JPH05117363A - Polyurethane resin composition - Google Patents

Abstract

PURPOSE:To obtain a polyurethane resin adhesive having a working life long enough to be low viscous and excellent in adhesion even after allowing it to stand in a molten state for 48hr and excellent in workability. CONSTITUTION:With 1,6-hexamethylene adipate having 3000 number-average molecular weight, 1,4-butanediol and bis(2,2'-diisocyanatophenyl)methane/bis (4,4'-diisocyanatophenyl) methane mixture [o-isomer/p-isomer =50/50 (weight ratio)] are reacted to obtain a polyurethane resin composition containing a linear polyurethane resin having 2-isocyanatophenyl-1-methyl end groups and showing a solid state at the ordinary temperatures.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a polyurethane resin composition.

[0002]

2. Description of the Related Art As a linear polyurethane resin having a terminal isocyanate group, 4-isocyanatephenyl-terminated terminals are used.
A 1-methyl group linear polyurethane resin is known.

[0003]

However, the above-mentioned polyurethane resin is extremely high in reactivity, has a short pot life, and immediately cures in a normal state, so that, for example, coating must be done quickly. Workability was extremely poor.

[0004]

Means for Solving the Problems The inventors of the present invention have made earnest studies in view of the above situation. Surprisingly, when the terminal isocyanate group of the polyurethane resin is a 2-isocyanatephenyl-1-alkyl group, the above-mentioned problems occur. The inventors have found that they can be solved and completed the present invention.

That is, the present invention provides a polyurethane resin composition containing a linear polyurethane resin having a terminal of 2-isocyanatephenyl-1-alkyl group as an essential component.

The 2-isocyanatophenyl-1-alkyl group at the terminal of the linear polyurethane resin in the present invention has the following chemical structure, for example.

[0007]

[Chemical 1] (R is an alkylene group which may have a branch.)

The polyurethane resin composition of the present invention is a linear polyurethane resin having a 2-isocyanatophenyl-1-alkyl group at its terminal [hereinafter, simply referred to as resin (1). ] Should be contained.

The resin (1) includes, for example, an active hydrogen-containing compound (A) having at least two active hydrogens, and bis (2,2)
It can be easily obtained by reacting the 2'-diisocyanatephenyl) alkane (B) as an essential component with the isocyanate group in the alkane (B) under an excess of the active hydrogen of the compound (A).

As the compound (A), a known and conventional active hydrogen-containing compound used for the production of ordinary polyurethane resins and an active hydrogen-containing compound having a hydrophilic group or a group which can be rendered hydrophilic by neutralization can be used.

The diol that can be used to obtain the resin (1) is, for example, a number average molecular weight of 50 to 10.
000, more specifically, polyester adipate such as polyethylene adipate glycol, polybutylene adipate glycol, polyhexamethylene adipate glycol, polyethylene ether glycol, polypropylene ether glycol, polytetramethylene ether glycol, polyhexamethylene ether glycol, etc. Polyether polyol, 2,2-bis (4,4
-Dihydroxyphenyl) propane 2 mol ethylene oxide adduct / polyether ester diol such as adipate diol, polymer diol such as polyamide diol, polyamide polyester diol, polycarbonate diol, and further ethylene glycol, propylene glycol, butylene glycol, hexamethylene glycol, Low-molecular-weight polyols such as octamethylene glycol, diethanolamine, tert-butyldiethanolamine, epsilon caprolactone, hydrazine,
Inorganic polyamines such as dimethylhydrazine, ethylenediamine, propylenediamine, isophoronediamine, cyclohexanediamine, dicyclohexylmethanediamine, p-phenylenediamine, metaphenylenediamine, 4,4'-diaminodiphenylmethane, 4,4'-
Diaminodicyclohexylmethane, 2,2-bis (4,
Organic amines such as 4-diamino-cyclohexyl) propane, N-monoethylol ethylenediamine, and tert-butylamine can be used. These may be used alone or in combination of two or more.

Of course, polybutadiene diol, polyorganosiloxane diols such as those described below, and fluorine-containing diols can also be used as the compound (A).

Examples of the active hydrogen-containing compound having a hydrophilic group which can become hydrophilic by neutralization include, for example, 2
-Oxyethanesulfonic acid, phenolsulfonic acid, sulfobenzoic acid, sulfosuccinic acid, 5-sulfoisophthalic acid, sulfanilic acid, 1,3-phenylenediamine-
4,6-disulfonic acid, 2,4-diaminotoluene-5
-Sulfonic acid-containing compounds such as sulfonic acid and derivatives thereof or polyester polyols obtained by copolymerizing these; 2,2-dimethylolpropionic acid, 2,2-
Dihydroxy monocarboxylic acids such as dimethylol butyric acid, 2,2-dimethylol valeric acid, dioxymaleic acid, 2,6-dioxybenzoic acid, carboxylic acid-containing compounds such as 3,4-diaminobenzoic acid, and derivatives or derivatives thereof. Polyester polyol obtained by copolymerization; polyoxyethylene-polyoxyalkylene copolymer having a molecular weight of 300 to 10,000, containing at least 30% by weight of ethylene oxide repeating units and containing at least one active hydrogen in the polymer. Examples thereof include nonionic group-containing compounds such as polymers, and polyester polyether polyols obtained by copolymerizing these compounds.

