JP4677818B2 - Room temperature curable polyurethane resin composition - Google Patents

Description

  The present invention relates to a room temperature curable polyurethane resin composition.

  Since polyurethane has adhesiveness, flexibility, water resistance, etc., it is used for applications such as sealing materials, adhesives, coating materials, primers, and paints. For the purpose of providing a polyurethane resin composition having excellent adhesiveness, a polyurethane resin composition containing a compound having a silicon atom as in Patent Documents 1 to 4 has been proposed.

  Patent Document 1 describes a urethane-based adhesive composition containing an isocyanate alkoxysilane. Patent Document 2 describes a one-component moisture-curable urethane prepolymer composition in which an isocyanate-based silane coupling agent having functional groups of both an isocyanate group and a hydrolyzable silane group is blended with a urethane prepolymer. . Patent Document 3 describes a one-component moisture-curable polyurethane composition containing a compound having an isocyanate group and a hydrolyzable alkoxysilyl group and a urethane prepolymer. Patent Document 4 contains (A) a urethane prepolymer and the following (B) and / or (C), (B) is a silicate ester and / or a condensate thereof, and (C) is A one-component moisture-curable polyurethane resin composition, which is an inorganic filler surface-treated with (B), is described.

JP-A-2-279784 JP 2000-226424 A JP 2003-252949 A JP 2002-12645 A

However, the present inventor has found that the polyurethane composition containing a compound having a silicon atom as described in Patent Documents 1 to 4 has room for improvement in terms of adhesion.
In addition, the inventor of the present invention, in research for improving the adhesion of the polyurethane composition, a polyurethane composition containing a urethane prepolymer having an isocyanate group bonded to an aromatic ring, a ketimine, and an epoxy resin It was found that the adhesiveness is inferior. In this regard, the inventor found that such a urethane prepolymer is highly reactive, and the urethane prepolymer itself is moisture-cured faster than it reacts with ketimine in the presence of moisture, and ketimine may remain excessively. I guessed it was the cause.

  Accordingly, an object of the present invention is to provide a room temperature curable polyurethane resin composition having excellent adhesiveness.

  As a result of intensive investigations to achieve the above-mentioned problems, the present inventors added another urethane prepolymer, an epoxy resin, and an additive containing ketimine mixed in advance to a composition containing a urethane prepolymer. The inventors have found that the adhesiveness is excellent and have completed the present invention.

That is, the present invention provides the following (1) to ( 3 ).
(1) A room temperature curable polyurethane resin composition having a composition containing a urethane prepolymer A and an additive containing a urethane prepolymer B, an epoxy resin and a ketimine mixed in advance,
The amount of the additive is 1 to 50 parts by mass with respect to 100 parts by mass of the urethane prepolymer A,
The isocyanate group of the urethane prepolymer A is bonded to the aromatic ring,
The urethane prepolymer B can be obtained by reacting a polyisocyanate compound having a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms and a polycarbonate polyol, and a room temperature curable polyurethane resin. Composition.
(2) The room temperature curable type according to (1), wherein the ketimine has a structure in which a branched carbon atom or a ring member carbon atom is bonded to the α-position of at least one of a carbon atom and a nitrogen atom of a ketimine bond. Polyurethane resin composition.
(3) Room temperature curable polyurethane resin composition obtained by adding an additive containing urethane prepolymer B, epoxy resin and ketimine mixed in advance to a composition containing urethane prepolymer A. A method for producing a polyurethane resin composition, comprising:
The amount of the additive, with respect to the urethane prepolymer A100 parts by mass Ri 1 to 50 parts by mass der,
The isocyanate group of the urethane prepolymer A is bonded to the aromatic ring,
The urethane prepolymer B can be obtained by reacting a polyisocyanate compound having a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms and a polycarbonate polyol, and a room temperature curable polyurethane resin. A method for producing the composition.

  The room temperature curable polyurethane resin composition of the present invention is excellent in adhesiveness.

The present invention is described in detail below.
The room temperature curable polyurethane resin composition of the present invention comprises:
A room temperature curable polyurethane resin composition comprising a composition containing a urethane prepolymer A, and a premixed urethane prepolymer B, an epoxy resin and an additive containing a ketimine,
It is a room temperature curable polyurethane resin composition whose amount of the additive is 1 to 50 parts by mass with respect to 100 parts by mass of the urethane prepolymer A.

The composition containing the urethane prepolymer A will be described below.
Urethane prepolymer A is a reaction product obtained by reacting a polyol compound and a polyisocyanate compound, and is a polymer containing an isocyanate group at the molecular end.

  Examples of the urethane prepolymer A include those in which the isocyanate group of the urethane prepolymer A is bonded to an aromatic ring and bonded to an aliphatic hydrocarbon. Especially, it is preferable that the isocyanate group of the urethane prepolymer A has couple | bonded with the aromatic ring from a viewpoint of a cure rate, adhesiveness, and high intensity | strength.

  It is sufficient that at least one isocyanate group is bonded to one aromatic ring. The isocyanate group bonded to the aromatic ring is not particularly limited with respect to the substitution position and number. The aromatic ring can have a substituent in addition to the isocyanate group. There are no particular limitations on the type, position, and number of substituents.

  The urethane prepolymer A only needs to have at least one isocyanate group bonded to the aromatic ring, and one preferred embodiment is that all of the isocyanate groups of the urethane prepolymer A are bonded to the aromatic ring. .

  The urethane prepolymer in which the isocyanate group is bonded to the aromatic ring is not particularly limited for its production. For example, it can be obtained by reacting a polyisocyanate compound having an isocyanate group bonded to an aromatic ring with a polyol compound.

Examples of the polyisocyanate compound in which an isocyanate group is bonded to an aromatic ring include 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), 4, 4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 1,4-phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, tolidine diisocyanate (TODI), 1 , 5-naphthalene diisocyanate (NDI).
A polyisocyanate compound can be used individually or in combination of 2 types or more, respectively.

