JP2013163778A - Two-pack thermosetting polyurethane elastomer composition, elastic molding, and roll - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a two-pack thermosetting polyurethane elastomer composition which exhibits excellent mechanical strength, compressive strain, rebound resilience, and water resistance.SOLUTION: A two-pack thermosetting polyurethane elastomer composition is obtained by blending a urethane prepolymer (A) having a terminal NCO group and a curing agent (B). The (A) is obtained by indispensably using diphenylmethane diisocyanate as a polyisocyanate (a1) and a polycarbonate diol as a polyol (a2), and the (B) indispensably includes a diol (b1) with a molecular weight of 50 to 150, a polyether polyol (b2) with Mn of ≥600 and <2,000, and a propylene oxide adduct (b3) of glycerin with Mn of 200 to 400, wherein each of the (b1) to the (b3) has no aromatic ring, and 20 to 60 pts.mass of (b1) and 1 to 20 pts.mass of (b3) are included therein with respect to 100 pts.mass. of the (b2).

Description

  The present invention relates to a two-component thermosetting polyurethane elastomer composition, an elastic molded body using the same, and a roll. More specifically, it has excellent mechanical strength (tensile strength, elongation), water resistance, and moderately reduced compressive strain and impact resilience. For example, rolls, tires, belts, hoses, pipes, tubes, nets, cushions, industrial use The present invention relates to a two-component thermosetting polyurethane elastomer composition for forming a urethane elastomer suitable for an elastic molded body used in a wide range of applications such as parts, clothing materials, hygiene materials, and sports goods, and an elastic molded body using the same.

  For example, in rolls, tires, belts, and other elastic molded products used in various fields such as the paper industry and printing industry, mechanical strength (tensile strength, elongation), water resistance, compression resistance, low resilience Performance such as elasticity is essential. Therefore, conventionally, in order to obtain such performance, an elastomer composition using, for example, a thermosetting polyurethane elastomer, nitrile butadiene rubber (NBR) or the like has been used.

  However, it is difficult to withstand severe use conditions such as high-speed printing, continuous production, maintenance-free, etc., which have been remarkably advanced in recent years, with elastic molded bodies using such conventional resin compositions. It was a problem.

  On the other hand, in a two-component thermosetting polyurethane elastomer composition, 3,3′-dichloro-4,4′- has been conventionally used as an aromatic amine curing agent in many applications such as waterproofing materials, flooring materials, and paving materials. Diaminodiphenylmethane (MBOCA) has been formulated.

  However, the elastic molded product obtained using MBOCA has practical problems such as poor water resistance and mechanical strength (particularly tensile strength and elongation).

  In addition, MBOCA is concerned about adverse effects on organisms and nature such as indegradability, toxicity, genotoxicity, and carcinogenicity, and its substitution has been demanded.

In order to improve such a problem, various proposals have been made so far.
In a polyurethane elastomer composition comprising an NCO group-terminated prepolymer and a mixture of a long-chain polyol, a short-chain diol and a short-chain triol, diphenylmethane diisocyanate polyisocyanate and hexamethylene diisocyanate polyisocyanate are used as polyisocyanates of the NCO group-terminated prepolymer. Diisocyanate diisocyanate based diisocyanate and diphenylmethane diisocyanate based diisocyanate and / or diphenylmethane diisocyanate containing diphenylmethane diisocyanate dimer compound and / or carbodiide-modified diphenylmethane diisocyanate and hexamethylene diisocyanate based polyisocyanate Hexamethylene di Isocyanurate ring-containing modified form of socyanate, or uretdione ring and isocyanurate ring-containing modified form of hexamethylene diisocyanate, the polyol for the NCO group-terminated prepolymer, and the long-chain polyol as polycarbonate polyol and polycaprolactone polyol A polyurethane elastomer composition for two-liquid casting which is a combined use and / or a poly (carbonate / caprolactone) polyol is known (for example, see Patent Document 1).

  The polyurethane elastomer composition for two-liquid casting of Patent Document 1 is said to have good workability (defoaming property by reducing viscosity, shortening of demolding time, etc.) and physical strength.

  However, since Patent Document 1 uses an aromatic active hydrogen compound such as 1,4-bis (2-hydroxyethoxy) benzene as a short-chain diol, it has high crystallinity, so that the resulting curing agent is stable. There was a problem of poor workability and poor workability.

  Further, a polyisocyanate, at least one chain extender selected from the group consisting of a specific diol, bis (hydroxyethyl) terephthalate, and 1,4-bis (hydroxyethyl) cyclohexane, and a macro having a weight average molecular weight of 500 to 6000. A thermoplastic resin composition containing 30% by weight or more of a thermoplastic polyurethane elastomer obtained from an active hydrogen compound containing a polyol (however, different from the chain extender) is known (for example, see Patent Document 2). .)

  Patent Document 2 can obtain a thermoplastic resin composition having good compression set characteristics and good adhesion between resins, and a molded product obtained from the thermoplastic resin composition is easy to recycle and provides various protections. It can be used for comfortably used seats, furniture, etc. used in nets, aircraft, ships and vehicles.

  However, since Patent Document 2 also uses an aromatic active hydrogen compound such as 1,4-bis (2-hydroxyethoxy) benzene, it has high crystallinity, and thus the resulting curing agent has poor stability. There was a problem that workability was inferior.

  As described above, the prior art is still insufficient, and a two-component thermosetting polyurethane that can exhibit excellent performance such as mechanical strength (tensile strength, elongation), low compression strain, low resilience, and water resistance in a well-balanced manner. Development of an elastomer composition, a method for producing an elastic molded body using the same, and an elastic molded body has been desired.

