JP2024001044A - Urethane prepolymer, polyurethane and sealing material using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyurethane that has low tackiness, high strength and high transparency.

SOLUTION: Provided is a NCO-terminated liquid urethane prepolymer, the urethane prepolymer containing a structural unit represented by formula (1) and having a number average molecular weight of 200 or more and 3,000 or less, in which the degree of unsaturation is 0.020 meq/g or less, and the terminal is a NCO group. In formula (1), Q represents a polymer component containing a halogenated polyether structural unit, m represents an integer of 2 to 8, and R¹ represents an active hydrogen-containing compound residue.

SELECTED DRAWING: None

COPYRIGHT: (C)2024,JPO&INPIT

Description

The present disclosure relates to a urethane prepolymer, a polyurethane using the same, and a sealing material.

Cured polyurethane compositions used as sealants, paints, coating materials, pressure-sensitive adhesives, and adhesives include one-component compositions that are cured by moisture in the air, and two-component compositions that are cured by mixing polyols, polyamines, etc. with a curing agent. Examples include a mold, a 1.5-liquid type containing a latent curing agent, and the like. As the main component for forming such polyurethane, a curable resin composition containing an NCO-terminated urethane prepolymer made by reacting isocyanate with a polyol, fillers, and additives is widely used.As the polyol, polyester polyol and polyalkylene oxide polyols.

Since polyurethane obtained using polyester polyol contains an ester group, there is a problem that it has poor water resistance due to hydrolysis.

Polyalkylene oxide, which is produced industrially by addition polymerization of alkylene oxide such as propylene oxide using an alkali metal such as potassium hydroxide as a catalyst, contains many impurities and therefore has poor curability and lacks sufficient resin strength. The problem was that it was not possible to obtain

Halogen-containing polyether polyols are known as raw materials for polyurethane adhesives that have excellent shear strength, moisture resistance, and water resistance (see, for example, Patent Document 1). Such a halogen-containing polyether polyol can be synthesized by ring-opening polymerization of a halogen-containing alkylene oxide using an acid catalyst such as a boron trifluoride compound.

Japanese Unexamined Patent Publication No. 202573/1999

However, the polyol used as a raw material for the adhesive composition according to Patent Document 1 contains many impurities and unsaturated components because epichlorohydrin is ring-opened using a Lewis acid catalyst. As a result, the obtained cured product has many defective parts and the crosslinking density decreases, which causes problems such as insufficient resin strength unless a large amount of filler is included and stickiness on the resin surface.

Each aspect of the present invention is [1] to [6] shown below.
[1] NCO-terminated liquid urethane prepolymer,
The urethane prepolymer is
Contains a structural unit represented by formula (1) and having a number average molecular weight of 200 or more and 3,000 or less, and
The degree of unsaturation is 0.020 meq/g or less,
Liquid urethane prepolymer with NCO group at the end:

In formula (1),
Q represents a polymer component containing a structural unit represented by formula [I],
m represents an integer from 2 to 8,
R ¹ represents an active hydrogen-containing compound residue;

In formula [I], X represents a halogen atom.
[2]
The liquid urethane prepolymer according to item 1, characterized in that the degree of unsaturation is 0.016 meq/g or less.
[3]
Contains the urethane prepolymer according to any one of [1] and [2], and one or more of fillers, other polyols, urethanization catalysts, foam stabilizers, antioxidants, and plasticizers. , a liquid urethane prepolymer composition.
[4]
The liquid urethane prepolymer according to any one of [1] to [2] or the liquid urethane prepolymer composition according to [3] reacts with water in the air or a curing agent (active hydrogen-containing compound). Polyurethane that hardens.
[5]
A composition for a sealant, comprising the urethane prepolymer according to any one of [1] to [2] or the urethane prepolymer composition according to [3].
[6]
A sealing material obtained by curing the sealing material composition according to [5] by reaction with water in the air or a curing agent (active hydrogen-containing compound).

According to one aspect of the present invention, a polyurethane with low tackiness, high strength, and high transparency can be provided, and can be suitably used for applications such as sealants.

Hereinafter, exemplary embodiments for carrying out the present invention will be described in detail.
<Urethane prepolymer>
The urethane prepolymer according to one embodiment of the present invention is
It can be obtained by reacting a halogen-containing polyether polyol with an isocyanate compound.
<<Halogen-containing polyether polyol>>
The halogen-containing polyether polyol is
It is shown by formula (2),
Average molecular weight is 200 or more and 3,000 or less:

In formula (2),
Q represents a polymer component containing a structural unit represented by formula [I],
m represents an integer from 2 to 8,
R ¹ represents an active hydrogen-containing compound residue;

In formula [I], X represents a halogen atom.

In formula [I], the halogen atom represented by X is not particularly limited, and examples thereof include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom. Among these, fluorine atom, chlorine atom, and bromine atom are preferred from the viewpoint of ease of handling, and fluorine atom or chlorine atom is more preferred.

In formulas (1) and (2), the active hydrogen-containing compound residue represented by R ¹ is not particularly limited, but includes, for example, hydroxy residues, amine residues, carboxylic acid residues, and thiol residues. Examples include residues.

In addition, active hydrogen-containing compounds containing such active hydrogen-containing compound residues are not particularly limited, but include, for example, hydroxy compounds, amine compounds, carboxylic acid compounds, thiol compounds, and polyether polyols having hydroxyl groups. etc.

Examples of the hydroxy compound include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, and 2,3-butanediol. , 1,6-hexanediol, 1,9-nonanediol, 2,5-hexanediol, 1,3-cyclohexanediol, 2-methylpentane-2,4-diol, 2,5-dimethyl-2,5- Examples include hexanediol, glycerin, trimethylolpropane, hexanetriol, pentaerythritol, diglycerin, sorbitol, sucrose, glucose, 2-naphthol, and bisphenol.

Examples of the amine compound include ethylene diamine, 1,3-propylene diamine, 1,4-butylene diamine, and 1,2-butylene diamine.