The polyol compound will be described below.
The polyol compound is not particularly limited, and examples thereof include polyether polyols, polyester polyols, acrylic polyols, polycarbonate polyols, other polyols, and mixed polyols thereof.

  Examples of the polyether polyol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, glycerin, 1,1,1-trimethylolpropane, 1,2,5-hexanetriol, 1,3-butanediol, 1, One or more polyhydric alcohols such as 4-butanediol, 4,4'-dihydroxyphenylpropane, 4,4'-dihydroxyphenylmethane, pentaerythritol, propylene oxide, ethylene oxide, butylene oxide, styrene Examples include polyether polyols obtained by adding one or more alkylene oxides such as oxides; polyether polyols obtained by ring-opening polymerization such as tetrahydrofuran.

  Specific examples of the polyether polyol include polytetramethylene glycol obtained by ring-opening polymerization of polyoxyethylene glycol, polyoxypropylene glycol, polyoxypropylene triol, and tetrahydrofuran.

  Examples of the polyester polyol include one or more low molecular polyols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, cyclohexanedimethanol, glycerin, and 1,1,1-trimethylolpropane. And a condensation polymer of glutaric acid, adipic acid, pimelic acid, suberic acid, sebacic acid, terephthalic acid, isophthalic acid and one or more of low molecular weight carboxylic acids and oligomeric acids; propionlactone, valerolactone , Ring-opening polymers of lactones such as caprolactone.

  Examples of the acrylic polyol include acrylic polyols that can be obtained from at least one selected from the group consisting of acrylic acid, methacrylic acid, methyl acrylate ethyl acrylate, methyl methacrylate, ethyl methacrylate, and β-hydroxyethyl methacrylate. It is done.

  Examples of the polycarbonate polyol include ethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1, One or more diols such as 9-nonanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, bisphenol A, dimethyl carbonate, diphenyl What can be obtained by making at least 1 sort (s) of carbonate, ethylene carbonate, and phosgene react is mentioned.

  Examples of other polyols include polymer polyols; polybutadiene polyols; hydrogenated polybutadiene polyols; and low molecular polyols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol, pentanediol, and hexanediol. .

  Among these, the polyoxypropylene glycol and the polyoxypropylene triol are preferable as the polyol compound as a raw material of the urethane prepolymer A from the viewpoint of easy molecular design.

Moreover, since the polyol compound has excellent physical properties after curing, a polyether polyol having a number average molecular weight of 1500 to 15000 is preferable, and a polyether polyol having 2000 to 10,000 is more preferable.
A polyol compound can be used individually or in combination of 2 types or more, respectively.

  The combination of a polyol compound and a polyisocyanate compound is not particularly limited. Each of the polyol compounds and each of the polyisocyanate compounds can be used in any combination. Specifically, for example, from at least one selected from the group consisting of polyoxyethylene glycol, polyoxypropylene glycol, and polyoxypropylene triol, and at least one selected from the group consisting of TDI and MDI The obtained urethane prepolymer is preferable from the viewpoint of physical property adjustment, cost, and availability.

  The mixing ratio of the polyol compound and the polyisocyanate compound is preferably such that the molar ratio (NCO / OH) of the isocyanate group in the polyisocyanate compound to the hydroxy group in the polyol compound is 1.3 to 2.5. More preferably, it is 5 to 2.0. In such a range, the viscosity of the urethane prepolymer is moderate and the elongation of the cured product is excellent.

  The reaction between the polyol compound and the polyisocyanate compound is not particularly limited. For example, the method of heating and stirring the polyol compound and polyisocyanate compound of the above-mentioned quantitative ratio at 50-100 degreeC is mentioned. If necessary, for example, a urethanization catalyst such as an organic tin compound, an organic bismuth, or an amine can be used.

  The urethane prepolymer A is preferably liquid at room temperature from the viewpoint of handling. In addition to the isocyanate group, the urethane prepolymer A can have groups such as a hydroxy group, an acid anhydride group, an amino group, a latent amino group, a mercapto group, and a carboxy group in the molecule. When having such a group that can be cross-linked by reacting with an isocyanate group, the crosslink density of the obtained cured product is improved and the physical properties are excellent.

  In the present invention, the composition containing the urethane prepolymer A may be composed only of the urethane prepolymer A, but in addition to the urethane prepolymer A, the compounding agent is added within a range not impairing the object of the present invention. Can be contained. Examples of the compounding agent include a curing agent, a curing catalyst, a filler, a plasticizer, an antioxidant, an anti-aging agent, an inorganic pigment, an organic pigment, an adhesion promoter, a flame retardant, a dehydrating agent, a solvent, a silane coupling agent, Examples include thixotropy imparting agents and antistatic agents. The amount of the additive is not particularly limited, and an amount that can be generally used in a urethane-based composition can be blended.

  The curing agent is not particularly limited as long as it has a functional group capable of reacting with an isocyanate group. For example, a polyamine compound having two or more amino groups in the molecule, a polyol compound having two or more hydroxy groups in the molecule. Is mentioned.

Examples of the polyamine compound include amine compounds having two amino groups in the molecule (aliphatic diamine, aromatic diamine, etc.), and amine compounds having three or more amino groups in the molecule.
Examples of the aliphatic diamine include ethylenediamine, 1,2-propanediamine, 1,3-propanediamine, 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, and 1,7-heptane. Diamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,12-dodecanediamine, 1,14-tetradecanediamine, 1,16-hexadecanediamine, hexamethylenediamine, trimethylhexamethylene Diamine, iminobispropylamine, methyliminobispropylamine, 1,5-diamino-2-methylpentane, isophoronediamine, 1,3-bisaminomethylcyclohexane, 1-cyclohexylamino-3-aminopropane, 3-aminomethyl -3,3,5-tri Chill - cyclohexylamine, norbornane diamine (NBDA), meta-xylylenediamine (MXDA) and the like.