Japanese Patent Laid-Open No. 10-60071 JP 2006-328221 A

  Problems to be solved by the present invention include a two-component thermosetting polyurethane elastomer composition excellent in performance such as mechanical strength (tensile strength, elongation), compression strain, impact resilience, water resistance, and the like, a method for producing an elastic molded product, and It is to provide an elastic molded body.

  As a result of intensive studies to solve the above problems, the present inventor has found that in a two-component thermosetting polyurethane elastomer composition in which a urethane prepolymer having an isocyanate group at its end and a curing agent are blended, Diphenylmethane diisocyanate as isocyanate and polycarbonate diol as polyol are obtained as essential raw materials, and the curing agent is an isocyanate group reactive compound, diol, polyether polyol, and glycerin propylene oxide Two-component thermosetting that can exhibit excellent performance such as mechanical strength (tensile strength, elongation), low compressive strain, low rebound resilience, water resistance, etc. by using together three components of specific molecular weight range called adduct Type polyurethane elastomer composition is obtained It found that it is theft, which resulted in the completion of the present invention.

  That is, the present invention is a two-component thermosetting polyurethane elastomer composition in which a urethane prepolymer (A) having an isocyanate group at its terminal and a curing agent (B) are blended, wherein the urethane polymer (A) is a Diphenylmethane diisocyanate as isocyanate (a1) and polycarbonate diol as polyol (a2) are used as essential raw materials, and the curing agent (B) is a diol (b1) having a molecular weight in the range of 50 to 150, A polyether polyol (b2) having a number average molecular weight of 600 or more and less than 2000 and a propylene oxide adduct (b3) of glycerin having a number average molecular weight in the range of 200 to 400 are contained as essential components. b3) has no aromatic ring in the molecule, and (b3) ) A two-component thermosetting polyurethane elastomer composition comprising (b1) in the range of 20 to 60 parts by mass and (b3) in the range of 1 to 20 parts by mass with respect to 100 parts by mass. Is.

  In the present invention, an equivalent ratio of the isocyanate group of the urethane prepolymer (A) having an isocyanate group at the terminal and the active hydrogen-containing group of the curing agent (B) using the two-component thermosetting polyurethane elastomer composition [isocyanate] [Group / active hydrogen-containing group] in the range of 1.00 to 1.50. The present invention relates to an elastic molded article obtained by mixing, stirring, pouring into a mold, thermosetting and molding.

  The present invention also relates to a roll comprising the elastic molded body.

  The two-component thermosetting polyurethane elastomer composition of the present invention can exhibit excellent performance such as mechanical strength (tensile strength, elongation), low compressive strain, low rebound resilience, water resistance, etc., and elastic molding using the same. The body is useful for a wide range of applications such as rolls, tires, belts, hoses, pipes, tubes, nets, cushions, industrial parts, clothing materials, hygiene materials, sports equipment and the like.

≪Two-component thermosetting polyurethane elastomer composition≫
The two-component thermosetting polyurethane elastomer composition of the present invention includes a urethane prepolymer (A) having an isocyanate group at its terminal (hereinafter also referred to as “urethane prepolymer (A)”) and a curing agent (B). It becomes.

  The urethane prepolymer (A) can be obtained by a known method using diphenylmethane diisocyanate as the specific polyisocyanate (a1) and polycarbonate diol as the specific polyol (a2).

  The curing agent (B) referred to in the present invention is a diol (b1) having a molecular weight in the range of 50 to 150 and a polyether polyol (b2) having a number average molecular weight (hereinafter referred to as “Mn”) of 600 or more and less than 2000. ), And a propylene oxide adduct (b3) of glycerin having a Mn in the range of 200 to 400 as an essential component, and all of the (b1) to (b3) have an aromatic ring in the molecule. And a compound having good reactivity with respect to the isocyanate group of the urethane prepolymer (A) (hereinafter also referred to as “isocyanate group-reactive compound”).

  The compounding ratio of the urethane prepolymer (A) as the main agent and the curing agent (B) ranges from 20 to 70 parts by mass of the curing agent (B) with respect to 100 parts by mass of the urethane prepolymer (A). Preferably, it is the range of 30-50. If the curing agent (B) is used in such a range, excellent performances such as mechanical strength, low compression strain, low rebound resilience, and water resistance can be obtained.

≪ (A) Urethane prepolymer having an isocyanate group at the terminal≫
The urethane prepolymer (A) used in the present invention was synthesized by a known method using diphenylmethane diisocyanate as the specific polyisocyanate (a1) and polycarbonate diol as the specific polyol (a2) as essential raw materials. The synthesis method is not particularly limited.

  Examples of the diisocyanate diisocyanate (hereinafter referred to as MDI) as the polyisocyanate (a1) include 4,4′-diphenylmethane diisocyanate (hereinafter referred to as 4,4′MDI), 2,4′-diphenylmethane diisocyanate, 2, 2'-diphenylmethane diisocyanate, and mixtures of these diphenylmethane diisocyanate isomers in any ratio, MDI dimer, carbodiimidized MDI, polyphenylpolymethylene polyisocyanate (hereinafter referred to as polymeric MDI), and the like. Among these, the required performance 4,4′MDI is preferred for the expression of.

  In the present invention, other polyisocyanates may be used in combination with the MDI as long as the object of the present invention is not impaired.

  The other polyisocyanate is not particularly limited as long as it is a polyisocyanate generally used in the production of polyurethane, and can be used as long as the object of the present invention is not impaired. For example, two isocyanate groups per molecule. Examples thereof include aromatic, aliphatic, and alicyclic polyisocyanates. These polyisocyanates may be used alone or in combination of two or more.