Examples of the carboxylic acid compound include phthalic acid and adipic acid.

Examples of the thiol compound include ethanedithiol, butanedithiol, and the like.

Examples of the polyether polyol having a hydroxyl group include polyether polyols having a molecular weight of 200 or more and 1000 or less.

Among these active hydrogen-containing compounds, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,9-nonanediol, 2,5-hexanediol, 1,6-hexanediol, 2-methylpentane-2,4-diol, ethylenediamine, polyether polyols with a molecular weight of 200 to 1,000 are preferred, tripropylene glycol, 2,5-hexane Particularly preferred are diols, 1,9-nonanediol, and polyether polyols having a molecular weight of 200 or more and 1,000 or less.

The number average molecular weight of the halogen-containing polyether polyol is 200 or more and 3,000 or less, and the number average molecular weight is preferably 200 or more and 2,000 or less, and 500 or more, since it has excellent handling properties and polyurethane production efficiency. It is particularly preferable that the number is 2,000 or less.

The degree of unsaturation of the halogen-containing polyether polyol is preferably 0.02 meq/g or less, particularly preferably 0.01 meq/g or less, in order to improve the curability when made into polyurethane.

The ratio (Mw/Mn) of the mass average molecular weight Mw to the number average molecular weight Mn of the halogen-containing polyether polyol is preferably 2.00 or less, particularly preferably 1. 50 or less. However, the number average molecular weight determined by gel permeation chromatography measurement using polystyrene as a standard substance is Mn, and the mass average molecular weight is Mw.

The degree of primaryization of the terminal hydroxyl groups in the halogen-containing polyether polyol is not particularly limited, but it is because the variation in reactivity is small, the reaction is uniform, and the resulting polyurethane tends to have a uniform molecular weight distribution and composition. , is preferably less than 10%, more preferably 8% or less, particularly preferably 5% or less.
<<Production method of halogen-containing polyether polyol>>
There are no particular restrictions on the method for producing the halogen-containing polyether polyol, and it can be produced by conventionally known production methods.

For example, (A) a method of adding a halogen-containing alkylene oxide to a bifunctional or more active hydrogen compound using a Lewis acid catalyst or a multimetal cyanide complex catalyst to a predetermined molecular weight; (B) a method of adding a halogen-containing alkylene oxide to a bifunctional or more active hydrogen compound; and a method of ring-opening polymerization of a halogen-containing alkylene oxide in the presence of an onium salt catalyst such as a phosphazenium salt, an ammonium salt, or a phosphonium salt, and a Lewis acid catalyst.

Examples of Lewis acid catalysts include aluminum compounds, zinc compounds, and boron compounds.

Examples of aluminum compounds include trimethylaluminum, triethylaluminum, triisobutylaluminum, trinormalhexylaluminum, triethoxyaluminum, triisopropoxyaluminum, triisobutoxyaluminum, triphenylaluminum, diphenylmonoisobutylaluminum, monophenyldiisobutylaluminum, and the like. organic aluminum; aluminoxanes such as methylaluminoxane, isobutylaluminoxane, and methyl-isobutylaluminoxane; and inorganic aluminum such as aluminum chloride, aluminum hydroxide, and aluminum oxide.

Examples of the zinc compound include organic zinc such as dimethylzinc, diethylzinc, and diphenylzinc; and inorganic zinc such as zinc chloride and zinc oxide.

Examples of the boron compound include triethylborane, trimethoxyborane, triethoxyborane, triisopropoxyborane, triphenylborane, tris(pentafluorophenyl)borane, and trifluoroborane.

Among these, organoaluminum, aluminoxane, and organozinc are preferred, and organoaluminum is particularly preferred, since they provide a catalyst for producing a halogen-containing polyether polyol with excellent catalytic performance.

The halogen-containing alkylene oxide described in (B) is easy to obtain because it is easy to obtain a halogen-containing polyalkylene oxide with a low degree of unsaturation and a narrow molecular weight distribution, and the handling property when making it into a prepolymer is easily improved and the resulting prepolymer has excellent curability. It is preferable to produce a halogen-containing polyether polyol by ring-opening polymerization of an oxide.

The structure of the phosphazenium salt used in the production of the halogen-containing polyether polyol is not particularly limited.

The phosphazenium salt is, for example, a phosphazenium salt represented by formula (3):

In formula (3),
R ² and R ³ are each independently,
hydrogen atom,
a hydrocarbon group having 1 to 20 carbon atoms,
A ring structure in which R ² and R ³ are bonded to each other,
Represents a ring structure in which R ² or R ³ are bonded to each other;
Z ⁻ represents a hydroxy anion, an alkoxy anion having 1 to 4 carbon atoms, a carboxy anion, an alkyl carboxy anion having 2 to 5 carbon atoms, a chlorine anion, a bromine anion, an iodine anion, or a hydrogen carbonate anion;
Y represents a carbon atom or a phosphorus atom;
a is
2 when Y is a carbon atom,
When Y is a phosphorus atom, it is 3.

In formula (3), the hydrocarbon group having 1 to 20 carbon atoms represented by R ² and R ³ is not particularly limited, but includes, for example, a methyl group, an ethyl group, a vinyl group, and a n-propyl group. group, isopropyl group, cyclopropyl group, allyl group, n-butyl group, isobutyl group, t-butyl group, cyclobutyl group, n-pentyl group, neopentyl group, cyclopentyl group, n-hexyl group, cyclohexyl group, phenyl group, Heptyl group, cycloheptyl group, octyl group, cyclooctyl group, nonyl group, cyclononyl group, decyl group, cyclodecyl group, undecyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, hexadecyl group, heptadecyl group, octadecyl group , nonadecyl group, etc.

Examples of the case where R ² and R ³ are bonded to each other to form a ring structure include a pyrrolidinyl group, a pyrrolyl group, a piperidinyl group, an indolyl group, an isoindolyl group, and the like.