  Examples of aromatic diamines include 4,4'-methylenebis (3-chloro-2,6-diethylaniline), 4,4'-methylenebis (2-chloroaniline) (MOCA), and 4,4'-diaminodiphenylmethane. 2,4'-diaminodiphenylmethane, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2'-diaminobiphenyl, 3,3'-diaminobiphenyl, 2,4-diaminophenol, 2, 5-diaminophenol, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 2,3-tolylenediamine, 2,4-tolylenediamine, 2,5-tolylenediamine, 2,6-tolylenediamine Examples include amines and 3,4-tolylenediamine.

  Examples of the amine compound having three or more amino groups in the molecule include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and pentaethylenehexamine.

  As a polyol compound which has two or more hydroxy groups in a molecule | numerator, the thing similar to the polyol compound currently used as a raw material of said urethane prepolymer A is mentioned, for example.

  Among these, 4,4′-methylenebis (3-chloro-2,6-diethylaniline), MOCA, polyoxypropylene glycol, and polyoxypropylene triol are preferable. A hardening | curing agent can be used individually or in combination of 2 or more types, respectively.

  The amount of the curing agent is preferably such that the molar ratio of the functional group capable of reacting with the isocyanate group in the curing agent with respect to the isocyanate group of the urethane prepolymer A is 0.7 to 1.3, 0.9 to 1.1 is more preferable. When the amount of the curing agent is within such a range, curing failure does not occur, an appropriate pot life can be obtained, and the elongation of the cured product obtained is excellent.

Examples of the curing catalyst include organometallic catalysts and tertiary amines.
Examples of the organometallic catalyst include dibutyltin dilaurate, dioctyltin laurate, zinc octylate, lead neodecanoate, lead octylate, cobalt octylate, and organic bismuth compounds.
Tertiary amines include trimethylamine, triethylamine, tributylamine, N, N-dimethylcyclohexylamine, N, N, N ′, N′-tetramethylethylenediamine, tetramethylguanidine, triethylenediamine, and N-methylmorpholine. .

  The curing catalysts can be used alone or in combination of two or more. The amount of the curing catalyst is preferably 0.03 to 3 parts by mass, and 0.1 to 1 part by mass with respect to 100 parts by mass of the urethane prepolymer A from the viewpoint of curability and pot life. More preferred.

  Examples of the filler include fumed silica, calcined silica, precipitated silica, ground silica, fused silica; diatomaceous earth; iron oxide, zinc oxide, titanium oxide, barium oxide, magnesium oxide; calcium carbonate, magnesium carbonate, zinc carbonate Waxy clay, kaolin clay, calcined clay; carbon black; and these fatty acids, resin acids, fatty acid esters, and urethane compound treated products.

  Examples of the plasticizer include diisononyl adipate, dioctyl adipate, dioctyl phthalate, dibutyl phthalate, butyl benzyl phthalate, isodecyl succinate, diethylene glycol dibenzoate, pentaerythritol ester, butyl oleate, methyl acetylricinoleate, phosphorus Examples include tricresyl acid, trioctyl phosphate, propylene glycol adipate polyester, and butylene glycol polyester adipate.

Examples of the antioxidant include butylhydroxytoluene, butylhydroxyanisole, and triphenyl phosphite.
Examples of the antiaging agent include hindered phenol compounds, benzotriazole compounds, and hindered amine compounds.

Examples of inorganic pigments include titanium dioxide, zinc oxide, ultramarine, bengara, lithopone, lead, cadmium, iron, cobalt, aluminum, hydrochloride, and sulfate.
Examples of organic pigments include azo pigments and copper phthalocyanine pigments.
Examples of the adhesion imparting agent include terpene resin, phenol resin, terpene-phenol resin, rosin resin, and xylene resin.

Flame retardants include, for example, chloroalkyl phosphate, methylphosphonic acid dimethyl ester, bromine and / or phosphorus atom-containing compounds, ammonium polyphosphate, diethyl bishydroxyethyl aminoethyl phosphate, neopentyl bromide-polyether, brominated poly Ether.
Examples of the dehydrating agent include acyloxysilyl group-containing polysiloxane.

  The composition containing the urethane prepolymer A is not particularly limited for its production. For example, in the case of a one-pack type, the urethane prepolymer A and a compounding agent used as necessary can be dried well and mixed under conditions where moisture is removed. The obtained composition containing the one-component urethane prepolymer A is preferably stored in a container that does not receive moisture.

  When the composition containing the urethane prepolymer A is to be a two-part type, for example, a two-part type is prepared by respectively preparing a first liquid containing the urethane prepolymer A and a second liquid containing a curing agent. It can be set as the composition containing the urethane prepolymer A. A compounding agent other than the curing agent can be added to the first liquid and / or the second liquid, and at least one of them is preferably added to the first liquid. The composition containing the two-pack type urethane prepolymer A can store the first liquid and the second liquid in separate containers.

The additive will be described below.
The additive contains urethane prepolymer B, epoxy resin, and ketimine mixed in advance, and the amount of the additive is 1 to 50 parts by mass with respect to 100 parts by mass of urethane prepolymer A.

  The urethane prepolymer B is a reaction product obtained by reacting a polyol compound and a polyisocyanate compound, and is a polymer containing an isocyanate group at the molecular end.

  Examples of the urethane prepolymer B include a urethane prepolymer having an isocyanate group bonded to a tertiary carbon atom, a urethane prepolymer having an isocyanate group bonded to a secondary carbon atom, and a primary carbon atom. And a urethane prepolymer having an isocyanate group bonded to. Among these, a urethane prepolymer having an isocyanate group bonded to a tertiary carbon atom is preferred from the viewpoint that storage stability and reaction rate can be slowed. The isocyanate group bonded to the tertiary carbon atom has a large steric hindrance around the isocyanate group and a low reactivity. For this reason, urethane prepolymers with isocyanate groups attached to tertiary carbon atoms react gently with amines produced by the hydrolysis of ketimines, so epoxy resins are produced by the hydrolysis of ketimines. Can react with amines.