  Specifically, examples of the aromatic polyisocyanate include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and isomer mixtures of these tolylene diisocyanates (for example, 2,4 / 2 / 2,6). Body = 80/20 mass ratio mixture (TDI-80 / 20), 2,4 body / 2,6 body = 65/35 mass ratio mixture (TDI-65 / 35)), toluylene diisocyanate, xylylene diene Examples include isocyanate, paraphenylene diisocyanate, and naphthalene diisocyanate.

  Examples of the aliphatic polyisocyanate include ethylene diisocyanate, 1,4-butane diisocyanate, 1,6-hexane diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 2,2,4-trimethylhexane diisocyanate, and lysine. Diisocyanate etc. are mentioned.

  Examples of the alicyclic polyisocyanate include isophorone diisocyanate, norbornane diisocyanate, dicyclohexylmethane diisocyanate, cyclohexylene diisocyanate, and methylcyclohexylene diisocyanate.

  Furthermore, modified isocyanates such as urethane-modified products, biuret-modified products, allophanate-modified products, carbodiimide-modified products, burette-modified products, and isocyanurate-modified products of these polyisocyanates can also be used.

  In the present invention, polycarbonate diol is essentially used as the polyol (a2) constituting the urethane prepolymer (A).

  By using a polycarbonate diol as the polyol (a2) as an essential component, the elastic molded body obtained using the two-component thermosetting polyurethane elastomer composition of the present invention has excellent water resistance and mechanical strength (tensile strength, elongation). Can be granted.

  As the polyol (a2), instead of polycarbonate diol, for example, a polycarbonate polyol such as a mixture of polycarbonate polyol and polycaprolactone polyol or poly (carbonate / caprolactone) polyol may be used.

  The polycarbonate polyol preferably has a Mn in the range of 500 to 2000. For example, a dealcoholization condensation reaction between glycols and dialkyl carbonates such as dimethyl and diethyl, or a dephenol condensation reaction between glycols and diphenyl carbonate, or glycols. And those obtained by deethylene glycol condensation reaction of ethylene carbonate, diethyl carbonate and the like. Examples of the glycols include 1,6-hexanediol (1,6-HG), diethylene glycol, propylene glycol, 1,4-butanediol, 3-methyl-1,5-pentanediol, neopentyl glycol (NPG). ), Or alicyclic diols such as 1,4-cyclohexanediol and 1,4-cyclohexanedimethanol. Further, for example, poly (hexamethylene carbonate) polyol obtained by condensation reaction of 1,6-HG and diethyl carbonate can also be used. Examples of commercially available products include Nipponran 981 (trademark, manufactured by Nippon Polyurethane Co., Ltd., 1,6-HG type polycarbonate diol).

  The polycaprolactone polyol preferably has a Mn in the range of 500 to 2000, for example, α-caprolactone, β-caprolactone, γ-caprolactone, δ-caprolactone, α-methyl-ε-caprolactone, β-methyl-ε. -Lactones such as caprolactone and ethylene glycol, propylene glycol, 1,4-butanediol, 1,5-pentanediol, 3-methyl-1,5-pentanediol, 1,6-HG, NPG, diethylene glycol, 1, It can be obtained by reaction with 4-cyclohexanediol, 1,4-cyclohexanedimethanol, decamethylene glycol, polyethylene glycol, polytetramethylene glycol or the like.

  Furthermore, a lactone polyester polyether polyol can also be used. This can be obtained by performing a ring-opening addition polymerization reaction of a lactone with a polyol having two or more active hydrogen groups in the presence of a catalyst, and subsequently adding an alkylene oxide in the presence of a catalyst. As the polyol or lactone, the compound used to obtain polycaprolactone polyol can be used. Examples of the catalyst include alkali metals such as lithium, sodium, and potassium, hydroxides thereof, alcoholates, and the like, which can be used alone or as a mixture of two or more.

  The poly (carbonate / caprolactone) polyol preferably has a Mn in the range of 500 to 2000, transesterification reaction between polycarbonate polyol and polycaprolactone polyol, reaction between polycarbonate polyol and lactone, polycarbonate polyol / polycaprolactone) The polyol can be obtained by a method or the like by reacting in the presence of the lactones and / or the carbonate polyol.

  In the present invention, in the polyol (a2), a polycarbonate diol is essentially used. However, as other polyols, for example, polyols other than polycarbonate diols such as polyether polyols and polyester polyols may be used as long as the object of the present invention is not impaired. Can be used together.

  The urethane prepolymer (A) can be produced by reacting the isocyanate group of the polyisocyanate (a1) by a known method at an equivalent ratio in which the isocyanate group of the polyisocyanate (a1) is excessive with respect to the hydroxyl group of the polyol (a2). .

  In the synthesis reaction of the urethane prepolymer (A), the equivalent ratio of the isocyanate group (NCO group) of the polyisocyanate (a1) to the hydroxyl group (OH group) of the polyol (a2), that is, [NCO group / OH The group] is preferably in the range of 2.30 to 8.00 equivalent ratio, more preferably in the range of 3.00 to 6.00.

  When synthesizing the urethane prepolymer (A), the reaction method of the polyisocyanate (a1) and the polyol (a2) is not particularly limited, and may be according to a conventional method. The reaction temperature at that time may be set in consideration of safety and product quality, and is not particularly limited, and is usually reacted at 70 to 90 ° C.

  In the urethane prepolymer (A), the isocyanate group equivalent and the unreacted diphenylmethane diisocyanate content are important.

  The isocyanate group equivalent of the urethane prepolymer (A) is preferably in the range of 250 to 1000, more preferably in the range of 300 to 600, and the unreacted diphenylmethane diisocyanate content in the urethane prepolymer (A) is It is in the range of 5 to 25% by mass.

  If the isocyanate group equivalent of the urethane prepolymer (A) is within the above range, and the unreacted diphenylmethane diisocyanate content in the urethane prepolymer (A) is within the above range, the urethane group in the elastic molded body. This is preferable because fluctuations in concentration and crosslink density are suppressed and required performance is stabilized.