The ring structure in which R ² or R ³ are bonded to each other is not particularly limited, but for example, two R ² or two R ³ are each independently a methylene group, an ethylene group, a propylene group. , a ring structure in which one alkylene group and the other alkylene group are bonded to each other as one group selected from alkylene groups such as butylene group.

Among these, R ² and R ³ are preferably a methyl group, an ethyl group, or an isopropyl group because they provide an alkylene oxide polymerization catalyst with particularly excellent catalytic activity and raw materials are easily available.

Further, Z ⁻ in formula (3) is a hydroxy anion, an alkoxy anion having 1 to 4 carbon atoms, a carboxy anion, an alkylcarboxy anion having 2 to 5 carbon atoms, or a hydrogen carbonate anion.

The alkoxy anion having 1 to 4 carbon atoms is not particularly limited, but includes, for example, methoxy anion, ethoxy anion, n-propoxy anion, isopropoxy anion, n-butoxy anion, isobutoxy anion, and t-butoxy anion. etc.

Examples of the alkylcarboxy anion having 2 to 5 carbon atoms include, but are not limited to, acetoxy anion, ethyl carboxy anion, n-propyl carboxy anion, isopropyl carboxy anion, n-butyl carboxy anion, isobutyl carboxy anion, Examples include t-butyl carboxy anion.

Among these, Z ^- is particularly preferably a hydroxy anion or a hydrogen carbonate anion, since they provide a halogen-containing alkylene oxide polymerization catalyst with excellent catalytic activity.

The phosphazenium salt represented by formula (3) is not particularly limited, but specifically, tetrakis(1,1,3,3-tetramethylguanidino)phosphonium hydroxide, tetrakis(1,1, 3,3-tetraethylguanidino)phosphonium hydroxide, tetrakis(1,1,3,3-tetra(n-propyl)guanidino)phosphonium hydroxide, tetrakis(1,1,3,3-tetraisopropylguanidino)phosphonium hydroxide , tetrakis(1,1,3,3-tetra(n-butyl)guanidino)phosphonium hydroxide, tetrakis(1,1,3,3-tetraphenylguanidino)phosphonium hydroxide, tetrakis(1,1,3,3 -tetrabenzylguanidino)phosphonium hydroxide, tetrakis(1,3-dimethylimidazolidine-2-imino)phosphonium hydroxide, tetrakis(1,3-diethylimidazolidine-2-imino)phosphonium hydroxide, tetrakis(1,1 , 3,3-tetramethylguanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3,3-tetraethylguanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3,3-tetra(n-propyl)guanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3,3-tetraisopropylguanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3,3-tetra(n-butyl)guanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3, 3-tetraphenylguanidino)phosphonium hydrogen carbonate, tetrakis(1,1,3,3-tetrabenzylguanidino)phosphonium hydrogen carbonate, tetrakis(1,3-dimethylimidazolidine-2-imino)phosphonium hydrogen carbonate, tetrakis(1, Examples include 3-diethylimidazolidine-2-imino)phosphonium hydrogen carbonate.

Also, tetrakis[tris(dimethylamino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris(diethylamino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris(di-n-propylamino)phosphoranylideneamino]phosphonium hydroxy tetrakis[tris( diisopropylamino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris(di-n-butylamino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris(diphenylamino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris (1,3-dimethylimidazolidine-2-imino)phosphoranylideneamino]phosphonium hydroxide, tetrakis[tris(dimethylamino)phosphoranylideneamino]phosphonium hydrogen carbonate, tetrakis[tris(diethylamino)phosphoranylideneamino]phosphonium Hydrogen carbonate, Tetrakis[tris(di-n-propylamino)phosphoranylideneamino]phosphonium hydrogen carbonate, Tetrakis[tris(diisopropylamino)phosphoranylideneamino]phosphonium hydrogen carbonate, Tetrakis[tris(di-n-butylamino)phosphoranylidene Examples include tetrakis[tris(diphenylamino)phosphoranylideneamino]phosphonium hydrogen carbonate, tetrakis[tris(1,3-dimethylimidazolidine-2-imino)phosphoranylideneamino]phosphonium hydrogen carbonate, etc. can do.

Among these, tetrakis(1,1,3,3-tetramethylguanidinophosphonium hydroxide, tetrakis(1,1,3,3-tetramethyl Particularly preferred are guanidino)phosphonium hydrogen carbonate and tetrakis[tris(dimethylamino)phosphoranylideneamino]phosphonium hydroxide.

The structure of ammonium salt or phosphonium salt is represented by formula (4):

In formula (4),
D represents a nitrogen atom or a phosphorus atom;
R ⁴ , R ⁵ , R ⁶ and R ⁷ are each independently,
an alkyl group, aryl group, alkoxy group, or dialkylamino group having 1 to 20 carbon atoms;
a halogen atom, or
Represents a hydrogen atom;
E ^- represents a counter ion consisting of an inorganic or organic group;
Two to four of R ⁴ to R ⁷ may be combined to form a cyclic structure, and the cyclic structure may contain a heteroatom.

In formula (4), the alkyl group and aryl group having 1 to 20 carbon atoms represented by R ⁴ , R ⁵ , R ⁶ and R ⁷ are not particularly limited, but include, for example, methyl group and ethyl group. group, vinyl group, normal propyl group, isopropyl group, cyclopropyl group, allyl group, normal butyl group, isobutyl group, t-butyl group, cyclobutyl group, normal pentyl group, neopentyl group, cyclopentyl group, normal hexyl group, cyclohexyl group , phenyl group, heptyl group, cycloheptyl group, benzyl group, tolyl group, octyl group, cyclooctyl group, xylyl group and the like.

In formula (4), the alkoxy group having 1 to 20 carbon atoms represented by R ⁴ , R ⁵ , R ⁶ and R ⁷ includes methoxy group, ethoxy group, vinyloxy group, normal propoxy group, isopropoxy group, cyclo Propoxy group, allyloxy group, normal butoxy group, isobutoxy group, t-butoxy group, cyclobutoxy group, normal pentyloxy group, neopentyloxy group, cyclopentyloxy group, normal hexyloxy group, cyclohexyloxy group, phenoxy group, heptyloxy group Examples include a cycloheptyloxy group, an octyloxy group, a benzyloxy group, a tolyloxy group, a cyclooctyloxy group, and a xylyloxy group.