  The urethane prepolymer having an isocyanate group bonded to a tertiary carbon atom is not particularly limited for its production. For example, the urethane prepolymer which can be obtained by reaction of the polyisocyanate compound which has the isocyanate group couple | bonded with the tertiary carbon atom, and a polyol compound is mentioned.

  The polyisocyanate compound having an isocyanate group bonded to a tertiary carbon atom can be specifically represented by the following formula (1).

In the formula, R ^a , R ^b and R ^c are each independently an organic group optionally containing O, S and N, and p is an integer of 1 or more.

Examples of the organic group include an alkyl group, a cycloalkyl group, an aryl group, and an aralkyl group. The organic group can include, for example, a functional group such as a carbonyl group, a urea group (carbamide group) or an isocyanate group; a bond such as an ether bond, an amide bond or a urethane bond.
The organic group represented by R ^a or R ^b is preferably an alkyl group or a cycloalkyl group. As the alkyl group, for example, an alkyl group having 1 to 5 carbon atoms is preferable, and specific examples include a methyl group, an ethyl group, a propyl group, and an isopropyl group. Examples of the cycloalkyl group include a cyclopentyl group and a cyclohexyl group. Among these, one preferred embodiment is that R ^a and R ^b are methyl groups.

One preferred embodiment of R ^c is an aryl group. Examples of the aryl group include a phenyl group; a group obtained by removing at least one hydrogen atom from a condensed polycyclic hydrocarbon such as naphthalene and anthracene; and at least one hydrogen atom from a heterocyclic ring such as furan, thiophene, pyrrole, and pyridine. Examples include groups that have been removed. The aryl group is a phenyl group, which is one of preferred embodiments from the viewpoint of strength and adhesiveness. The aryl group can have a substituent in addition to the tertiary carbon atom to which the isocyanate group is bonded. There are no particular limitations on the type, position, and number of substituents.

p is an integer of 1 or more, and is preferably an integer of 2 or more. In addition, when p is 1, the polyisocyanate compound represented by the formula (1) may contain one or more isocyanate groups in at least one organic group of R ^a , R ^b and R ^c. it can.

  From the viewpoint of reaction rate, the polyisocyanate compound preferably has a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms.

  Examples of the polyisocyanate compound include polyisocyanate compounds such as m- or p-tetramethylxylylene diisocyanate (TMXDI), isophorone diisocyanate (IPDI), hydrogenated MDI, and hydrogenated TDI represented by the formula (2); Examples include isocyanurate bodies and burette bodies of these polyisocyanate compounds; adducts of these polyisocyanate compounds and polyhydric alcohols such as 1,1,1-trimethylolpropane.

  Examples of the adduct of a polyisocyanate compound and a polyhydric alcohol are represented by the formula (3) that can be obtained from m-tetramethylxylene diisocyanate (TMXDI) and 1,1,1-trimethylolpropane (TMP). Adducts.

  The adduct may contain an unreacted polyisocyanate compound and / or a polyhydric alcohol.

  The polyisocyanate compound is preferably m- or p-tetramethylxylylene diisocyanate or IPDI represented by the formula (2) from the viewpoint of excellent adhesion, storage stability, and reaction rate. A polyisocyanate compound can be used individually or in combination of 2 types or more, respectively.

The polyol compound will be described below.
Examples of the polyol compound include polyether polyol, polyester polyol, acrylic polyol, polycarbonate polyol, other polyols, and mixed polyols thereof. Specific examples thereof are the same as the polyol compound as a raw material of the urethane prepolymer A described above.

  A polyol compound can be used individually or in combination of 2 types or more, respectively.

  As a combination of a polyisocyanate compound and a polyol compound, from the viewpoint of heat resistance and adhesiveness, a polyisocyanate compound having a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms, polycarbonate polyol, A urethane prepolymer that can be obtained by reacting is preferred. Specifically, urethane prepolymers that can be obtained from TMXDI and polycarbonate polyol, and urethane prepolymers that can be obtained from TMXDI, polycarbonate polyol, and 1,1,1-trimethylolpropane can be mentioned as preferred embodiments.

  The mixing ratio of the polyol compound and the polyisocyanate compound is preferably such that the molar ratio (NCO / OH) of the isocyanate group in the polyisocyanate compound to the hydroxy group in the polyol compound is 1.3 to 2.5. More preferably, it is 5 to 2.0. When it is in this range, the viscosity of the urethane prepolymer is moderate and the elongation of the cured product is excellent.

  The reaction between the polyol compound and the polyisocyanate compound is not particularly limited. For example, the method of heating and stirring the polyol compound and polyisocyanate compound of the above-mentioned quantitative ratio at 50-100 degreeC is mentioned. If necessary, for example, a urethanization catalyst such as an organic tin compound, an organic bismuth, or an amine can be used.

The urethane prepolymer B is preferably liquid at room temperature from the viewpoint of handling. In addition to the isocyanate group, the urethane prepolymer B can have, in the molecule, groups such as a hydroxy group, an acid anhydride group, an amino group, a latent amino group, a mercapto group, and a carboxy group. When having such a group that can be cross-linked by reacting with an isocyanate group, the crosslink density of the obtained cured product is improved and the physical properties are excellent.
Urethane prepolymer B can be used alone or in combination of two or more.