  The “isocyanate group equivalent” (unit: g / mol) in the present invention is a value measured according to JIS K1603-2007 Plastic-Polyurethane Raw Material Aromatic Isocyanate Test Method Part 1: Determination of Isocyanate Group Content. is there.

  As a reaction method for obtaining the urethane prepolymer (A), for example, the polyol (a2) from which water has been removed is dropped, divided, or collectively into a polyisocyanate (a1) charged in a reaction vessel. And then reacting until the hydroxyl group of the polyol (a2) is substantially eliminated.

  In order to allow the reaction to proceed safely and normally while gently controlling the exotherm during the reaction, a charging method by dropping or dividing is preferred.

  The urethane prepolymer (A) is usually produced in the absence of a solvent, but may be produced by reacting in an organic solvent. When making it react in an organic solvent, what is necessary is just to use the organic solvent which does not inhibit reaction, for example, ethyl acetate, n-butyl acetate, methyl ethyl ketone, toluene etc. are mentioned. The organic solvent used for the reaction is desirably removed by an appropriate method such as heating under reduced pressure or distilling off the thin film during or after the reaction.

  The reaction conditions (temperature, time, pressure, etc.) of the urethane prepolymer (A) are not particularly limited as long as the reaction behavior and product quality can be normally controlled. Usually, it is preferable to carry out the reaction at a reaction temperature of 50 to 90 ° C. under a reaction time of 2 to 24 hours. The pressure may be normal pressure, pressurization, or reduced pressure.

  As the reaction method, for example, a known reaction method such as batch, semi-continuous or continuous can be selected, and is not particularly limited.

  Moreover, when manufacturing the said urethane prepolymer (A), a urethanation catalyst can be used as needed. The said catalyst can be suitably added in the arbitrary steps of a raw material preparation process and a reaction process. Moreover, the addition method of a catalyst is not specifically limited, such as lump, division | segmentation, and continuous.

  As the urethanization catalyst, known catalysts can be used, for example, nitrogen-containing compounds such as triethylamine, tributylamine, benzyldibutylamine, triethylenediamine, N-methylmorpholine; or titanium tetrabutoxide, dibutyltin oxide, dibutyltin dilaurate, Organometallic compounds such as tin 2-ethylcaproate, zinc naphthenate, cobalt naphthenate, zinc 2-ethylcaproate, molybdenum glycolate, potassium acetate, zinc stearate, tin octylate, dibutyltin dilaurate; or iron chloride, Examples include inorganic compounds such as zinc chloride.

  Usually, the reaction is preferably performed in an inert gas atmosphere such as nitrogen or argon, but may be performed in a dry air atmosphere or in a condition where moisture is not mixed, such as a sealed condition.

  Moreover, as melt viscosity in 80 degreeC measured based on JISK-7301 of the said urethane prepolymer (A), Preferably it is 500-2000 mPa * s, More preferably, it is 500-1800. If the melt viscosity of (A) is within such a range, excellent workability can be obtained.

≪ (B) Curing agent≫
Next, the curing agent (B) to be blended with the urethane prepolymer (A) having the isocyanate group at the terminal will be described below.

  The curing agent (B) is a diol (b1) having a molecular weight of 50 to 150, a polyether polyol (b2) having a Mn of 600 or more and less than 2000, and a propylene oxide adduct of glycerin having a Mn of 200 to 400. (B3) is included as an essential component, and all of the (b1) to (b3) do not have an aromatic ring in the molecule, and the isocyanate group included in the urethane prepolymer (A). It is a reactive compound (hereinafter referred to as “isocyanate group reactive compound”).

  Moreover, the said hardening | curing agent (B) has three types of hardening | curing agents with the said diol (b1), the said polyether polyol (b2), and the propylene oxide adduct (b3) of the said glycerol as these essential (b1). -(B3) is contained in the range of a specific compounding quantity.

  Generally used curing agents are solid, semi-solid or pasty at 20 ° C. and have no fluidity, but the curing agent (B) used in the present invention is liquid at 20 ° C. Is preferable because it has high fluidity and excellent workability.

  The diol (b1) having a molecular weight in the range of 50 to 150 may have a linear, branched or cyclic structure as long as it has no aromatic ring. For example, 1,4- Butanediol (molecular weight 90), 1,5-pentanediol (molecular weight 104), 3-methyl-1,2-cyclopentanediol (molecular weight 116), 3-methyl-1,5-pentanediol (molecular weight 118), 1 , 6-hexanediol (molecular weight 118), 1,4-cyclohexanediol (molecular weight 116), 1,7-heptanediol (molecular weight 132), 1,8-octanediol (molecular weight 146), cis-1,5-cyclo And octanediol (molecular weight 144), trans-1,2-cyclooctanediol (molecular weight 144), and the like. Solubility better butanediol with (molecular weight 90) is preferable.

  When the molecular weight of the diol (b1) exceeds 150, the solubility with each polyol tends to be poor.

  The blending amount of the diol (b1) is in the range of 20 to 60 parts by mass (b1) with respect to 100 parts by mass of the polyether polyol (b2). When the blending amount of (b1) is within such a range, excellent performances such as mechanical strength (tensile strength, elongation), compression set, and water resistance can be obtained. When the amount of (b1) is less than 20 parts by mass, the mechanical strength and water resistance tend to be insufficient, and when it exceeds 60 parts by mass, the mechanical strength tends to be inferior.

  Examples of the polyether polyol (b2) having Mn of 600 or more and less than 2000 include polyalkylene glycols such as polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. Among these, mechanical strength (tensile strength, Polytetramethylene glycol is preferred because it can more effectively impart excellent performance such as elongation), low compression strain, low resilience, and water resistance.

