WO2002044238A1

WO2002044238A1 - Thermosetting urethane composition

Info

Publication number: WO2002044238A1
Application number: PCT/JP2001/010180
Authority: WO
Inventors: Tetsuaki Fukushima; Makoto Ohkubo
Original assignee: Kao Corporation
Priority date: 2000-11-28
Filing date: 2001-11-21
Publication date: 2002-06-06
Also published as: JP2002161125A; JP4536249B2

Abstract

A one-pack type thermosetting urethane composition which has such curing characteristics as to attain high strength and elastomeric properties and is useful as sealing material. The composition comprises a urethane prepolymer and/or a poly- isocyanate compound which has blocked isocyanate groups and a polyamine represented by the general formula (1): (1) wherein R is a linear or branched hydrocarbon group having 8 to 22 carbon atoms; x is a number of 1 to 5; and y and z are each a number of 0 to 5, with the proviso that both of y and z are not simultaneously 0.

Description

Description Thermosetting urethane composition

TECHNICAL FIELD The present invention relates to a thermosetting urethane composition which is useful for sealing joints and gaps in spot welding of press-formed steel sheets.

Conventional technology Conventionally, in production lines such as automobiles and refrigerators, there is no need to measure and mix sealing materials that seal joints and gaps such as spot welding of press-formed steel sheets, which limits pot life. One-part type thermosetting sealing materials have been used. Such a one-part type thermosetting sealing material is a PVC base composition in which a polyvinyl chloride (PVC) powder is dispersed in a plasticizer, and an adhesive, a stabilizer, a filler and the like are compounded. Although so-called PVC plastisol-based sealing materials have been frequently used, due to recent environmental issues, the use of urethane prepolymers as a main component has been shifting to thermosetting polyurethane resins. For example, a urethane system containing a fine powder as disclosed in Japanese Patent Application Laid-Open No. H10-155853 is known, but has come to exhibit the physical properties that can be changed to PVC, in particular, adhesiveness. Not. Also, Japanese Patent Application Laid-Open No. 60-252519 discloses a solid polyisosocyanate in which an isocyanate group is inactivated by reacting a solid polyisocyanate compound with an inactivating agent such as an amidine compound or a guanidine compound. Although a cured product formed by dispersing a phosphate compound in a polyol component is disclosed here, the hardness is too high and is far from rubber elasticity like PVC. Adhesion was poor and there was a drawback that it was extremely impractical.

DISCLOSURE OF THE INVENTION An object of the present invention is to provide a one-pack type thermosetting urethane composition having high-strength rubber elastic curing properties and useful for sealing materials.

The present invention relates to a resin prepolymer (hereinafter, referred to as an NCO block prepolymer) and a polyisocyanate compound (hereinafter, referred to as an NCO block polyisocyanate) having an isocyanate group blocked by a blocking agent. And a polyamine represented by the following formula (1) (hereinafter referred to as polyamine (1)).

In the formula, R represents a linear or branched hydrocarbon group having 8 to 22 carbon atoms, X represents a number of 1 to 5, and y and z each represent a number of 0 to 5. However, y and z never become 0 at the same time. The sealing cured according to the present invention has excellent adhesiveness, curability and rubber elasticity.

DETAILED DESCRIPTION OF THE INVENTION The NCO block prepolymer in the present invention is an It is a product obtained by reacting a blocking agent with a terminally active isocyanate group-containing polyurethane prepolymer obtained by reacting a lysocyanate compound.

Examples of the polyol component include polyhydric alcohols such as ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, sorbitol, and sucrose, and alkylene oxides such as ethylene oxide or propylene oxide. Polyoxyalkylene ether polyols obtained by addition polymerization of: ethylene glycol, propylene dalycol or oligoglycols thereof; butylene glycol, hexylene glycol, polytetramethylene ether glycols; polycaprolactone polyol Polyester polyols such as polyethylene adipate; polybutadiene polyols; higher fatty acid esters having a hydroxyl group such as castor oil; polyether polyols or polyether polyols; Polymer polyols obtained by grafting a vinyl monomer to an ester polyol, and the like, include polyoxyalkylene ether polyols having 2 to 3 hydroxyl groups in one molecule and having a hydroxyl equivalent of 500 to 300. Are preferred.