When an active hydrogen-containing compound having a group capable of becoming hydrophilic by neutralization is used, a neutralizing agent is optionally used.

Examples of the neutralizing agent at this time include non-volatile bases such as sodium hydroxide and potassium hydroxide, tertiary amines such as trimethylamine and triethylamine, and volatile bases such as ammonia. When the atomic group capable of becoming hydrophilic is a carboxyl group, it is preferable to use, for example, trimethylamine or triethylamine.

The alkane (B) used in the present invention is a bis (2,2'-diisocyanatephenyl) alkane, such as bis (2,2'-diisocyanatephenyl) methane or bis (2,2'-diisocyanatephenyl). Propane etc. are mentioned.

In obtaining the resin (1) according to the present invention, in addition to the above compound (A) and alkane (B), if necessary, for example, diisocyanate other than alkane (B), trimethylolpropane, penta Trifunctional or higher functional alcohols such as erythritol, trifunctional or higher functional carboxylic acids such as trimellitic acid and pyromellitic acid, trifunctional or higher functional amines, monoalcohols, monoamines and other active hydrogen-containing compounds, monoisocyanates, diisocyanates and trifunctional Isocyanate compounds such as the above isocyanates can be used.

Examples of the diisocyanate other than the alkane (B) include tolylene diisocyanate and bis (4,
4'-diisocyanate phenyl) methane, aromatic diisocyanates such as naphthalene diisocyanate, hexamethylene diisocyanate, lysine diisocyanate,
Cyclohexane diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate,
Examples thereof include aliphatic or alicyclic diisocyanates such as xylylene diisocyanate and tetramethylxylylene isocyanate.

These diisocyanates can be used alone or in combination of two or more kinds with the alkane (B).

Examples of combinations of alkane (B) and other diisocyanates include bis (2,2'-diisocyanatephenyl) methane (O-form) and bis (4,4).
Combination with 4'-diisocyanatephenyl) methane (P-form), bis (2,2'-diisocyanatephenyl) methane, bis (4,4'-diisocyanatephenyl) methane, and aliphatic diisocyanates and / or fats There are combinations with cyclic diisocyanates.

In the case of adopting the former combination, when the total amount of O-form and P-form is 100 parts by weight, O-form / P-form (weight ratio) is 20% by weight or more and less than 100% by weight, Above all, it is preferable to set it to 35 to 60% by weight.

When the latter combination is adopted and the preparation is carried out using a mixture of O-form / P-form as described above, the mixture of O-form / P-form, aliphatic diisocyanate and / or Total of 1 with alicyclic diisocyanate
When the amount is 00 parts by weight, the (O-form / P-form mixture) / (aliphatic diisocyanate and / or alicyclic diisocyanate) weight ratio is preferably 60 to 20% by weight.

When an alkane (B) is used in combination with an aliphatic diisocyanate and / or an alicyclic diisocyanate, a cured product of the resin (1) obtained in combination with the cured product of the resin (1) obtained without the combination is used. Of the above tends to have better light resistance.

The resin (1) is obtained by reacting, for example, the compound (A) and the alkane (B) at the same time as essential components, or the compound (A) and the diisocyanate other than the alkane (B) and / or (B). It is possible to obtain it by preliminarily obtaining a urethane prepolymer having terminal active hydrogen as an essential component, and reacting this with the alkane (B) as an essential component.

The reaction ratio of the active hydrogen atom of the compound (A) with all isocyanate and the isocyanate group is not particularly limited, but is usually 1: 1.1 to 1: 4, preferably 1: 1.5. ~ 1: 2.

The reaction conditions are not particularly limited, but, for example, in an inert gas stream, usually at a moderate temperature of 40 to 150 ° C., preferably 60 to 100 ° C., and 0.5 to 12.
The time is continued until the isocyanate group concentration becomes constant.

In producing the resin (1) according to the present invention, a catalyst and a stabilizer can be used if necessary. Examples of the catalyst include nitrogen-containing compounds such as triethylamine, toluethylenediamine and morpholine, metal salts such as potassium acetate, zinc stearate and tin octylate, and organometallic compounds such as dibutyltin dilaurate. These catalysts can be added at any stage during the production of the polyurethane resin. When the polyurethane resin composition containing the resin (1) according to the present invention is used as an adhesive, it is desirable to add it in consideration of heat stability and moisture curability.