  When the Mn of the polyether polyol (b2) is 2000 or more, the viscosity of the melt at the time of molding becomes too high, the elasticity is relatively lowered, and the hardness decrease over time called “creep down”. Occurs and tends to be inferior in performance such as mechanical strength, compression set, impact resilience, and water resistance.

  Further, together with the (b1) and the (b2), a propylene oxide adduct (b3) of glycerin having a Mn in the range of 200 to 400 is used in combination, so that mechanical strength (tensile strength, elongation), low compression strain is obtained. Further, performance such as low resilience and water resistance can be further improved. When the Mn of (b3) is less than 200 or more than 400, it tends to be inferior in performance such as mechanical strength (tensile strength, elongation) and water resistance.

  As said propylene oxide adduct (b3) of glycerol, Preferably the 2-5 mol adduct of the propylene oxide of glycerol is mentioned.

  In the present invention, a propylene oxide adduct (b3) of glycerin having a molecular weight of 200 to 400, which is a trifunctional polyether polyol, is used as the curing agent (B), but instead of the (b3), for example, In the case of using an ethylene oxide adduct of trimethylolpropane or the like, since it has a primary hydroxyl group, gelation tends to occur quickly, and molding may be difficult.

  The blending amount of the propylene oxide adduct (b3) of glycerin is in the range of (b3) 1 to 20 parts by mass with respect to 100 parts by mass of the polyether polyol (b2). When the blending amount of (b3) is within such a range, excellent performances such as mechanical strength (tensile strength, elongation), compressive strain, rebound resilience, and water resistance can be obtained. When (b3) is less than 1 part by mass or not contained, the compression set and impact resilience deteriorate, and when it exceeds 20 parts by mass, the compression set improves, Insufficient physical strength may result in failure to achieve the object of the present invention.

≪Elastic molded body≫
Next, the elastic molded body obtained using the two-component thermosetting polyurethane elastomer composition of the present invention will be described below.

  The elastic molded body of the present invention can be obtained by injecting the two-component thermosetting polyurethane elastomer composition into a predetermined mold that has been preheated as necessary, and thermosetting and molding.

  The elastic molded body comprises a urethane prepolymer (A) having an isocyanate group at its terminal and a curing agent (B), an isocyanate group (hereinafter referred to as “NCO group”) of the urethane prepolymer (A), and the curing agent. The two-component thermosetting polyurethane elastomer is mixed and stirred in the range of [NCO group / active hydrogen-containing group] in the range of 1.00 to 1.50 equivalent ratio with the active hydrogen-containing group of (B). After preparing the composition, it can be immediately poured into a preheated mold and thermoset to form.

  The “active hydrogen-containing group” in the present invention means a functional group reactive with an isocyanate group, for example, a group having active hydrogen such as a hydroxyl group, an amino group, a carboxyl group, a mercapto group, Preferred are a hydroxyl group and an amino group, and more preferred is a hydroxyl group.

  The elastic molded body of the present invention can be obtained by a known method, and is not particularly limited. For example, the elastic molded body can be molded by the following series of steps (1) to (3).

  Step (1) The urethane prepolymer (A), the curing agent (B), and additives as described below which are optional components are stirred or mixed manually or with a mixer, and degassed by vacuum. A two-component thermosetting polyurethane elastomer composition is prepared.

  Step (2) Immediately, the two-component thermosetting polyurethane elastomer composition is poured into a pre-heated mold, and thermosetting is performed for a predetermined time under a set temperature condition.

  Step (3) The molded product after curing is taken out of the mold to obtain the desired elastic molded body.

  The mixing method of the said urethane prepolymer (A) and the said hardening | curing agent (B) can employ | adopt well-known methods, such as manual mixing and mechanical mixing, and is not specifically limited.

  The curing conditions (temperature, time, etc.) of the thermosetting treatment are not particularly limited, but are preferably 10 to 20 hours at 40 to 150 ° C, and more preferably 2 to 16 hours at 80 to 120 ° C.

  The mold to be used is preferably preheated, and the preheating temperature is not particularly limited, but is preferably 80 to 120 ° C.

  Further, when preparing the two-component thermosetting polyurethane elastomer composition by stirring and mixing the urethane prepolymer (A) and the curing agent (B), a vacuum defoaming treatment may be performed as necessary. .

  The two-component thermosetting polyurethane elastomer composition may contain, as an optional component, a known additive used for a normal elastomer composition (polyurethane raw material) as long as the object of the present invention is not impaired. .

  Examples of such additives include, but are not limited to, catalysts, plasticizers, antioxidants, defoaming agents, antifoaming agents, ultraviolet absorbers, reaction modifiers, reinforcing agents, fillers, colorants (dyes or pigments). ), Mold release agents, stabilizers, light stabilizers, electrical insulation improvers, antistatic agents, fungicides, organic acid metal salts, waxes (amides, etc.), metal oxides, metal hydroxides, etc. Well-known things, such as a bulking agent, are mentioned.

  Examples of the elastic molded body of the present invention include various rolls that can be used in various printing such as gravure printing, flexographic printing, offset printing, etc., tires, belts, hoses, pipes, etc. Various molded products such as tubes, nets, cushions, industrial parts, clothing materials, sanitary materials, sporting goods and the like.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited to only these examples.

[Measuring method of melt viscosity of urethane prepolymer (A) having an isocyanate group at its end]
The melt viscosity (mPa · s, measurement temperature: 80 ° C.) of each urethane prepolymer (A) obtained in Examples and Comparative Examples was measured according to JIS K using a B-type viscometer (manufactured by Tokyo Keiki Co., Ltd., model: BM). Measured according to -7301. Hereinafter, the unit and measurement temperature are omitted.