The polyisocyanate compound is appropriately selected from aromatic, aliphatic or alicyclic polyisocyanates. For example, tolylene diisocyanate (TDI), diphenyl methanediisocyanate (MDI), 3, 3 '-Dimethyl_4,4'-biphenylene diisocyanate, 1,4-phenylene diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, naphthylene diisocyanate, norbornane diisocyanate 1,4'-diisocyanate, crude TDI, polymethylene polyphenylisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, 1,4-tetra Methylene diisocyanate, 1,5-pentene methylene diisocyanate, 2,2,4-trimethyl-1,6-hexamethylene diisocyanate, 1,3-bis (isosinetomethyl) one Examples thereof include cyclohexane, hydrogenated xylylene diisocyanate, their isocyanurate, carpoimidide, and burette, and one or more of these can be used.

The reaction between the polyol component and the polyisocyanate compound is carried out at a temperature such that the OH group of the polyol / NCO group of the polyisocyanate becomes 1 / 1.2 to 3.5 in an equivalent ratio, and from room temperature to 90 ° C. For 1 to 7 hours. For this reaction, if necessary, a reaction solvent, for example, ethyl acetate, toluene, xylene, etc., a catalyst, for example, an organic tin catalyst such as dibutyltin dilaurate, a bismuth catalyst such as bismuth octoate, A tertiary amine catalyst such as 4-diaza [2.2.2] bicyclooctane may be present.

A block for obtaining an NC-block prepolymer by reacting a NC-group of a urethane prepolymer containing a terminally active isopropyl group obtained by a reaction between a polyol component and a polyisocyanate compound with a blocking agent. The conversion ratio (equivalent ratio of the NCO group of the terminally active isocyanate group-containing urethane prepolymer to the active hydrogen of the blocking agent) is preferably 0.90 to 1.15 from the viewpoint of storage stability and strength. 0 · 95 to 1.05 is more preferred.

The blocking reaction is preferably performed at 40 to 60 ° C for 0.5 to 3 hours. Examples of the blocking agent include phenols such as phenol, cresol, xylenol, and ethyl phenol; lactams such as ε-force prolactam, δ-valerolactam, 3-butyrolactam, β-propiolactam; Oximes such as shim, acetamidoxime, acetoxime, methylethylketoxime, diacetylmonoxime, benzophenoneoxime, cyclohexanone oxime, etc .; getyl malonate, dimethyl malonate, ethyl acetate, acetoacetate Active methylenes such as methyl acetate and acetylacetone; methanol, ethanol, propanol, isopropanol, butanol, 2-ethylhexanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether Alcohols such as benzotriazoles; mercaptans; acid amides; imides; amines; imidazoles; urea and the like blocking agents, especially phenols, lactams, and oximes Blocking agents are preferred.

In the present invention, the NCO-blocked polyisocyanate is obtained by masking the active isocyanate group of the above-mentioned isocyanate compound with a blocking agent as in the case of the NCO-block prepolymer.

In the present invention, an NCO block prepolymer, an NCO block polyisocyanate, or a mixture thereof can be used as the isocyanate component. In the present invention, the polyamine (1) can be used as a solid or a liquid, but it is more preferable to use an amine which is liquid at ordinary temperature from the viewpoint of workability. R in the general formula (1) may be a single hydrocarbon group or a mixed hydrocarbon group, and preferably has 8 to 18 carbon atoms from the viewpoint of rubber elasticity, and has 8 to 12 carbon atoms. Is more preferable, and X is preferably 1 to 2, and particularly preferably 1 is in terms of adhesion and rubber elasticity. y and z are preferably numbers such that their sum is 1 to 4, and particularly preferably 1 to 3.

Specific examples of the polyamine (1) include N-octyl-N_aminopropyl-N, -Aminopropylpropylenediamine, N-lauryl-1-N-aminopropyl-1-N '-Aminopropylpropylenediamine, N-myristyl-N-Aminopropyl-1-N'-aminopropylpropylenediamine, N-octyl-N —Aminopropyl—N,, N′—di (aminopropyl) propylenediamine and the like. Polyamine (1) can be produced, for example, by a known method described in JP-A-12-34259.

In the present invention, NC 0 The block prepolymer primary and Z or NC 0 block poly Isoshianeto with polyamines (1), the equivalent ratio of NH ₂ with respect to NCO groups, NH ₂ / NCO is 0. 7: the L 1 5. It is preferable to mix them so as to be 0.8 to 1.10 more preferably.

In the present invention, an aromatic or aliphatic amine other than polyamine (1) such as 0-phenylenediamine, m-phenylenediamine, 2,3-tolylenediamine, 2,4- Aromatic amines such as tolylenediamine, 2,5-tolylenediamine, 2,6-tolylenediamine, 3,4-tolylenediamine, 1,12-dodecanediamine, 1,10_decanediamine, 1,8-octanediamine, 1,14-tetradecane Aliphatic amines such as diamine and 1,16-hexadecandiamine can also be used in combination.