The epoxy resin will be described below.
The epoxy resin is not particularly limited. For example, an epoxy resin having a bisphenyl group such as bisphenol A type, bisphenol F type, brominated bisphenol A type, hydrogenated bisphenol A type, bisphenol S type, bisphenol AF type, or biphenyl type. Compound, polyalkylene glycol type, alkylene glycol type epoxy compound, epoxidized resin having naphthalene ring, bifunctional glycidyl ether type epoxy resin such as epoxy compound having fluorene group; phenol novolak type, orthocresol novolak type, Trifunctional or higher glycidyl ether type epoxy resin such as DPP novolac type, trishydroxyphenylmethane type, tetraphenylolethane type; glycidyl ester type epoxy of synthetic fatty acid such as dimer acid Fats; N, N, N ′, N′-tetraglycidyldiaminodiphenylmethane (TGDDM), triglycidyl isocyanurate, tetraglycidyl-m-xylylenediamine, N, N-diglycidylaniline, triglycidyl-p-aminophenol Such a glycidylamino type epoxy resin is mentioned.

  Among them, it is preferable to use an epoxy resin having an aromatic ring in the skeleton because of high heat resistance. The epoxy resin is preferably in a liquid state from the viewpoint of handling. An epoxy resin can be used individually or in combination of 2 types or more, respectively.

  The quantitative ratio between the urethane prepolymer B and the epoxy resin is preferably 70/30 to 30/70, and more preferably 60/40 to 40/60. In such a range, the adhesiveness is more excellent.

Ketimine is described below.
Ketimine is a compound that can generate primary amines by hydrolysis. The ketimine used is not particularly limited. In the present invention, a compound having a C═N bond (ketimine bond) derived from a ketone or aldehyde and an amine is referred to as ketimine. Therefore, in the present invention, ketimine includes aldimine having a —HC═N bond.

  Examples of the ketimine include those having a structure in which a branched carbon atom or a ring member carbon atom is bonded to the α-position of at least one of the carbon atom and nitrogen atom of the ketimine bond. As a ring member carbon atom, the carbon atom which comprises an aromatic ring and the carbon atom which comprises an alicyclic ring are mentioned, for example.

  Examples of ketimines include (1) ketimines that are reaction products of polyamines and carbonyl compounds, and (2) silicon-containing ketimines that are reaction products of aminoalkoxysilanes and carbonyl compounds.

  The carbonyl compound that is a raw material of ketimine is preferably a ketone or aldehyde having a substituent at the α-position carbon atom of the carbonyl carbon atom because of excellent balance between storage stability and curing rate. Examples of such ketones or aldehydes include compounds represented by the following formula (4).

In Formula (4), R ¹ is a hydrogen atom or a methyl group, R ² is an alkyl group having 1 to 6 carbon atoms, R ³ is a methyl group or an ethyl group, and R ⁴ is a hydrogen atom or a methyl group. Or it is an ethyl group.

Examples of the alkyl group having 1 to 6 carbon atoms of R ² include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, n- Examples include pentyl group, isopentyl group, t-pentyl group, neopentyl group, n-hexyl group, and isohexyl group.

R ² can combine with R ¹ or R ³ to form a ring structure. Examples of the ring structure when R ² is bonded to R ³ include cyclopentane, cyclohexane, and cycloheptane. Examples of the ring structure when R ² is bonded to R ¹ include cyclopentanone, cyclohexanone, and cycloheptanone.

Examples of the compound represented by the formula (4) include ketones such as methyl isopropyl ketone (MIPK), methyl t-butyl ketone (MTBK), methyl isobutyl ketone (MIBK), methyl cyclohexyl ketone, and methylcyclohexanone; Aldehydes such as isopropyl aldehyde and isobutyraldehyde.
A carbonyl compound can be used individually or in combination of 2 types or more, respectively.

The polyamine which is a raw material of ketimine is not particularly limited as long as it has two or more amino groups. Of these, aliphatic polyamines are preferred from the viewpoint of excellent curing speed.
Examples of aliphatic polyamines include 2,5-dimethyl-2,5-hexamethylenediamine, mensendiamine, 1,4-bis (2-amino-2-methylpropyl) piperazine, and propylene branches at both molecular ends. Polypropylene glycol (PPG) with an amino group bonded to carbon, ethylenediamine, propylenediamine, butylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, hexamethylenediamine, trimethylhexamethylenediamine, N-aminoethylpiperazine , 1,2-diaminopropane, iminobispropylamine, polyether methyl iminobispropylamine, a methylene group to an amine nitrogen, such as _{H 2 N (CH 2 CH 2} O) 2 (CH 2) 2 NH 2 was bound Skeletal diamine, 1,5-diamino-2-methylpentane, metaxylylenediamine (MXDA), polyamidoamine, isophoronediamine, 1,3-bisaminomethylcyclohexane (1,3BAC), 1-cyclohexylamino-3- Examples include aminopropane, 3-aminomethyl-3,3,5-trimethyl-cyclohexylamine, and norbornanediamine (NBDA). Among these, norbornanediamine, 1,3-bisaminomethylcyclohexane, metaxylylenediamine, H ₂ N (CH ₂ CH ₂ O) ₂ (CH ₂ ) ₂ NH ₂ , and polyamidoamine are used because of their high curing speed. preferable.
Polyamines can be used alone or in combination of two or more.

Examples of ketimines that are a reaction product of a polyamine and a carbonyl compound include those obtained from MIPK or MTBK and H ₂ N (CH ₂ CH ₂ O) ₂ (CH ₂ ) ₂ NH ₂ , MIPK or MTBK and 1, Those obtained from 3-bisaminomethylcyclohexane, those obtained from MIPK, MIBK or MTBK and norbornanediamine, those obtained from MIPK or MTBK and MXDA, and those obtained from MIPK or MTBK and polyamidoamine. It is done. Examples of the aldimine include those obtained from pivalaldehyde and NBDA, 1,3BAC or MXDA, and those obtained from isobutyraldehyde and NBDA, 1,3BAC or MXDA.