[Method for measuring hardness of elastic molded body]
Using the two-component thermosetting polyurethane elastomer composition obtained in the examples and comparative examples, a right circular cylinder shape having a thickness of 12.5 ± 0.5 mm and a diameter of 29.0 ± 0.5 mm was prepared, and JIS K7312 It was measured using a JIS A type hardness meter (manufactured by Kobunshi Keiki Co., Ltd.) according to “Physical test method of thermosetting polyurethane elastomer molded product”.

[Measuring method and criteria for mechanical strength (tensile strength, elongation)]
A dumbbell-shaped test piece (No. 3 type test piece) was prepared from a sheet-like molded product (thickness 2 mm) obtained using the two-component thermosetting polyurethane elastomer composition obtained in Examples and Comparative Examples, and JIS K A tensile test was performed in accordance with -7312 to measure mechanical strength (tensile strength, elongation).
The determination of the measurement result was performed according to the following criteria.
Good (O): When the tensile strength is 40 MPa or more and the elongation is 300% or more.
Defect (x): When the tensile strength is less than 40 MPa or the elongation is less than 300%.

[Test method and criteria for compression set]
Using the two-component thermosetting polyurethane elastomer composition obtained in the examples and comparative examples, a right circular cylinder having a thickness of 12.5 ± 0.5 mm and a diameter of 29.0 ± 0.5 mm was prepared, and JIS K- In accordance with 7312, compression set was measured under the conditions of a compression rate of 25% and 70 ° C. × 22 hours.
The determination of the measurement result was performed according to the following criteria.
Excellent (◎): compression set is 30% or less.
Good (◯): compression set is 30% or more and less than 50%.
Defect (x): compression set is 50% or more.

[Test method and criteria for impact resilience]
Using the two-component thermosetting polyurethane elastomer composition obtained in the examples and comparative examples, a right circular cylinder having a thickness of 12.5 ± 0.5 mm and a diameter of 29.0 ± 0.5 mm was prepared, and JIS K- The rebound resilience was measured according to 7312.
The determination of the measurement result was performed according to the following criteria.
Good (O): Rebound elastic modulus is 25% or less.
Defect (x): Rebound resilience exceeds 25%.

[Water resistance test method and criteria]
A dumbbell-shaped test piece (No. 3 type test piece) was prepared from a sheet-like molded product (thickness 2 mm) obtained using the two-component thermosetting polyurethane elastomer composition obtained in Examples and Comparative Examples, and the temperature was 70 ° C. After impregnating with warm water for 4 weeks, a tensile test was carried out according to JIS K-7312.
Evaluation was based on the rate of change in mechanical strength (tensile strength, elongation) by tensile tests before and after the water resistance test.
Change rate of mechanical strength (tensile strength, elongation) (%) = [(tensile test value after water resistance test) ÷ (tensile test value before water resistance test) −1] × 100
The determination of the measurement result was performed according to the following criteria.
Good (O): When the tensile change rate is 10% or less and the elongation change rate is 10% or less.
Defect (x): When the tensile strength change rate exceeds 10% or the elongation change rate exceeds 10%.

[Example 1]
In a reaction vessel, 450 parts by mass of 4,4′-diphenylmethane diisocyanate (hereinafter abbreviated as “4,4′MDI”) in a molten state as polyisocyanate (a1) was placed and stirring was started. Next, 550 parts by mass of NIPPOLAN 981 (trademark, manufactured by Nippon Polyurethane Co., Ltd., 1,6-hexanediol type polycarbonate diol) is added and mixed as the polyol (a2), and the reaction is performed at 80 ° C. for 5 hours under a nitrogen stream. The melt viscosity is 1800 mPa · s (measurement method: JIS K-7301, measurement temperature: 80 ° C.), the isocyanate group equivalent (hereinafter abbreviated as “NCO group equivalent”) is 400, and the unreacted MDI content is The urethane prepolymer (A-1) which is 16.0 mass% was obtained.
In another container, 1,4-butanediol (molecular weight 90, hereinafter abbreviated as “1,4BG”) as the diol (b1), and polytetramethylene glycol (hereinafter ““ 4,4 ”) as the polyether polyol (b2). PTMG1000 ”), and trifunctional propylene glycol (commercial product, molecular weight of 250, hereinafter abbreviated as“ trifunctional PPG-250 ”) as propylene oxide adduct (b3) of glycerin (b1) / (b2 ) / (B3) = 40/100/5 parts by mass to adjust the curing agent (B-1).
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-1) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after the injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours. Sheet-like molded product) was obtained.
As shown in Table 1, the elastic molded body 1 of the present invention has a JIS A hardness of 90, and has excellent performance such as mechanical strength (tensile strength, elongation), compressive strain, impact resilience, and water resistance. Was.

[Example 2]
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trifunctional PPG-250 as propylene oxide adduct (b3) of glycerin (b1) / (b2) / ( b3) The curing agent (B-2) was prepared by mixing at a ratio of 40/100/10 parts by mass.
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-2) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after the injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours. A sheet molded product was obtained.
As shown in Table 1, the elastic molded body 2 of the present invention has a JIS A hardness of 90, and has excellent performance such as mechanical strength (tensile strength, elongation), compressive strain, impact resilience, and water resistance. Was.