The resin (1) according to the present invention usually has a weight average molecular weight of 2000 to 200,000, and particularly 2000 to 10.
It is preferably 0000.

The above reaction may be carried out in the presence of an organic solvent, if desired, or an organic solvent may be added after the reaction.

As the organic solvent, for example, dimethylformamide, dimethylacetamide, dimethylsulfoxide, cyclohexanone, methyl ethyl ketone, methyl-
n-propyl ketone, methyl isobutyl ketone, ethyl acetate, butyl acetate, acetone, tetrahydrofuran, dioxane, toluene, n-hexane, cyclohexane, methanol, ethanol, isopropyl alcohol, n-
Examples include blanol, iso-butanol, tert-butanol, methyl cellosolve, ethyl cellosolve, ethyl cellosolve acetate and the like, and these are used alone or in combination of two or more kinds.

The resin (1) in the polyurethane resin composition of the present invention may be solventless liquid or solid.

The composition containing the solventless liquid or solid polyurethane resin (1) of the present invention can be used as it is as a moisture-curable reactive hot melt adhesive. or,
If the above-mentioned active hydrogen-containing compound is used as a cross-linking agent in the polyurethane resin (1) as required, the tear strength and adhesiveness of the film tend to be improved as compared with a cured product of the polyurethane resin (1) alone. .

If the mixture of the polyurethane resin (1) and the active hydrogen-containing compound is liquid at room temperature, it can be used as a two-component liquid adhesive. In the preparation of this two-pack type liquid adhesive, when a polyester diol having a number average molecular weight of 400 to 4000, particularly a liquid polyester diol having a number average molecular weight of 400 to 4000 having a branched alkyl group is used as the active hydrogen-containing compound, the crosslinking point The distance between them can be increased, the mesh structure can be increased, and the strength and adhesiveness of the cured film can be further improved.

When the polyurethane resin (1) has a hydrophilic group or a group which can be made hydrophilic by neutralization with a neutralizing agent, it is used as an adhesive,
By immersing the adhered adherends in water, the resin (1) can be removed from the adherend even after the resin (1) is cured.
Can be separated and the adherend can be reused.

In the polyurethane resin composition of the present invention, if necessary, an antioxidant, an ultraviolet absorber, a hydrolysis inhibitor, a pigment, a dye, a thickener, an antifoaming agent, a surfactant, an antistatic agent, Flame retardants, deodorants, dispersants, tackifier resins, fillers, cross-linking agents and the like can be added.

In the present invention, together with the above-mentioned polyurethane resin, if necessary, other resins usually used, such as polyurethane resin, vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl propionate copolymer, It is also possible to use polyvinyl butyral resin, fibrin resin, polyester resin, epoxy resin, phenoxy resin, polyamide resin and the like together.

[0037]

EXAMPLES Next, the present invention will be described by way of examples, but this is only one mode and the present invention is not limited to the examples. All “parts” and “%” in the text are based on weight.

Example 1 300 parts of 1,6-hexanediol adipate having a number average molecular weight of 3000 was placed in a 3 liter cylindrical flask equipped with a condenser, a thermometer and a turbine stirrer.
A mixture of 30 parts of 4-butanediol, bis (2,2'-diisocyanatephenyl) methane and bis (4,4'-diisocyanatephenyl) methane (weight ratio 50 /
50) 225 parts were charged and reacted at 100 ° C. for 5 hours.
The composition of the obtained polyurethane resin had a 2-isocyanate phenyl-1-methyl group at the terminal, the isocyanate group content was 6.0%, and the viscosity at room temperature solid at 100 ° C. was 180 ps. Is referred to as a hot melt adhesive [A].). The adhesive [A] was tested for viscosity stability at high temperature, pot life, and adhesiveness. The results are shown in Table 1. The adhesion test was carried out by the following method. The tensile shear strength was measured using an AS plate of an acrylonitrile / styrene copolymer and a chromate-treated cold rolled steel plate in accordance with JIS-K6850. As a test method, a composition melted at 150 ° C. was applied on the steel plate side at 20 g / m 2, and immediately thereafter, an AS plate was pressure-bonded. Tensile shear strength was measured 5 hours after pressure bonding.

Comparative Example 1 The same operation was performed except that 225 parts of bis (4,4'-diisocyanatephenyl) methane was used as the isocyanate mixture, and 4-isocyanatophenyl-1 was added to the terminal.
-A hot melt adhesive [B] comprising a composition of a polyurethane resin having a methyl group was obtained. This composition [B]
Has an isocyanate group content of 5.8% and a solid content at room temperature of 10
The viscosity at 0 ° C was 260 ps. Using this adhesive [B], the same physical property test as in Example 1 was conducted. The results are shown in Table 1.