In formula (4), the dialkylamino group having 1 to 20 carbon atoms represented by R ⁴ , R ⁵ , R ⁶ and R ⁷ includes a dimethylamino group, a diethylamino group, a pyrrolidino group, a piperidino group, and a dinormalpropylamino group. group, diisopropylamino group, dicyclopropylamino group, etc.

Examples of the halogen atom include, but are not limited to, a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

Since the catalyst for producing halogen-containing polyether polyol has excellent catalytic activity, R ⁴ , R ⁵ , R ⁶ and R ⁷ each independently represent an alkyl group having 1 to 10 carbon atoms which may contain a hetero atom or An aryl group is preferable, and a methyl group, ethyl group, normal butyl group, normal octyl group or phenyl group is particularly preferable.

Two to four of R ⁴ to R ⁷ may be combined to form a cyclic structure, and preferably two or three are combined to form a cyclic structure. The cyclic structure may contain heteroatoms.

Examples of ammonium salt structures in which two or three of R ⁴ to R ⁷ are bonded to form a cyclic structure include pyridinium salts and imidazolium salts, which serve as catalysts for producing halogen-containing polyether polyols with excellent catalytic activity. Therefore, imidazolium salts are preferred.

In formula (4), the inorganic or organic group represented by E ^- is not particularly limited, but specifically includes a halogen atom, a hydroxyl group, an alkoxyl group, an amino group, a carboxyl group, and a sulfonic acid group. Examples include a group, a borohydride group, and a hexafluorophosphate group. E ^- is preferably a bromine atom, a chlorine atom, an iodine atom, or a hexafluorophosphoric acid group, since this provides a catalyst for producing a halogen-containing polyether polyol with excellent catalytic activity.

The ammonium salt or phosphonium salt represented by formula (4) is not particularly limited, but specific examples include tetramethylammonium bromide, tetraethylammonium bromide, tetranpropylammonium bromide, and tetranbutylammonium bromide. , tetranormal pentylammonium bromide, tetranormalhexylammonium bromide, tetranormalheptylammonium bromide, tetranormaloctylammonium bromide, tetramethylammonium chloride, tetraethylammonium chloride, tetranormalpropylammonium chloride, tetranormalbutylammonium chloride, tetranormalpentylammonium Chloride, tetranormalhexylammonium chloride, tetranormalheptylammonium chloride, tetranormaloctylammonium chloride, 1-butyl-3-methylimidazolium chloride, 1-butyl-2,3-dimethylimidazolium chloride, 1-ethyl-3- Methylimidazolium chloride, tetramethylphosphonium bromide, tetraethylphosphonium bromide, tetranormalpropylphosphonium bromide, tetranormalbutylphosphonium bromide, tetranormalpentylphosphonium bromide, tetranormalhexylphosphonium bromide, tetranormalheptylphosphonium bromide, tetranormaloctylphosphonium bromide, Tetramethylphosphonium chloride, Tetraethylphosphonium chloride, Tetranormalpropylphosphonium chloride, Tetranormalbutylphosphonium chloride, Tetranormalpentylphosphonium chloride, Tetranormalhexylphosphonium chloride, Tetranormalheptylphosphonium chloride, Tetranormaloctylphosphonium chloride, Bromotris (dimethylamino) Examples include phosphonium hexafluorophosphate.

Among these, tetra-n-octylammonium chloride, tetra-n-octylammonium bromide, tetra-n-butylammonium chloride, tetra-n-butylammonium bromide, and tetra-n-ethylammonium chloride are used as catalysts for producing halogen-containing polyether polyols with excellent catalytic activity. , tetra-n-ethylammonium bromide, and tetra-n-butylphosphonium bromide are preferably used.

The polymerization temperature when producing a halogen-containing polyether polyol is not particularly limited, but is in the range of 70 to 150°C because the polyalkylene oxide decomposes and the molecular weight distribution is difficult to widen, making it easy to develop catalytic activity. The temperature is preferably in the range of 90 to 110°C, and more preferably in the range of 90 to 110°C.

In the method for producing a halogen-containing polyether polyol, the polymerization reaction is preferably carried out without a solvent, but it can also be carried out in a solvent. Examples of the solvent used include benzene, toluene, xylene, cyclohexane, 1,2-dichloroethane, chlorobenzene, dichlorobenzene, 1,4-dioxane, and 1,2-dimethoxyethane.
<<Isocyanate compound>>
Isocyanate compounds are not particularly limited, and include, for example, aromatic isocyanate compounds, aliphatic isocyanate compounds, alicyclic isocyanate compounds (monocyclic alicyclic isocyanate compounds, bridged cyclic alicyclic isocyanate compounds), and polycyclics thereof. Examples include isocyanate derivatives.

Examples of aromatic isocyanate compounds include tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate, or a mixture thereof) (TDI), phenylene diisocyanate (m- or p-phenylene diisocyanate, or mixtures thereof), 4,4'-diphenyl diisocyanate, diphenylmethane diisocyanate (4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate, or mixtures thereof) (MDI), 4,4'- Toluidine diisocyanate (TODI), 4,4'-diphenyl ether diisocyanate, xylylene diisocyanate (1,3- or 1,4-xylylene diisocyanate, or a mixture thereof) (XDI), tetramethylxylylene diisocyanate (1,3- or 1,4-tetramethylxylylene diisocyanate, or mixtures thereof) (TMXDI), ω,ω'-diisocyanate-1,4-diethylbenzene, naphthalene diisocyanate (1,5-, 1,4- or 1,8- naphthalene diisocyanate (or mixtures thereof) (NDI), triphenylmethane triisocyanate, tris(isocyanate phenyl) thiophosphate, polymethylene polyphenylene polyisocyanate, nitrodiphenyl-4,4'-diisocyanate, 3,3'-dimethyldiphenylmethane- Examples include 4,4'-diisocyanate, 4,4'-diphenylpropane diisocyanate, and 3,3'-dimethoxydiphenyl-4,4'-diisocyanate.