In the present invention, a powder may be used in combination for the purpose of improving strength or the like. The powder can be used arbitrarily from inorganic or organic ones.Examples include inorganic oxides such as titanium oxide, calcium carbonate, clay, silica, zirconia, carbon, alumina, talc, etc. Examples thereof include vinyl chloride, polyacrylic resin, polystyrene, and polyethylene. One or a mixture of two or more of these may be used. The thermosetting polyurethane composition of the present invention contains an NC block prepolymer and / or an NCO-blocked polyisocyanate and a polyamine (1). If necessary, the physical properties of the cured product, especially the compression An appropriate amount of a bifunctional or higher epoxy resin may be blended in order to impart strong durability against distortion and the like. Examples of the epoxy resin include bisphenol A-type, F-type, AD-type, phenol-type, cresol-type, cyclic aliphatic, and glycidyl ester-based epoxy resins, and liquid resins are particularly preferable. From the viewpoint that the physical properties of the epoxy resin can be expected and that the rubber physical properties of the cured polyurethane resin are not impaired, the isocyanate component 1 composed of NCO block prepolymer 1 and Z or NC 0 block polyisocyanate is used. It is preferably used in an amount of 1 to 15 parts with respect to 100 parts (parts by weight, the same applies hereinafter).

The composition of the present invention may optionally contain a urethane catalyst. Preferred examples thereof include DBU [1,8-diazabicyclo (5.4.0) indene-1 7] and DBU phenol salt. , DBU octylate, DBU formate, etc .; monoamines (triethylamine, etc.), diamines (N, N, Ν ', Ν'-tetramethylethylenediamine, etc.), triamines (tetramethyldanidine, etc.) ), Cyclic amines (such as triethylenediamine), alcoholamines (such as dimethylaminoethanol), and etheramines such as bis (2-dimethylaminoethyl) ether; dibutyltin dilaurate, tin octoate, octylic acid Metal salts of organic carboxylic acids such as lead and zinc octylate; and imidazole catalysts such as 2-methylimidazole and 1,2-dimethylimidazole.

Further, the composition of the present invention may optionally contain a plasticizer. Preferred specific examples include dibutyl phosphate, di (2-ethylhexyl) phthalate, Octyl phthalate, dicyclohexyl phthalate, diisooctyl phthalate, diisononyl phthalate, diisodecyl phthalate, dibenzyl phthalate, butyl benzyl phthalate, trioctyl phosphate, epoxy plasticizer, toluene-sulfonamide, chloroparaffin And adipic acid esters. Further, the composition of the present invention may contain a solvent. At this time, it is preferable that the solvent has a small polarity, and a solvent such as an aliphatic hydrocarbon, an aromatic hydrocarbon, an alicyclic hydrocarbon, a halogenated hydrocarbon, an ether, an ester, or a ketone is used. In particular, an aliphatic hydrocarbon solvent is preferable.

The composition of the present invention may further contain, if necessary, other additives usually used in the art, such as a filler, a thixotropic agent, an ultraviolet absorber, an antioxidant, a dye / pigment, an adhesive, and a dewatering agent. And the like may be blended in an appropriate amount.

The composition of the present invention has good storage stability, and the cured product formed from the composition of the present invention has very good curability (hardness) and adhesiveness. Good handling and workability during manufacturing. Applicable to environmental safety. Furthermore, it has excellent rubber elasticity and is practical. Example

Synthesis example 1

Stearylamine (270 g, 1 mol) was placed in a flask, heated to 60 ° C., and acrylonitrile (58.3 g, 1.1 mol) was added dropwise over 2 hours. After completion of the dropwise addition, the mixture was stirred at 95 ° C for 5 hours to obtain a cyanoethylated product. 350 g of the obtained cyanoethylated product and 4 g of Raney nickel were placed in an autoclave, the temperature was raised to 130 ° C., hydrogen was introduced, the pressure was maintained at a constant L 47 MPa, and a hydrogenation reaction was carried out for 5 hours. After the reaction, cool Mono-nickel was removed by filtration and purified by distillation to obtain N-stearyl-N-aminopropylpropylenediamine. The obtained amine (162 g, 0.5 mol) was placed in a flask, heated to 60 ° C., and acrylonitrile (67 g, 1.25 mol) was added dropwise over 2 hours. After completion of the dropwise addition, the mixture was stirred at 95 ° C for 5 hours to obtain a cyanoethyl compound. 150 g of the obtained cyanoethylated product and 2 g of Raney nickel were placed in a autoclave, the temperature was raised to 130 ° C., hydrogen was introduced, the pressure was maintained at a constant pressure of 1.47 MPa, and a hydrogenation reaction was performed for 5 hours. After completion of the reaction, the reaction mixture was cooled, Raney nickel was removed by filtration, and distillation purification was performed to obtain stearyltetramine (compound of formula (1) where ¾ = stearyl group, x = y = lz = 0). The total amine value was 510 mgK0H / g, the partial amine value was 252 mgK0H / g, and the structure was identified using a separately synthesized sample.