Example 3
In a reaction vessel, 486 parts by mass of 4,4′MDI in a molten state as polyisocyanate (a1) was placed and stirring was started. Next, 514 parts by mass of NIPPOLAN 981 as the polyol (a2) was added and mixed, reacted at 80 ° C. under nitrogen flow for 5 hours, melt viscosity was 640 mPa · s, NCO group equivalent was 350, unreacted MDI A urethane prepolymer (A-2) having a content of 21.0% by mass was obtained.
In a separate container, as in Example 2, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trifunctional PPG-250 as propylene oxide adduct (b3) of glycerin (b1) The curing agent (B-2) was prepared by mixing at a ratio of / (b2) / (b3) = 40/100/10 parts by mass.
Next, in the compounding container, the urethane prepolymer (A-2) and the curing agent (B-2) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after the injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours. A sheet molded product was obtained.
As shown in Table 1, the elastic molded body 3 of the present invention has a JIS A hardness of 95, and has excellent performance such as mechanical strength (tensile strength, elongation), compressive strain, impact resilience, and water resistance. Was.

Example 4
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In another container, 1,4BG as the diol (b1), polytetramethylene glycol (hereinafter abbreviated as “PTMG650”) as the polyether polyol (b2), and a propylene oxide adduct (b3) of glycerin. The trifunctional PPG-250 was mixed at a ratio of (b1) / (b2) / (b3) = 40/100/10 parts by mass to prepare the curing agent (B-3).
Next, the urethane prepolymer (A-1) and the curing agent (B-3) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio in a blending container, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after the injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours. Sheet-like molded product) was obtained.
As shown in Table 1, the elastic molded body 4 of the present invention has a JIS A hardness of 89 and has excellent performance such as mechanical strength (tensile strength, elongation), compressive strain, impact resilience, and water resistance. Was.

[Comparative Example 1]
In a reaction vessel, 226 parts by mass of 2,4-toluene diisocyanate (hereinafter abbreviated as “2,4TDI”) in a molten state as polyisocyanate was placed and stirring was started. Next, 774 parts by mass of PTMG1000 as a polyol is added and mixed, and the reaction is performed at 70 ° C. for 5 hours under a nitrogen stream. The urethane prepolymer (A-3) has a melt viscosity of 910 mPa · s and an NCO group equivalent of 950. Got.
Next, in the compounding container, molten 3,3′-dichloro-4,4′-diaminodiphenylmethane (MBOCA) is used as the urethane prepolymer (A-3) and the aromatic amine curing agent (B ′) [NHOCA]. ₂ groups / NCO groups] = 0.90 equivalent ratio, and the mixture was poured into a mold preheated to 80 ° C. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours to form an elastic molded body 5 (cylindrical molded product and sheet molded product). )
As shown in Table 2, the elastic molded body 5 was inferior in mechanical strength, rebound resilience, and water resistance.

[Comparative Example 2]
Comparative Example 2 is an experiment using trimethylolpropane ethylene oxide 3 mol adduct (b4) instead of the glycerin propylene oxide adduct (b3), which is one of the essential components of the curing agent (B). is there.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as the diol (b1), PTMG1000 as the polyether polyol (b2), and TMP-30 (b4) (trademark, manufactured by Nippon Emulsifier Co., Ltd., trimethylolpropane ethylene as the trifunctional polyether polyol. Oxide 3 mol adduct, molecular weight 270.) was mixed at a ratio of (b1) / (b2) / (b4) = 40/100/5 parts by mass to prepare a curing agent (B-4).
Next, the urethane prepolymer (A-1) and the curing agent (B-4) were stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio in the compounding container, but the gelation proceeded quickly. It was too much to be molded, and the elastic molded body 6 could not be obtained.

[Comparative Example 3]
Comparative Example 3 is an experiment using trimethylolpropane (b5), which is a trifunctional glycol, instead of the glycerin propylene oxide adduct (b3), which is one of the essential components of the curing agent (B).
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trimethylolpropane (hereinafter abbreviated as “TMP”) (b5) as trifunctional glycol (b1) The curing agent (B-5) was prepared by mixing at a ratio of / (b2) / (b5) = 40/100/5 parts by mass.
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-5) were stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio. It was too much to be molded and the elastic molded body 7 could not be obtained.

[Comparative Example 4]
Comparative Example 4 is an experiment conducted without using the propylene oxide adduct (b3) of glycerin, which is one of the essential components of the curing agent (B).
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as the diol (b1) and PTMG1000 as the polyether polyol (b2) were mixed at a ratio of (b1) / (b2) = 40/100 parts by mass to obtain a curing agent (B-6 ) Was adjusted.
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-6) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then after-cured at 110 ° C. for 16 hours to form an elastic molded body 8 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 8 was inferior in mechanical strength, impact resilience, and water resistance.

[Comparative Example 5]
Comparative Example 5 is an experiment in which the content of the diol (b1), which is one of the essential components of the curing agent (B), is too small.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trifunctional PPG-250 as propylene oxide adduct (b3) of glycerin (b1) / (b2) / ( b3) was mixed at a ratio of 15/100/10 parts by mass to prepare the curing agent (B-7).
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-7) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours to form an elastic molded body 9 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 9 was inferior in mechanical strength and water resistance.

[Comparative Example 6]
Comparative Example 6 is an experiment in which the content of the diol (b1), which is one of the essential components of the curing agent (B), is excessive.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trifunctional PPG-250 as propylene oxide adduct (b3) of glycerin (b1) / (b2) / ( b3) = 65/100/10 The mixture was mixed at a ratio of 65 parts by mass to prepare the curing agent (B-8).
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-8) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours to form an elastic molded body 10 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 10 was inferior in mechanical strength.

[Comparative Example 7]
Comparative Example 7 is an experiment in which the content of the propylene oxide adduct (b3) of glycerin having a molecular weight of 200 to 400, which is one of the essential components of the curing agent (B), is excessive.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as diol (b1), PTMG1000 as polyether polyol (b2), and trifunctional PPG-250 as propylene oxide adduct (b3) of glycerin (b1) / (b2) / The curing agent (B-9) was prepared by mixing at a ratio of (b3) = 40/100/25 parts by mass.
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-9) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then further cured at 110 ° C. for 16 hours to form an elastic molded body 11 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 11 was inferior in mechanical strength.