Examples of aliphatic isocyanate compounds include trimethylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate (tetramethylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, diisocyanate), hexamethylene diisocyanate, pentamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, 2,6-diisocyanate methyl capate, lysine diisocyanate, lysine ester triisocyanate, Examples include 1,6,11-undecane triisocyanate, 1,3,6-hexamethylene triisocyanate, trimethylhexamethylene diisocyanate, decamethylene diisocyanate, and the like.

Examples of monocyclic alicyclic isocyanate compounds include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,4-cyclohexane diisocyanate, 1,3-cyclohexane diisocyanate), 3-Isocyanatomethyl-3,5,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI), methylene bis(cyclohexyl isocyanate (4,4'-, 2,4'- or 2,2'-methylene bis(cyclohexyl isocyanate), or (mixture of hydrogenated MDI), methylcyclohexane diisocyanate (methyl-2,4-cyclohexane diisocyanate, methyl-2,6-cyclohexane diisocyanate, bis(isocynatemethyl)cyclohexane (1,3- or 1,4-bis (isocyanatomethyl)cyclohexane, or mixtures thereof) (hydrogenated XDI), dimer acid diisocyanate, transcyclohexane 1,4-diisocyanate, hydrogenated tolylene diisocyanate (hydrogenated TDI), hydrogenated tetramethyl TMXDI), etc.

Examples of the crosslinked alicyclic isocyanate compound include norbornene diisocyanate, methyl norbornane diisocyanate, bicycloheptane triisocyanate, methyl diisocyanate, bicycloheptane, and di(diisocyanatomethyl)tricyclodecane.

Further, as derivatives of these polyisocyanates, for example, multimers (dimers, trimers, pentamers, heptamers, uretidinedione, ureitoneimine, isocyanurate modified products, polycarbodiimides, etc.) of the above-mentioned isocyanate compounds. , urethane modified products (for example, urethane modified products in which a part of the isocyanate group in the above isocyanate compound or polymer is modified or reacted with a monool or polyol), biuret modified products (for example, a reaction between the above isocyanate compound and water) biuret modified products produced by the reaction of the above-mentioned isocyanate compound with a monool or polyol component), allophanate modified products (for example, the allophanate modified products produced by the reaction of the above-mentioned isocyanate compound with a monool or polyol component), urea-modified products (for example, the reaction of the above-mentioned isocyanate compound with a diamine) (eg, urea modified product produced by), oxadiazinetrione (for example, oxadiazinetrione produced by the reaction of the above-mentioned isocyanate compound with carbon dioxide, etc.), and the like.

In addition, the above-mentioned isocyanate compounds or derivatives thereof may be used alone or in combination of two or more.

The amount of the isocyanate compound to be added is not particularly limited as long as the terminal is NCO, but since it is difficult to generate free isocyanate that worsens the working environment such as free TDI and HDI, it is important to consider the total amount of NCO groups in the isocyanate compound and the halogen-containing polyester. The amount added is preferably in a range such that the ratio of the total amount of OH groups in the ether polyol (described as NCO/OH ratio) is 1.2 or more and 3.0 or less, particularly preferably 1.5 or more and 2.5 or less.
<<Liquid urethane prepolymer composition>>
The urethane prepolymer composition according to one embodiment of the present invention includes a filler and one or more of other polyols, urethanization catalysts, foam stabilizers, antioxidants, and plasticizers. The mixing order when using these is not particularly limited and can be selected as appropriate.

Fillers include inorganic fillers and organic fillers.

Inorganic fillers include silica, alumina, zinc oxide, titanium oxide, calcium oxide, magnesium oxide, iron oxide, tin oxide, antimony oxide, ferrites, calcium hydroxide, magnesium hydroxide, aluminum hydroxide, and basic magnesium carbonate. , calcium carbonate, zinc carbonate, barium carbonate, dawsonite, hydrotalcite, calcium sulfate, barium sulfate, calcium silicate, talc, clay, mica, montmorillonite, bentonite, sepiolite, imogolite, sericite, glass fiber, glass beads, silica Examples thereof include aluminum nitride, boron nitride, silicon nitride, carbon black, graphite, carbon fiber, carbon balloon, zinc borate, and various magnetic powders.

Examples of organic fillers include synthetic organic fine particles such as polystyrene, polyacrylonitrile, polymethyl methacrylate, polypropylene, polyethylene, polyvinyl chloride, and polyurethane, wood flour, bamboo flour, sawdust, paper pulp, and wood obtained from paper pulp. Examples include natural organic fine particles such as purified cellulose powder.

The antioxidant is not particularly limited, and includes, for example, compounds effective in suppressing oxidation of polymer chains, such as thioether compounds, phosphorus antioxidants, and hindered phenol compounds.

Other polyols are not particularly limited as long as they do not deviate from the purpose; for example, polyether polyols obtained by ring-opening polymerization of alkylene oxide, polymer polyols obtained by radical polymerization of vinyl monomers in polyether polyols, etc. , polyester polyols obtained by polycondensation of polyhydric alcohols and polycarboxylic acids, polyesteramide polyols obtained by polycondensation of polyhydric alcohols, polycarboxylic acids, and amino alcohols, and ring opening of lactones. Polylactone polyols obtained by polymerization, polycarbonate polyols obtained by polycondensation of polyhydric alcohols and carbonates, acrylic polyols, polybutadiene polyols and their hydrogenated products, polyisoprene polyols and their hydrogenated products, Examples include partially saponified ethylene-vinyl acetate copolymer, natural oil-based polyols such as soybean oil and castor oil, and the like.

As the urethanization catalyst, a known urethanization catalyst can be used. Examples include tertiary amine compounds, organometallic compounds, and the like.