  Among these ketimines, those obtained from MIPK, MIBK or MTBK and norbornanediamine and those obtained from MIPK or MTBK and 1,3-bisaminomethylcyclohexane are preferred because of their excellent curability.

  Ketimine, which is a reaction product of a polyamine and a carbonyl compound, is not particularly limited for its production. For example, it can be obtained by heating a carbonyl compound and a polyamine in the absence of a solvent or in the presence of a solvent such as benzene, toluene, xylene, refluxing, and reacting while removing azeotropically removed water.

As an amino alkoxysilane which is a raw material of a silicon containing ketimine, the compound represented by following formula (5) is mentioned, for example.

In formula (5), R ⁵ represents an alkyl group having 1 to 6 carbon atoms, an alkoxyl group having 1 to 6 carbon atoms, or a monovalent siloxane derivative. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, and a propyl group. As a C1-C6 alkoxyl group, a methoxy group, an ethoxy group, and a propoxy group are mentioned, for example. Examples of monovalent siloxane derivatives include silyloxy groups. Of these, a methoxy group and an ethoxy group are preferable.

R ⁶ represents a divalent hydrocarbon group which may contain a nitrogen atom. Examples of the divalent hydrocarbon group that does not contain a nitrogen atom include a methylene group, an ethylene group, and a propylene group. Examples of the divalent hydrocarbon group containing a nitrogen atom include a group having an imino group (NH) in a hydrocarbon group exemplified by a divalent hydrocarbon group not containing a nitrogen atom. Among these, R ⁶ is preferably a methylene group, a propylene group, or —C ₂ H ₄ NHC ₃ H ₆ —.

R ⁷ represents an alkoxyl group. As an alkoxy group, a C1-C6 alkoxyl group is mentioned, for example. Specific examples include a methoxy group and an ethoxy group.
m represents any one of 0, 1, 2, and 3.

  Examples of the aminoalkoxysilane represented by the formula (5) include compounds represented by the following formulas (6) to (13). Among these, the compounds represented by the formulas (6) to (9) are preferable.

Examples of the silicon-containing ketimine that is a reaction product of an aminoalkoxysilane and a carbonyl compound include a compound represented by the following formula (14) and a polycondensate having a structure represented by the following formula (15) as a main chain skeleton. Is mentioned.

In the formula (14), R ¹ to R ⁴ are the same as R ¹ to R ⁴ in the formula (4), R ⁵ to R ^7, m is R ⁵ to R ⁷ in formula (5), It is synonymous with m.

Wherein (15), R ¹ to R ⁶ in general formula (14) in the same meaning as R ¹ to R ^6, n represents an integer of 1 or more, preferably from 1 to 50 integer.

  The main chain terminal of the polycondensate represented by the formula (15) includes, for example, a hydrogen atom, a methyl group, an ethyl group, an alkyl group having 1 to 6 carbon atoms such as a propyl group; a methoxy group, an ethoxy group, a propoxy group An alkoxyl group having 1 to 6 carbon atoms such as a group; a monovalent siloxane derivative such as a silyloxy group can be bonded.

  The silicon-containing ketimine is not particularly limited for its production. For example, it can be obtained by dehydrating aminoalkoxysilane and carbonyl compound at room temperature or by heating and stirring. The reaction temperature is preferably 20 to 150 ° C, more preferably 50 to 110 ° C. The reaction time is preferably 2 to 24 hours, more preferably 2 to 5 hours.

  Among these ketimines, those obtained from MIPK and norbornanediamine and those obtained from MIBK and norbornanediamine from the viewpoint of reactivity with urethane prepolymer and epoxy resin, adhesion, storage stability and water resistance. preferable.

  Ketimines can be used alone or in combination of two or more.

The amount of ketimine is such that the molar ratio of the amino group (NH ₂ ) in the curing agent after hydrolysis to the isocyanate group of the urethane prepolymer B and the epoxy group of the epoxy resin [NH ₂ / (NCO and epoxy group)] It is preferably 0.8 to 1.2, and more preferably 0.9 to 1.1. In such a range, the curability and storage stability are excellent.

  An additive will not be restrict | limited especially if the urethane prepolymer B, an epoxy resin, and ketimine are mixed beforehand about the preparation. For example, it can be prepared by thoroughly drying urethane prepolymer B, epoxy resin and ketimine, and uniformly mixing them in the above-mentioned quantitative ratio in a nitrogen gas atmosphere. The obtained additive is preferably stored in a container that is sealed so that moisture does not enter and is replaced with nitrogen gas.

  The amount of the additive is 1 to 50 parts by mass with respect to 100 parts by mass of the urethane prepolymer A. In such a range, the adhesiveness is excellent. Furthermore, from a viewpoint that it is excellent in hardened | cured material physical property, it is more preferable that it is 1-30 mass parts, and it is further more preferable that it is 5-15 mass parts.

  The room temperature curable polyurethane resin composition of the present invention can have a compounding agent as long as it does not impair the object of the present invention, in addition to the composition containing urethane prepolymer A and the additive. The compounding agent is the same as the above compounding agent.

  The room temperature curable polyurethane resin composition of the present invention is not particularly limited with respect to its usage. For example, the composition containing the one-pack type urethane prepolymer A and the additive can be mixed and used in the above-mentioned quantitative ratio.

  When the composition containing the urethane prepolymer A is a two-pack type, for example, the first liquid containing the urethane prepolymer A, the second liquid containing the curing agent, and the additive are simultaneously added and used. be able to. Further, for example, an additive can be added to and mixed with the second liquid containing the curing agent, and this can be used by mixing with the first liquid containing the urethane prepolymer A. In such a case, the additive can also be added to the first liquid.

Examples of uses of the room temperature curable polyurethane resin composition of the present invention include sealing materials, adhesives, coating materials, primers, paints, and waterproofing materials.
Examples of the adherend include mortar, concrete, and fibers such as polyester. A construction method in particular is not restrict | limited, For example, it can construct using a brush, a trowel, a roller, and a gun (coating apparatus).
The cured product obtained from the room temperature curable polyurethane resin composition of the present invention is excellent in initial adhesiveness, hot water resistant adhesiveness, and heat resistant adhesiveness.