[0040]

[Table 1]

Example 2 700 parts of polyoxypropylene glycol having a number average molecular weight of 3000 and 3-methylpentanediol adipate 30 having a number average molecular weight of 1000 were placed in a 3 liter cylindrical flask equipped with a condenser, a thermometer and a turbine stirrer.
0 parts were charged, and then a mixture of bis (2,2'-isocyanatophenyl) methane and bis (4,4'-isocyanatophenyl) methane (weight ratio 50/50) 185
Parts and 84 parts of 4,4'-methylenebiscyclohexyl isocyanate were charged and reacted at 100 ° C for 5 hours. The composition of the obtained polyurethane resin has a 4-isocyanatephenyl-1-methyl group at the terminal, the isocyanate group content is 3.5%, and the viscosity at room temperature is 560 ps.
Met. To 150 parts of this composition, CLAPOL P-20
100 parts of 10 [3-methylpentanediol adipate manufactured by Kuraray Co., Ltd., number average molecular weight 2000] were mixed,
A two-component adhesive [C] was obtained. This adhesive [C] was used to measure the compounding stability over time and the physical properties of the cured sheet.
The results are shown in Table 2. The pot life, the production of the cured sheet and the measurement were carried out by the following methods. Pot life: The pot life was defined as the time that doubled the initial viscosity. Preparation of hardened sheet: Coated on release paper to a thickness of 0.1 mm and hot-dried at 70 ° C for 2 minutes and 150 ° C for 3 minutes to prepare a sheet. Then, the physical properties of the sheet were measured by an autograph (manufactured by Shimadzu Corporation).

Example 3 276 parts of dipropylene glycol, 236 parts of 3-methylpentanediol, 292 parts of adipic acid, 166 parts of isophthalic acid, dimethyl 5-sodiumsulfoisophthalate 1
48 parts were charged, and dehydration reaction was carried out at 210 ° C. for 5 hours and at 240 ° C. for 10 hours to obtain polyester diol A having a number average molecular weight of 2000 and 4% sodium sulfonate group in the molecule. This polyester diol A (1000 parts), a mixture of bis (2,2'-diisocyanate phenyl) methane and bis (4,4'-diisocyanate phenyl) methane (weight ratio 50/50) (125 parts), and isophorone diisocyanate (111 parts) were charged. Reacted at 20 ° C. for 20 hours. The composition of the obtained polyurethane resin has 2-
Has an isocyanate phenyl-1-methyl group,
The isocyanate group content was 3.4%, and the viscosity at room temperature was 1260 ps. 150 parts of this composition was mixed with 100 parts of Curapol P-2010 to obtain a two-component adhesive [D]. This adhesive was used in Example 2 using [D].
The same test was conducted. The results are shown in Table 2.

[0043]

[Table 2]

As can be seen from the respective tables, it is clear that the adhesive using the polyurethane resin composition of the present invention is superior in compounding stability and easy in workability as compared with the conventional adhesives. Is.

[0045]

EFFECTS OF THE INVENTION Since the polyurethane resin composition of the present invention uses a linear polyurethane resin having a 2-isocyanatophenyl-1-alkyl group at the terminal as the polyurethane resin, it has a usable life based on the reaction of the isocyanate group. It has a remarkable effect that it can be used for a long time and the workability is improved. Further, there is also an effect that the alohanate reaction hardly occurs even if it is kept at a high temperature for a long time, and the thickening phenomenon hardly occurs.

Claims (6)

[Claims] 1. A terminal of 2-isocyanate phenyl-1.
A polyurethane resin composition containing an alkyl group linear polyurethane resin as an essential component. 2. A linear polyurethane having an end isocyanate group obtained by reacting an active hydrogen-containing compound (A) having at least two active hydrogens with a bis (2,2'-diisocyanatephenyl) alkane (B) as an essential component. A polyurethane resin composition containing a resin. 3. The composition according to claim 2, wherein the linear polyurethane resin having an isocyanate group at the end is reacted with bis (4,4′-diisocyanatephenyl) alkane in combination. 4. The composition according to claim 2, wherein the linear polyurethane resin having an isocyanate group at the end is reacted with an aliphatic diisocyanate and / or an alicyclic diisocyanate in combination. 5. The composition according to claim 1, wherein the compound (A) is a polymer diol having a hydrophilic group. 6. A terminal of 2-isocyanate phenyl-1
A two-component polyurethane resin composition comprising an alkyl group linear polyurethane resin and an active hydrogen-containing compound having at least two active hydrogens.