Examples of the tertiary amine compound include, but are not limited to, triethylamine, triethylenediamine, N,N-dimethylbenzylamine, N-methylmorpholine, diazabicycloundecene (also known as DBU), and the like. These can be used alone or in combination of two or more.

Examples of organometallic compounds include, but are not limited to, tin-based compounds and non-tin-based compounds.

Examples of tin-based compounds include, but are not limited to, dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate (also known as DBTDL), dibutyltin diacetate, dibutyltin sulfide, and tributyltin. Sulfide, tributyltin oxide, tributyltin acetate, triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin chloride, tributyltin trichloroacetate, dioctyltin dilaurylate (also known as DOTDL), tin 2-ethylhexanoate, etc. .

Non-tin compounds include, but are not particularly limited to, titanium compounds such as dibutyl titanium dichloride, tetrabutyl titanate, butoxytitanium trichloride, lead oleate, lead 2-ethylhexanoate, lead benzoate, lead naphthenate, etc. lead-based, iron-based such as iron 2-ethylhexanoate, iron acetylacetonate, cobalt-based such as cobalt benzoate, cobalt 2-ethylhexanoate, zinc-based such as zinc naphthenate, zinc 2-ethylhexanoate, etc. Examples include zirconium naphthenate.

Among the above-mentioned urethanation catalysts, dibutyltin dilaurate (also known as DBTDL), dioctyltin dilaurate (also known as DOTDL), tin 2-ethylhexanoate, etc. are preferred from the viewpoint of reactivity and hygiene.

The above catalysts such as tertiary amine compounds and organometallic compounds can be used alone, but two or more types can also be used in combination.

Plasticizers are not particularly limited, and include, for example, phthalic acid esters, non-aromatic dibasic acid esters, aliphatic esters, polyalkylene glycol esters, phosphoric acid esters, trimellitic acid esters, and chlorine. Examples include paraffins, hydrocarbon oils, process oils, polyethers, epoxy plasticizers, polyester plasticizers, and phthalate esters are preferred. Specifically, dibutyl phthalate, diheptyl phthalate, di(2-ethylhexyl) phthalate, dioctyl phthalate, dioctyl adipate, dioctyl sebacate, dibutyl sebacate, isodecyl succinate, tricresyl phosphate, tributyl phosphate, epoxidized soybean oil. , benzyl epoxy stearate, and the like.

The foam stabilizer is not particularly limited, but includes, for example, silicone compounds.
<Polyurethane>
The polyurethane according to one embodiment of the present invention is obtained by curing the above liquid urethane prepolymer or urethane prepolymer composition by reaction with water in the air or a curing agent (active hydrogen-containing compound).

When curing the urethane prepolymer composition, it can be cured with one component using moisture in the air (one-component type), or it can be cured with two components by using a curing agent (active hydrogen-containing compound). Good (2 liquid type).

The one-component type includes a one-component moisture-curing type that is cured by reaction with moisture in the air, and a one-component latent curing agent type (1.5-component type) that is cured by an active hydrogen-containing compound obtained from a latent curing agent. ), and examples of two or more components include a two-component curing type in which a main agent containing the liquid urethane prepolymer of the present invention is mixed with a curing agent and other auxiliary materials to be cured. Any one can be suitably selected depending on the required characteristics.

The active hydrogen-containing compound is not particularly limited as long as it contains one or more compounds having one or more active hydrogen groups. For example, water, polypropylene glycol, polyethylene propylene glycol, ethylene glycol (EG), diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol (1,4-BD), 1, Diols such as 6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, and 1,4-dihydroxycyclohexane, polypropylene triol, polyethylenepropylene triol, glycerin, trimethylolpropane (TMP), triethanolamine, etc. Modified with triols, polypropylenetetraol, polyethylenepropylenetetraol, tetrafunctional or higher functional polyols such as castor oil, sucrose, sorbitol, 3,3'-dichloro-4,4'-diaminodiphenylmethane (MOCA), aniline, etc. Modified polyamines such as modified MOCA, aromatic amines such as toluene diamine, diphenylmethane diamine, diethyl toluene diamine, aliphatic amines such as ethylene diamine, polyamines such as Jeffamine ED, amino alcohols such as ethanolamine and diethanolamine, and Examples include mixtures of more than one species. As the curing agent combination system, MOCA-polyol combination curing agent, etc., which is a mixture of polyalkylene oxide and aromatic amine, can be mentioned.

The reaction temperature and reaction time for producing polyurethane may be appropriately set depending on the purpose, and preferably the reaction temperature is 20 to 220°C and the reaction time is 0.1 minute to 24 hours.

The coating method for polyurethane is not particularly limited, but examples include coating with a spatula, comb, roller, trowel, rake, etc., extrusion with a sealing gun, spraying, etc., hand coating, machine coating, etc. Accordingly, it can be made into any shape such as a coating film, a film sheet, or a thick object with any thickness. It is also possible to form a coating film or a cured product by blending a compound with anti-sag properties and applying it to vertical surfaces, walls, curved surfaces, depressions, etc. using a roller, ricing gun, airless gun, etc.

Specific uses of the polyurethane according to one embodiment of the present invention are not particularly limited, but include, for example, waterproof coatings for balconies and rooftops of buildings, waterproof sheets, waterproof coatings for vehicles, condominiums, etc. Examples include flooring materials for detached houses and hospitals, elastic paving materials for sports facilities, etc., sealants for civil engineering and construction, vehicle sealants such as direct glazing and body sealers, medical potting agents, and caulking for siding joints.
<Composition for sealing material>
The composition for a sealant of the present invention is preferably a one-component type because it forms a uniform composition, hardens, and tends to have excellent foaming resistance.
<Sealing material>
A sealing material according to one aspect of the present invention contains the above polyurethane.

As a method for applying the sealant, there is a method in which the sealant is usually filled in a sealing gun, applied directly to a base that has been washed or coated with a primer as necessary, and dried, and allowed to stand to harden. For automotive applications, examples include methods such as directly extruding a base material such as a steel plate coated with a primer as necessary and drying it at the required location, and bonding glass or the like to the base material and curing it with moisture in the air. In architectural applications, the adhesive surface is usually cleaned and a back-up material or bond breaker is applied. Apply masking tape around the joints and then apply a primer to the construction area. After that, the process is to fill target areas such as joints with a sealing gun, finish with a spatula, clean, and cure.