  The room temperature curable polyurethane resin composition of the present invention has an additive for the purpose of imparting adhesiveness. The additive includes an epoxy resin, and an epoxy group of the epoxy resin and an amine formed by hydrolysis of ketimine can react to form a hydroxy group. The hydroxy group contributes to adhesion with the adherend and can have excellent adhesion.

  EXAMPLES Next, although an Example demonstrates this invention concretely, this invention is not limited to these Examples.

1. Preparation of Urethane Prepolymer 1 333 parts by mass of polyoxypropylene triol having a number average molecular weight of 4000 (Excenol 4030, manufactured by Asahi Glass Co., Ltd.), 491 parts by mass of polyoxypropylene diol having a number average molecular weight of 2000 (Exenol 2020, manufactured by Asahi Glass Co., Ltd.), As a plasticizer, 50 parts by mass of diisononyl phthalate (DINP, manufactured by Shin Nippon Rika Co., Ltd.) was mixed and dehydrated under reduced pressure at 110 ° C. for 8 hours. Thereafter, 126 parts by mass of the tolylene diisocyanate (mixing ratio of 2,4- and 2,6-tolylene diisocyanate is 80/20, manufactured by Mitsui Takeda Chemical Co., Cosmonate T-80) (of polyol and polyisocyanate). NCO / OH was 1.95 in terms of molar ratio) and reacted at 80 ° C. for 24 hours to prepare urethane urea polymer 1 (NCO group content 2.90 mass%).

2. Additive (1) Preparation of Urethane Prepolymer 2 Polycarbonate diol (Braxel CD220, manufactured by Daicel Chemical Industries, Ltd., weight average molecular weight 2000) 100 g and TMXDI (manufactured by Nippon Cytec Industries, Inc.) with an NCO / OH molar ratio of 2.0 The mixture was mixed at 24.4 g and reacted in the presence of a tin catalyst while stirring at 80 ° C. for 8 hours in a nitrogen stream. After completion of the reaction, 290.3 g of ethyl acetate was added to obtain the desired urethane urea polymer 2 (NCO group content 0.88% by mass).

(2) Preparation of ketimine 100 g of norbornanediamine (NBDA, manufactured by Mitsui Chemicals) and 200 g of methyl isopropyl ketone (MIPK) are placed in a flask together with 200 g of toluene, and reacted for 20 hours while removing generated water by azeotropic distillation. Got ketimine.

(3) Preparation of Additive 1 150.0 g of urethane prepolymer 2 prepared as described above and urethane prepolymer 3 [reaction product of N, 1,1-trimethylolpropane (TMP) and TMXDI (NCO / 34.0 g of Seicen 3174, OH molar ratio = 2.0) manufactured by Nippon Cytec Industries, Ltd., and 30.0 g of bis A type epoxy resin (EP4100, manufactured by Asahi Denka Kogyo Co., Ltd.) as an epoxy resin (The solid content contained in the urethane prepolymer 2 and the urethane prepolymer 3 is 70.0 g). Furthermore, 28.0 g of ketimine prepared as described above (with respect to the total of the isocyanate groups of the urethane prepolymer 2 and the urethane prepolymer 3 and the epoxy group of the epoxy resin, the generated amine was 1.0 by molar ratio). Additive 1) was added and mixed uniformly at room temperature under a nitrogen atmosphere to prepare Additive 1.

(4) Preparation of Additive 2 The amount of urethane prepolymer 2 was 107.3 g, and the amount of urethane prepolymer 3 was 33.8 g (the solid content contained in urethane prepolymer 2 and urethane prepolymer 3 was 50.0 g). And additive 2 was prepared in the same manner as additive 1, except that the amount of epoxy resin was 50.0 g and the amount of ketimine was 34.3 g.

(4) Preparation of additive 3 The amount of urethane prepolymer 2 is 64.3 g, and the amount of urethane prepolymer 3 is 14.5 g (the solid content contained in urethane prepolymer 2 and urethane prepolymer 3 is 30.0 g). And additive 3 was prepared in the same manner as additive 1, except that the amount of epoxy resin was 70.0 g and the amount of ketimine was 33.8 g.

(5) Preparation of Additive 4 The amount of urethane prepolymer 2 is 107.3 g, the amount of urethane prepolymer 3 is 33.8 g, no epoxy resin is used, and the amount of ketimine is 15.2 g (urethane prepolymer). Additive 4 was prepared in the same manner as Additive 1 except that the amount of amine produced was 1.0 in terms of molar ratio with respect to 2 isocyanate groups.

(6) Preparation of Additive 5 Urethane prepolymer 2 and urethane prepolymer 3 were not used, the amount of epoxy resin was 100 g, and the amount of ketimine was 38.2 g (the amine produced with respect to the epoxy group of the epoxy resin). Additive 5 was prepared in the same manner as Additive 1 except that the molar ratio was 1.0).

3. Room temperature curable polyurethane resin compositions For Examples 1 to 7 and Comparative Examples 1 to 3, first, the components of the curing agent shown in Table 1 were prepared in the amounts shown in Table 1 (units are parts by mass). A curing agent mixture was obtained. Next, the urethane prepolymer 1 (first liquid) shown in Table 1, the curing agent mixture (second liquid), and the adhesion-imparting agent in the amounts shown in Table 1 (unit: parts by mass) are 23 ° C. And 55% RH, and each room temperature curable polyurethane resin composition was prepared.
For Example 8, first, the urethane prepolymer 1 shown in Table 1 and the curing agent were mixed in the amounts shown in Table 1 (units are parts by mass) to obtain a one-component polyurethane resin composition. Next, the adhesiveness-imparting agent shown in Table 1 was mixed with the one-component polyurethane resin composition in the amount shown in Table 1 (unit: parts by mass) under the conditions of 23 ° C. and 55% RH. A curable polyurethane resin composition was prepared.

