nitrogen stream from a nitrogen inlet tube to obtain a prepolymer (A-7) having an NCO group equivalent of 915.

[Example 1]
100.0 parts of prepolymer (A-1) obtained in Synthesis Example 5 and 15.8 parts of 3,3′-dichloro-4,4′-diaminodiphenylmethane (MBOCA) as a reactive compound (B) Then, the mixture was sufficiently stirred and mixed to obtain the two-component polyurethane elastomer composition (X-1) of the present invention.
Next, 150 g of the composition (X-1) was poured into a glass mold (300 mm × 300 mm) having a spacer of 2 mm heated to 110 ° C., and immediately left in a glass mold of 110 ° C. for 2 hours. Cure (110 ° C., 14 hours) was performed to prepare a molded article (P-1) of the present invention.
The molded product (P-1) of the present invention was a sheet having a thickness of 2 mm and good surface flatness, and had excellent performance as shown in Table 1.

[Example 2]
100.0 parts of the prepolymer (A-2) obtained in Synthesis Example 6 and 14.3 parts of MBOCA as the reactive compound (B) were mixed and mixed thoroughly, and the two-component polyurethane elastomer of the present invention. A composition (X-2) was obtained.
Next, after-curing was performed using the composition (X-2) under the same operating conditions as in Example 1, to produce a molded article (P-2) of the present invention.
The molded product (P-2) of the present invention was a sheet having a thickness of 2 mm and good surface flatness, and had excellent performance as shown in Table 1.

Example 3
100.0 parts of the prepolymer (A-3) obtained in Synthesis Example 7 and 14.6 parts of MBOCA as the reactive compound (B) were mixed and sufficiently stirred and mixed, and the two-component polyurethane elastomer of the present invention A composition (X-3) was obtained.
Next, after-curing was performed using the composition (X-3) under the same operating conditions as in Example 1, to produce a molded article (P-3) of the present invention.
The molded product (P-3) of the present invention was a sheet having a thickness of 2 mm and good surface flatness, and had excellent performance as shown in Table 1.

[Comparative Example 1]
100.0 parts of the prepolymer (A-4) obtained in Synthesis Example 8 and 16.6 parts of MBOCA as the reactive compound (B) were mixed and sufficiently stirred and mixed, and the polyurethane elastomer composition (X-4 )
Next, using the composition (X-4), after-curing was performed under the same operating conditions as in Example 1, and a molded product (P-4) was produced.
The molded product (P-4) was a sheet having a thickness of 2 mm and good surface flatness, but as shown in Table 2, it was inferior in wear resistance and water resistance.

[Comparative Example 2]
100.0 parts of the prepolymer (A-5) obtained in Synthesis Example 9 and 14.3 parts of MBOCA as the reactive compound (B) were mixed and sufficiently stirred and mixed to obtain a two-component polyurethane elastomer composition ( X-5) was obtained.
Next, after-curing was performed using the composition (X-5) under the same operating conditions as in Example 1, to produce a molded product (P-5).
The molded product (P-5) was a sheet having a thickness of 2 mm and good surface flatness, but as shown in Table 2, it was inferior in wear resistance and water resistance.

[Comparative Example 3]
100.0 parts of the prepolymer (A-6) obtained in Synthesis Example 10 and 14.6 parts of MBOCA as the reactive compound (B) were mixed and sufficiently stirred and mixed to obtain a two-component polyurethane elastomer composition ( X-6) was obtained.
Subsequently, using the composition (X-6), after-curing was performed under the same operating conditions as in Example 1, and a molded article (P-6) was produced.
The molded product (P-6) was a sheet having a thickness of 2 mm and good surface flatness, but as shown in Table 2, it was inferior in wear resistance and water resistance.

[Comparative Example 4]
100.0 parts of the prepolymer (A-7) obtained in Synthesis Example 11 and 13.1 parts of MBOCA as the reactive compound (B) were mixed and sufficiently stirred and mixed to obtain a two-component polyurethane elastomer composition ( X-7) was obtained. However, since the composition (X-7) was cured during stirring and mixing, it could not be poured into a glass mold and a sheet as a molded product could not be obtained.

The abbreviations in the table mean the following compound names.
EG: ethylene glycol 1,2PG: 1,2-propylene glycol SebA: sebacic acid AA: adipic acid

  Since the two-component polyurethane elastomer composition of the present invention can exhibit excellent performance such as water resistance, abrasion resistance, and mechanical strength, for example, roller, cam, gear, gear, connector, caster, belt, polishing It can be used for various molded products such as pads, chassis, bearings, magnetic tape guides, pump units, medical equipment valves, slide parts, industrial parts, industrial machine parts, slide parts, automobile parts, electrical / electronic parts, etc. is there.

Claims (6)

A two-component polyurethane elastomer composition comprising a main agent containing an isocyanate group-terminated urethane prepolymer (A) and a curing agent containing an isocyanate group-reactive compound (B), wherein the prepolymer (A) is a polyisocyanate. It is obtained from (a1) and polyol (a2), contains tolylene diisocyanate as the polyisocyanate (a1), and uses 50 to 100 mol% of sebacic acid in the dibasic acid component constituting the polyol (a2) A two-component polyurethane elastomer composition comprising the polyester polyol (a2-1) to be produced and the isocyanate group-reactive compound (B) being 3,3′-dichloro-4,4′-diaminodiphenylmethane object. The two-component polyurethane elastomer composition according to claim 1, wherein the polyol (a2) is a polyol containing 80 to 100 mol% of the polyester polyol (a2-1). The two-component polyurethane elastomer composition according to claim 1, wherein the dibasic acid component constituting the polyester polyol (a2-1) contains 50 to 100 mol% of sebacic acid. The two-component polyurethane elastomer composition according to claim 1, wherein the number average molecular weight of the polyol (a2) is in the range of 600 to 3,000. In the prepolymer (A), the ratio of the isocyanate group equivalent of the polyisocyanate (a1) and the hydroxyl group equivalent of the polyol (a2) [that is, the NCO / OH equivalent ratio] is in the range of 1.5 to 2.2. The two-component polyurethane elastomer composition according to claim 1. A molded article obtained by using the two-component polyurethane elastomer composition according to any one of claims 1 to 5.