At that time, if the curable resin composition is viscous, it takes time to extrude it when filling the joints etc., which tends to deteriorate workability, so it is preferable that the cartridge extrusion time can be completed within 5 seconds. , more preferably within 4 seconds. If the sealant is too viscous, it may take time to clean the surrounding materials, and the curable resin composition may adhere to the spatula during spatula finishing, making installation and molding difficult. It is preferable that the composition has a viscosity such that it can be applied using a spatula or a trowel, and is easy to handle.

In the two-component type, a mixture of a base liquid containing a curable resin composition and a curing agent liquid is applied directly to a base that has been cleaned and primed and dried as necessary, and left to harden. Examples include methods such as applying the product directly to a base that has been washed or coated with a primer and drying as needed, while mixing with a machine, and allowing it to stand and harden.

Applications of the sealing material according to one embodiment of the present invention are not particularly limited, but include, for example, civil engineering/construction sealing materials, vehicle sealing materials such as direct glazing and body sealers, and the like.

EXAMPLES The present invention will be explained below with reference to Examples, but these Examples do not limit the present invention in any way. The raw materials and evaluation methods used in the following Examples and Comparative Examples are as shown below.
<Polyol>
In the Examples and Comparative Examples, a polyol having the structure shown in Formula (5) was used. The properties of the polyol are shown in Table 1.

The following materials were used as the raw materials listed in Tables 1 to 3.
<<Halogen-containing polyether polyol (A), (C)>>
Tetra-n-butylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and triisopropoxyaluminum are used in combination to thoroughly dehydrate and remove the solvent, and polypropylene glycol with a molecular weight of 400 (manufactured by Sanyo Chemical Industries, Ltd., product name: San By adding 17.3 mol equivalent of epichlorohydrin (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to Nix PP-400), a bifunctional halogen-containing polyether polyol (A) with a molecular weight of 2,000 was obtained. was created.

Furthermore, in the production of halogen-containing polyether polyol (A), the molecular weight was 1, A bifunctional halogen-containing polyether polyol (C) was prepared using 000.
<<Halogen-containing polyether polyol (B), (D)>>
Thoroughly dehydrate and remove solvent using a combination of tetra-n-butylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and triisopropoxyaluminum, and 1,6-hexanediol (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) A bifunctional halogen-containing polyether polyol (B) having a molecular weight of 2000 was prepared by adding 20.3 mol equivalent of epichlorohydrin (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) to the above solution.

Furthermore, in the production of the halogen-containing polyether polyol (B), by adding 9.5 mol equivalent of epichlorohydrin instead of adding 20.3 mol equivalent, a bifunctional halogen-containing polyether with a molecular weight of 1000 Polyol (D) was produced.
<<Halogen-containing polyether polyol (E)>>
Tetra-n-butylammonium bromide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) and triisopropoxyaluminum are used in combination to thoroughly dehydrate and remove the solvent, and polypropylene glycol with a molecular weight of 600 (manufactured by Sanyo Chemical Industries, Ltd., product name: San By adding 4.3 mol equivalent of epichlorohydrin (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) to Nix PP-600), a bifunctional halogen-containing polyether polyol (E ) was created.
<<Halogen-containing polyether polyol (F)>>
By adding epichlorohydrin to polypropylene glycol (manufactured by Sanyo Chemical Industries, Ltd., trade name: SANNIX PP-400) with a molecular weight of 400 using Lewis acid catalyst BF ₃ -Et ₂ O, the molecular weight becomes 2. A bifunctional polyether polyol (F) was prepared using 000.
<Isocyanate compound>
In all Examples and Comparative Examples, 4,4'-MDI (manufactured by Aldrich) was used as it was without purification.
(Analysis of polyol properties)
<Unsaturation degree>
It was measured according to the method of JIS-K1557-6.
<Molecular weight distribution (Mw/Mn)>
10 mg of polyol and 10 ml of THF were added to a sample bottle, dissolved by standing overnight, and a sample was obtained by filtering with a PTFE cartridge filter (0.5 μm).

RI detector RI8020 was used as a detector, and TSKgel GMR-HHRL x 2 in series and HLC-8020GPC were used as measurement columns (both manufactured by Tosoh Corporation).

The measurement conditions were a column temperature of 40°C, a flow rate of 1.0 ml/min, and a solvent of THF.The molecular weight distribution (Mw/Mn) was calculated using a cubic approximated curve using standard polystyrene manufactured by Tosoh Corporation as a calibration curve. An analysis was performed.

Production example (production of NCO-terminated prepolymer solution)
100 g of halogen-containing polyether polyol A was placed in a four-neck separable flask equipped with a stirring blade, and dehydrated under reduced pressure at 80° C. for 2 hours. After cooling to room temperature, 25 g of 4,4'-MDI was added under nitrogen and the reaction was carried out at 100°C. Prepolymer 1 was synthesized by back titrating the contents of the reactor with dibutylamine and stirring until the consumption of NCO groups stopped.

Prepolymers 2 to 8 were produced in the same manner as in the production example of Prepolymer 1, except that the predetermined amounts of the predetermined raw materials listed in Table 2 were used.