[Comparative Example 8]
In Comparative Example 8, instead of the propylene oxide adduct (b3) of glycerin having a molecular weight of 430, which is one of the essential components of the curing agent (B), a propylene oxide adduct (b6) of glycerin having a molecular weight of 430 is used. This is the experiment used.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as the diol (b1), PTMG1000 as the polyether polyol (b2), and trifunctional propylene glycol as the propylene oxide adduct (b6) of glycerin (commercial product, molecular weight 430, hereinafter "3 (Abbreviated as “functional PPG-430”) was mixed at a ratio of (b1) / (b2) / (b6) = 40/100/10 parts by mass to prepare a curing agent (B-10).
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-10) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then further cured at 110 ° C. for 16 hours to form an elastic molded body 12 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 12 was inferior in mechanical strength and water resistance.

[Comparative Example 9]
In Comparative Example 9, a polyether polyol (b7) having a number average molecular weight of 2000 or more was used instead of the polyether polyol (b2) having a number average molecular weight of 600 or more and less than 2000, which is one of the essential components of the curing agent (B). It is an experiment.
In the charging operation and the reaction operation using the same raw materials as in Example 1, an urethane prepolymer (A-1) having an NCO group equivalent of 400 and an unreacted MDI content of 16.0% by mass was obtained. .
In a separate container, 1,4BG as the diol (b1), polytetramethylene glycol having a number average molecular weight of 2000 (hereinafter referred to as “PTMG2000”) as the polyether polyol (b7), and a propylene oxide adduct (b3) of glycerin Trifunctional PPG-250 was mixed at a ratio of (b1) / (b7) / (b3) = 40/100/10 parts by mass to prepare the curing agent (B-11).
Next, in the compounding container, the urethane prepolymer (A-1) and the curing agent (B-11) are stirred and mixed at an [NCO group / OH group] = 1.05 equivalent ratio, and preheated to 80 ° C. The mixture was poured into a placed mold. Immediately after injection, the mold is covered, left in a dryer (internal temperature 80 ° C.) for 1 hour, and then aftercured at 110 ° C. for 16 hours to form an elastic molded body 13 (cylindrical molded product and sheet-shaped molding). Product).
The elastic molded body 13 exhibited a decrease in hardness (creep down) over time when measuring the hardness, and was inferior in performance such as mechanical strength, compression set, rebound resilience, and water resistance.

The abbreviations or product names listed in Tables 1 and 2 mean the following.
4,4′MDI: 4,4′-diphenylmethane diisocyanate 1,6HG: 1,6-hexanediol 1,4BG: 1,4-butanediol PTMG2000: polytetramethylene glycol (having a number average molecular weight of 2000)
PTMG1000: polytetramethylene glycol (number average molecular weight 1000)
PTMG650: Polytetramethylene glycol (number average molecular weight 650)
PPG-430: Trifunctional propylene glycol (number average molecular weight 430)
PPG-250: Trifunctional propylene glycol (having a number average molecular weight of 250)
2,4TDI: 2,4-toluene diisocyanate MBOCA: 3,3′-dichloro-4,4′-diaminodiphenylmethane TMP: trimethylolpropane TMP-EO-30: trimethylolpropane EO 3 molar adduct, molecular weight 270.
Nipponporan 981: Trademark, manufactured by Nippon Polyurethane Co., Ltd., 1,6HG type polycarbonate diol

  The two-component thermosetting polyurethane elastomer composition of the present invention can exhibit excellent performance such as mechanical strength (tensile strength, elongation), low compressive strain, low rebound resilience, water resistance, etc., and elastic molding using the same. The body can be used for various types of printing such as gravure printing, flexographic printing, and offset printing (inking, ink kneading, ink application, etc.), tire, belt, hose, pipe, tube, net, cushion It is useful for a wide range of applications such as industrial parts, clothing materials, sanitary materials, and sporting goods.

Claims (5)

  A two-component thermosetting polyurethane elastomer composition comprising a urethane prepolymer (A) having an isocyanate group at its end and a curing agent (B), wherein the urethane polymer (A) is diphenylmethane as polyisocyanate (a1). It is obtained by using diisocyanate and polycarbonate diol as the polyol (a2) as essential raw materials. The curing agent (B) is a diol (b1) having a molecular weight in the range of 50 to 150, a number average molecular weight of 600 or more and 2000. Less than the polyether polyol (b2) and the propylene oxide adduct (b3) of glycerin having a number average molecular weight in the range of 200 to 400 as essential components, all of the (b1) to (b3) being in the molecule And (b2) 100 parts by mass To the (b1) 20 to 60 parts by weight range, the (b3) a two-liquid thermosetting type polyurethane elastomer composition, which comprises in the range of 1 to 20 parts by weight.   The isocyanate group equivalent of the urethane prepolymer (A) is in the range of 250 to 1000, and the unreacted diphenylmethane diisocyanate content in the urethane prepolymer (A) is in the range of 5 to 25% by mass. The two-component thermosetting polyurethane elastomer composition described.   The two-component thermosetting polyurethane elastomer composition according to claim 1, wherein the glycerin propylene oxide adduct (b3) is a 2 to 5 mol adduct of glycerin propylene oxide.   Using the two-component thermosetting polyurethane elastomer composition according to any one of claims 1 to 3, the isocyanate group of the urethane prepolymer (A) having an isocyanate group at the terminal and the active hydrogen of the curing agent (B) Elasticity characterized by being obtained by mixing, stirring, pouring into a mold, thermosetting and molding, within a range of equivalent ratio [isocyanate group / active hydrogen-containing group] to the containing group in the range of 1.00 to 1.50. Molded body.   A roll comprising the elastic molded body according to claim 4.