Synthesis example 2

N-lauryl-N-aminopropylpropylenediamine was obtained in the same manner as in Synthesis Example 1 except that laurylamine (185 g, 1 mol) was used instead of stearylamine, and similarly, lauryltetramine (in the formula (1)) R lauryl group, x = y = lz = 0). Incidentally, the total amine value was 634 mgKOH and the partial amine value was 312 mgKOH / g.

Synthesis example 3

Octylpropylenediamine (185 g, 1 mol) was placed in a flask and heated to 60, and then acrylonitrile (169.6 g, 3.2 mol) was added dropwise over 2 hours. After completion of the dropwise addition, the mixture was stirred at 95 ° C for 5 hours to obtain a cyanoethyl compound. 355 g of the obtained cyanoethylated compound and 3.6 g of Raney nickel were put in an autoclave, and octylpenamine (R octyl group in the formula (1), X = y = z = One Compound) was obtained. The total amine value was 783 mgK0H / g and the partial amine value was 310 mgKOH / g. Synthesis example 4

Tallow alkyl propylene diamine (321 g, 1 mol) was placed in a flask, and the temperature was raised to T (T), and then acrylonitrile (111.3 g, 2.1 mol) was added dropwise in 2 hours. Subsequently, 345 g of the obtained cyanoethylated compound and 4 g of Raney nickel were placed in an autoclave, and a hydrogenation reaction was carried out under the same conditions as in Synthesis Example 1. After completion of the reaction, cooling was performed. Raney nickel was filtered off to obtain the target amine, which was a compound whose main component was R tallow alkyl group in the formula (1) and x = y = lz = 0. The value was 513 mgK0H / g and the partial amine value was 259 mgK0H / g.

Synthesis example 5

Using lauryl propylene diamine (241 g, 1 mol) and acrylonitrile (169.6 g, 3.2 mol), the target amine was obtained in the same manner as in Synthesis Example 4. This was a compound whose main component was R = lauryl group and x = y == l z = 0 in formula (1). The total amine value was 679 mgK0H / g and the partial amine value was 284 mgK0H / g.

Synthesis Example 6

The desired amine was obtained in the same manner as in Synthesis Example 4 using propylenediamine (314 g, 1 mol) and acrylonitrile (138.7 g, 2.6 mol). It contained 58% by weight of a compound represented by the formula (1) where R = hardened tallow alkyl group and x = y = lz = 0. The total amine value was 552 mgK0H / g and the partial amine value was 256 mgKOH / g.

Synthesis Example 7 Using tallow dipropylene triamine (378 g, 1 mol) and acrylonitrile (169.6 g, 3.2 mol), the target amine was obtained in the same manner as in Synthesis Example 4. This compound contained 44% by weight of a compound represented by the formula (1) where R = tallow alkyl group, x = l, y = 2, z = 1 in the formula (1). The total amine value was 537 mgK0H / g and the partial amine value was 245 mgK0H / g.

Synthesis Example 8

Tolylene diisocyanate (TD I) is reacted with polyoxypropylene ether diol having a hydroxyl equivalent of 1,500 at 80 ° C for 2 hours at an equivalent ratio of OH group, ZNCO group = 1Z2.2, and a terminal active NCO group-containing urethane. Prebolimer was obtained. Next, ε-force prolactam or acetoxime as a blocking agent was added to acetoxime or ε-force prolactam at 80 ° C for 2 hours at a ratio such that the NCO-based active hydrogen group (equivalent ratio) becomes 1Z1.05. The reaction was carried out under the following conditions to obtain lactam-based and oxime-based NC〇 block prepolymers, respectively. The NCO% of these NCO block prepolymers was 13%.