(Polyurethane evaluation method)
<Production of polyurethane sheet>
The prepolymer obtained in the NCO-terminated prepolymer synthesis example was coated onto a release-treated PET film (Teijin Film Solutions Co., Ltd., Purex A31) using an applicator (YOSHIMITSU SEIKI Co., Ltd.) to a thickness of 150 μm using a desktop coater. (manufactured by Mitsui Electric Seiki Co., Ltd., TC-1) at a speed of 1.0 m/min, and left to stand for 7 days in a constant temperature room at 23 to 25° C. and 50% RH to produce a polyurethane sheet.
<Breaking strength>
A JIS No. 3 dumbbell shape was punched out, and a tensile test was conducted at a tensile speed of 200 mm/min using a tensile testing machine (Tensilon TG-1210, manufactured by A&D Co., Ltd.) to measure the breaking strength. The measurements were carried out at 23 to 25°C in an atmosphere of 50% RH. The number of tests was 5 times, and the average value excluding the maximum and minimum values was calculated and used as the breaking strength.
A: 10 MPa or more B: 5 MPa or more and less than 10 MPa
C: Less than 5 MPa <tackiness>
The thumb was pressed against the prepared polyurethane and the resistance felt when peeled off was evaluated.
A: Almost no resistance B: Some resistance C: Sticky <transparency>
The haze of the produced polyurethane sheet was measured using a haze meter (NDH-5000, manufactured by Nippon Denshoku Kogyo Co., Ltd.).
A: Less than 5% B: 5% or more and less than 10% C: 10% or more Examples 1 to 5.
According to the evaluation method for polyurethane, polyurethane sheets were prepared using Prepolymers 1 to 5 and evaluated. All of the polyurethane sheets had high breaking strength, low tackiness, and high transparency.
Comparative example 1.
According to the evaluation method for polyurethane, a polyurethane sheet was prepared using Prepolymer 7 and evaluated. The transparency was good, but curing was poor, stickiness occurred, and the breaking strength was poor.
Comparative example 2.
According to the evaluation method for polyurethane, a polyurethane sheet was produced using Prepolymer 8 and evaluated. The breaking strength of the dumbbell pieces was strong, but when you pressed your thumb against the sheet surface, you felt a sense of resistance, and the transparency was low.
Comparative example 3.
According to the evaluation method for polyurethane, a polyurethane sheet was produced using Prepolymer 8 and evaluated. The breaking strength of the dumbbell pieces was poor, a feeling of resistance was felt when pressing the thumb against the sheet surface, and the transparency was low.

The above Examples 1 to 6 are shown in Table 3, and the results of Comparative Examples 1 to 3 are shown in Table 4.

(Evaluation as a sealing material)
<Preparation of sealing material>
To 100 parts by weight of the prepolymer obtained in the NCO-terminated prepolymer synthesis example, 80 parts by weight of heavy calcium carbonate (Whiten SB manufactured by Maruo Calcium Co., Ltd.) as a filler and Iganox 1010 (manufactured by BASF Corporation) as an antioxidant were added. 0.1 part by weight and 0.1 part by weight of bismuth octylate (Pucat 25, manufactured by Nippon Kagaku Sangyo Co., Ltd.) as a catalyst were added and kneaded in a kneader to obtain a paste-like sealant composition.

The obtained sealant composition was applied to a 25 mm wide SUS304 test piece (manufactured by Paltech, single side #320 HL) to a width of 5 mm and a thickness of 2 mm, bonded together and left to stand for 24 hours to proceed with curing, and then tested. A piece was prepared and evaluated as a sealing material.
<Curability>
After allowing the test piece obtained above to stand still for 24 hours, the feel when touching the sealant part with a finger was evaluated.
A: Not sticky B: Sticky C: Sealant sticks to fingers (not cured)
<Adhesiveness>
The test piece obtained above was subjected to a manual peel test, and evaluated by visually observing the fracture surface.
A: Cohesive failure B: Interfacial peeling <shear peeling strength>
Using a tensile tester (Tensilon TG-1210 manufactured by A&D), a shear peel test was conducted at a tensile speed of 50 mm/min to measure the shear peel strength.
A: 5 MPa or more B: 2 MPa or more, less than 5 MPa C: Less than 2 MPa Application example 1.
A sealing material was prepared using Prepolymer 3 according to the sealing material evaluation method, and evaluated. It was easy to apply and showed good curability, adhesion, and shear peel strength.
Application comparative example 1.
A sealing material was prepared using Prepolymer 6 and evaluated according to the evaluation method for sealing materials. During application, sag occurred and workability was poor, and it did not cure sufficiently, resulting in poor adhesion and shear peel strength.

Table 5 shows the results of the above application example.

Claims (7)

It is an NCO-terminated liquid urethane prepolymer,
The urethane prepolymer is
Contains a structural unit represented by formula (1) with a number average molecular weight of 200 or more and 3,000 or less, and
The degree of unsaturation is 0.020 meq/g or less,
The haze of the sheet obtained by coating with a thickness of 150 μm and standing in a constant temperature room at 23 to 25 ° C and 50% RH for 7 days is less than 10%,
Liquid urethane prepolymer with NCO group at the end:
In formula (1),
Q represents a polymer component containing a structural unit represented by formula [I],
m represents an integer from 2 to 8,
R ¹ represents an active hydrogen-containing compound residue;
In formula [I], X represents a halogen atom. A halogen-containing polyether polyol and an isocyanate compound, wherein the ratio of the total amount of NCO groups in the isocyanate compound to the total amount of OH groups in the halogen-containing polyether polyol (described as NCO/OH ratio) is 1.2 or more and 3.0 or less. The liquid urethane prepolymer according to claim 1, which is obtained by reacting a composition. The liquid urethane prepolymer according to any one of claims 1 to 2, wherein the degree of unsaturation is 0.016 meq/g or less. The liquid urethane prepolymer according to any one of claims 1 to 3, and one or more of fillers, other polyols, urethanization catalysts, foam stabilizers, antioxidants, and plasticizers. A liquid urethane prepolymer composition comprising. The liquid urethane prepolymer according to any one of claims 1 to 3 or the liquid urethane prepolymer composition according to claim 4 is cured by reaction with water in the air or a curing agent (active hydrogen-containing compound). Polyurethane that hardens. A composition for a sealant, comprising the liquid urethane prepolymer according to any one of claims 1 to 3 or the urethane prepolymer composition according to claim 4. A sealing material obtained by curing the sealing material composition according to claim 6 by reaction with water in the air or a curing agent (active hydrogen-containing compound).