4). Adhesive evaluation The peeling force was evaluated as follows using the obtained room temperature curable polyurethane resin composition. The results are shown in Table 1.

(1) Preparation of test body As a to-be-adhered body, one mortar board 25 cm long and 25 mm wide and one sheet of polyester nonwoven fabric of the same size were used.
The obtained room temperature curable polyurethane resin composition was applied to a mortar plate at 23 ° C. and 55% RH so as to be 0.2 kg / m ^2, and a test piece 1 was obtained by laminating a sheet thereto. .
(2) Measurement of peeling force The specimen 1 was cured and cured for 7 days under the conditions of 23 ° C and 55% RH.
Next, the 180 ° peel tensile test was performed on the cured specimen under the condition of a tensile speed of 50 mm / min, the peeling force was measured, the average value was obtained, and this value was taken as the initial peeling force.

  The specimen 1 was cured for 7 days under conditions of 23 ° C. and 55% RH, and then placed in warm water at 50 ° C. for 7 days. Seven days later, the specimen was pulled up from the water, and the peel strength of the specimen was measured in the same manner as described above to measure the peel force, and the average value was obtained. This value was taken as the hot water peel strength.

Specimen 1 was cured by curing for 7 days under conditions of 23 ° C. and 55% RH, and then placed under conditions of 80 ° C. for 7 days. Seven days later, the test piece was subjected to a 180 ° peel tensile test in the same manner as described above, the peeling force was measured, the average value was obtained, and this value was taken as the heat-resistant peeling force.

The details of each component in Table 1 are as follows.
Urethane prepolymer 1: Urethane prepolymer 1 prepared as described above
Polyol compound 1: Polypropylene triol with a number average molecular weight of 5000, trade name: Exenol 5030, manufactured by Asahi Glass Co., Ltd. Polyol compound 2: Polypropylene diol with a number average molecular weight of 2000, trade name: Exenol 2020, manufactured by Asahi Glass Co., Ltd .: Amine compound: 4, 4'-methylenebis (2-chloroaniline) (Cuamine MT, manufactured by Ihara Chemical Co., Ltd.)
Filler: Calcium carbonate, trade name: Calfine 200, manufactured by Maruo Calcium Co., Ltd. Plasticizer: DINA (Diisononyl adipate), manufactured by Jay Plus Co., Ltd. Curing catalyst: Lead octylate, manufactured by Active Materials Chemical Co., Ltd.

As is apparent from the results shown in Table 1, Examples 3 to 8 have a higher peeling force than Comparative Examples 1 to 3, and the cured products that can be obtained from the room temperature curable polyurethane resin composition of the present invention are: It can be seen that the initial adhesiveness, hot water resistant adhesiveness and heat resistant adhesiveness are excellent.
Since Comparative Example 1 contains a TDI-derived urethane prepolymer, the curing rate is high, and further, no adhesiveness-imparting agent is contained, and therefore the adhesiveness is low. Since Comparative Example 2 includes a urethane prepolymer derived from TMXDI, the curing rate is slower than that of Comparative Example 1, but it does not contain an epoxy resin capable of imparting adhesiveness, so that the adhesiveness is low. Since Comparative Example 3 does not include the urethane prepolymer 2, the curing rate is considered to be the same as that of Comparative Example 1, but has an adhesive property compared to Comparative Examples 1 and 2 because it contains an epoxy resin.
Comparing Comparative Example 3 with Examples 3 and 8, Example 3 and Example 8 containing additive 2 had an initial peeling force higher than that of Comparative Example 3, and both hot water resistance and heat resistance were both high and adhesive. Excellent. The inventors infer that this is because Examples 3 and 8 contain an additive to suppress the moisture curing reaction of the urethane prepolymer and promote the curing reaction with ketimine.
From the results of Examples 3 to 5, it can be seen that as the amount of the additive increases, the peeling force increases and the adhesiveness is excellent.
When Examples 1 and 2 are compared with Comparative Example 3, Examples 1 and 2 show a peeling force substantially equal or equal to or higher than that of Comparative Example 3, although the content of the adhesion-imparting agent is lower. It can be seen that the room temperature curable polyurethane resin composition is excellent in adhesiveness by containing.

Claims (3)

A room temperature curable polyurethane resin composition comprising a composition containing a urethane prepolymer A, and a premixed urethane prepolymer B, an epoxy resin, and an additive containing a ketimine,
The amount of the additive is 1 to 50 parts by mass with respect to 100 parts by mass of the urethane prepolymer A,
The isocyanate group of the urethane prepolymer A is bonded to an aromatic ring,
The urethane prepolymer B can be obtained by reacting a polyisocyanate compound having a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms and a polycarbonate polyol, and is cured at room temperature. Composition.   The room temperature curable polyurethane resin composition according to claim 1, wherein the ketimine has a structure in which a branched carbon atom or a ring member carbon atom is bonded to the α-position of at least one of a carbon atom and a nitrogen atom of a ketimine bond. . Room temperature curable polyurethane resin composition obtained by adding an additive containing urethane prepolymer B, epoxy resin and ketimine mixed in advance to a composition containing urethane prepolymer A to obtain a room temperature curable polyurethane resin composition A method for manufacturing a product,
The amount of the additive, with respect to the urethane prepolymer A100 parts by mass Ri 1 to 50 parts by mass der,
The isocyanate group of the urethane prepolymer A is bonded to an aromatic ring,
The urethane prepolymer B can be obtained by reacting a polyisocyanate compound having a structure in which all isocyanate groups in the molecule are bonded to tertiary carbon atoms and a polycarbonate polyol, and is cured at room temperature. A method for producing the composition.