Examples 1 to 14 and Comparative Examples 1 to 6

Lactam- or oxime-based NCO block prepolymer 1 'obtained in Synthesis Example 8, 1,12-dodencandiamine (Tokyo Kasei Kogyo Co., Ltd.) as a polyamine obtained in Synthesis Examples 1 to 7 or a comparative polyamine. ), Amine value 278mgK0H / g), 1,9-nonandiamine (manufactured by Tokyo Kasei Kogyo Co., Ltd., amine value 350mgKOH / g), 4,4'-methylene-bis-1-2-methylcyclohexylamine (manufactured by BASE) , Amine value

267 mg K0H / g), and were mixed at the ratios shown in Table 1 and heated and mixed and dispersed at 100 ° C. for 7 minutes with a Chemis Irrigation to prepare a one-part type thermosetting urethane composition. This composition The performance of the product was evaluated by the following method. Table 1 shows the results.

Performance evaluation method>

Storage stability:

It was stored tightly closed at 40 ° C, the increased viscosity after 7 days was measured, compared with the initial viscosity immediately before storage, and evaluated according to the following criteria.

〇; viscosity change rate less than 50%

X: Viscosity change rate 50% or more

Baking ability:

After coating on a release paper with a dry film thickness of 2 and baking and curing under the three conditions shown in Table 1, the curability of the cured film to be formed is indicated by JISA hardness, and the adhesion is evaluated based on the following criteria. did.

〇: cohesive failure, Δ: interface fracture

:table 1

Actual fl £ Example Ratio ¾ ¾ Example

1 2 3 4 5 6 7 8 9 10 11 12 13 14 1 2 3 4 5 6

NCO Bunk Lactam 100 100 100 100 100 100 100 100 100 Prepolymer

(Parts) Oxime 100 100 100 100 100 100 100 100 100 100 100

Synthesis example 1 7 10.6 1 1

Synthesis Example 2 6 8

Synthesis example 3 ^{4 1} 4.5 5.5

Synthesis example 4 7.5 10

Synthesis Example 5 5.7 6

Polyamine

(Part) Synthesis example 6 6 8.5

Synthesis example 7 ^{4 1} 8

1,12—dodecanediamine 9.5 8

1,9-nonandiamine 7 5.5

4,4'-methylene-bis-2-methyl

6.5 10 Lecyclohexylamine

NH ₂ / NCO equivalent ratio 0.73 1.10 1.15 0.78 1.04 0.86 1.05 0.77 1.03 0.91 0.96 0.72 1.02 0.94 1.06 0.89 0.99 0.78 0.70 1.08 Calcium carbonate ⁴² (parts) 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 100 Plasticizer (diisononyl phthalate) (parts) 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30 30

40 ° C storage stability 〇 O 〇〇 O 〇〇〇〇 0 〇〇〇〇〇 X 〇 X 〇〇 X

Curability 24 22 20 24 25 22 23 22 22 26 24 22 24 23 20 Gelation 19 Gelation Gelation 19

1 30 ° C X 30 minutes

Adhesion Δ O 〇〇〇〇〇〇〇〇〇〇〇 O Δ-Δ-― Δ

Curing 26 24 23 27 27 25 27 25 27 28 28 28 28 28 22 20 22 Ge gelation 22

1 40 ° C X 30 minutes

Adhesion O 〇〇〇 O 〇〇〇 O 〇〇〇 O 〇 Δ △ △ Δ

Curability 33 30 29 32 34 30 32 32 33 35 32 32 32 32 22 22 24 20 24 20

1 50 ° C X 30 minutes

Adhesive 〇〇 O 〇〇 O 〇〇〇〇〇〇 O 〇〇 O 厶〇〇〇〇〇

note)

* 1: Used as bifunctional

* 2: Calcium carbonate surface-treated with fatty acids

Claims

The scope of the claims

1. A thermosetting urethane composition containing at least one urethane prepolymer and a polyisocyanate compound having an isocyanate group blocked by a blocking agent, and a polyamine represented by the formula (1).

In the formula, R is a straight-chain or branched-chain hydrocarbon group having 8 to 22 carbon atoms, X is a number of 1 to 5, y and z are each a number of 0 to 5, where y and z are simultaneously 0 and It will not be.

2. The equivalent ratio of the NH ₂ group of the polyamine represented by the formula (1) to the NC〇 group of the urethane prepolymer and the polyisocyanate compound having an isocyanate group blocked by the blocking agent, and NH ₂ ZNCO is 0 The composition according to claim 1, wherein the composition is 7 to 1.15.

3. The composition according to claim _{2, wherein} NH2ZNCO is 0.90 to 1.15.

4. The composition according to claim 1, further comprising a polyamine other than the formula (1), a powder, a bifunctional or higher epoxy resin, a urethane catalyst, a plasticizer or a solvent.