WO2001088010A1

WO2001088010A1 - Hybrid thermosetting material composition

Info

Publication number: WO2001088010A1
Application number: PCT/JP2000/003121
Authority: WO
Inventors: Kenta Nakayama; Hitoshi Ohno; Takashi Minamihori
Original assignee: Sunstar Giken Kabushiki Kaisha; Uni-Sunstar B.V.
Priority date: 2000-05-16
Filing date: 2000-05-16
Publication date: 2001-11-22
Also published as: JP3776353B2

Abstract

A hybrid thermosetting material composition useful as, e.g., an automotive body sealer in automotive body assembly lines; and a method of preventing the foaming occurring during sealing in the assembly lines. The composition is characterized by comprising: a plastisol material comprising thermoplastic resin particles and a plasticizer; a blocked urethane prepolymer obtained by blocking the free isocyanate groups of an isocyanate-terminated urethane prepolymer; and a hardener therefor. The method of foaming prevention is characterized by comprising applying the hybrid thermosetting material composition, subsequently heating the coating to cause the plastisol material to gel during heating from 60 to 100°C, and then further heating it to 100°C or higher to thermally cure the blocked urethane prepolymer.

Description

Description Hybrid thermosetting material composition

Technical field

The present invention relates to a hybrid thermosetting material composition, and more specifically, from 60 ° C. to 10 ° C.

A hybrid composition containing a plastisol material that gels up to a temperature rise of 0 ° C and a material that hardens at a temperature of 100 ° C or more.It is useful as a podicealer for automobile body assembly lines, for example. In particular, when using a conventional one-pack type thermosetting polyurethane-based sealer, it is a hybrid type heat seal suitable for automotive sealers and coating materials with the aim of preventing foaming during heat curing after uncured moisture absorption. The present invention relates to a curable material composition, and a method for preventing foaming in a sealing construction in an automobile assembly line, which uses the hybrid thermosetting material composition, and in particular, can prevent moisture absorption and foaming during baking and curing of the composition.

Background art

Sealing in the assembly line of automobiles is performed to maintain airtightness and watertightness when assembling press-formed steel sheets by spot welding such as spot welding, and body sealers are usually applied to joints and gaps. ing.

Conventionally, a PVC plastisol obtained by dispersing a polyvinyl chloride (PVC) powder in a plasticizer has been frequently used as such a podizer, and the PVC plastisol is produced by heating the PVC powder by a heat of 90 to 200 ° C. Absorbs, fuses with each other, solidifies, gels and apparently hardens. Since the main component is PVC, it is easily decomposed by heat, light, etc., and generates hydrogen chloride at the time of decomposition, which is liable to cause corrosion to the base steel sheet.

Therefore, as a substitute for the PVC plastisol, a one-part type thermosetting polyurethane-based sealer is being used, and is usually thermoset at a temperature of 100 ° C. or more. However, in the actual sealing line, the temperature is gradually increased by heating after application of the sealer, but in the uncured state until the curing temperature is reached, the moisture (moisture) in the air is absorbed (moisture absorption). During the temperature rise, for example, foaming starts gradually due to the vaporization of the absorbed moisture from around 70 ° C, and then 100 ° C When the above curing time is reached, foaming is apt to occur rapidly, resulting in failure to maintain the original airtightness and watertightness of the sealer, or a failure of ^ II failure. This foaming situation becomes even more severe when the line is stopped (temporary suspension due to operator breaks or long-term stoppage such as holiday stop or consecutive holidays), because the amount of moisture absorbed accumulates more.

Disclosure of the invention

The present inventors have made intensive studies to solve the problem of foaming of the one-pack type thermosetting polyurethane sealer, and found that a plastisol material containing thermoplastic resin particles, a polyol and an excess of polyisocyanate were used. If a thermosetting material containing a block of a urethane prepolymer containing a terminal isocyanate group obtained by the reaction of the compound is blended with the thermosetting material, a temperature of 60 ° C. to 100 ° C. can be obtained in the heating step of the above line. As a result of the gelation of the plastisol material by the time the temperature rises, foaming due to moisture vaporization can be suppressed, and then, due to the temperature rise of 10 ° C or more, the hardening of the block body advances. It was found that a desired cured cured product in which foaming was prevented was obtained, and the present invention was completed.

That is, the present invention relates to a plastisol material comprising thermoplastic resin particles and a plasticizer, a blocked urethane prepolymer obtained by blocking the free isocyanate group of a urethane prepolymer containing terminal isocyanate groups, and a thermosetting material comprising a curing agent thereof. A hybrid thermosetting material composition characterized by blending the material; and, after applying the hybrid thermosetting material composition, a temperature ranging from 60 ° C. to 100 ° C. It is intended to provide a method for preventing foaming of sealing work in an automobile assembly line, which comprises gelling a plastisol material and then heat-curing the blocked urethane prepolymer by a temperature rise of 100 ° C or more. .

As the thermoplastic resin particles in the present invention, any thermoplastic resin particles may be used as long as they can gel at a temperature of less than 100 ° C. For example, alkyl acrylate (alkyl, methyl, ethyl, butyl, 2-alkyl) MBS resin (MBS resin (MBS resin) Methyl methacrylate / butadiene / styrene); Ionoma Kazuki; AAS resin (acrylonitrile / styrene / special resin) AES resin (acrylonitrile / EP DMZ styrene); AS resin (acrylonitrile / styrene); ABS resin (acrylonitrile / butadiene nostyrene); and resin particles such as polyurethane resin and polyester resin. One or more kinds of resin particles selected from these groups, usually primary particles and secondary particles in which Z or primary particles are aggregated, are used. May be. Particularly, acrylic resin particles are preferable.

As the plasticizer in the present invention, for example, di (2-ethylhexyl) phthalate, ptinolebenzinolephthalate, dinoninolephthalate, diisonoelphthalate, disodesinolephthalate, didecynylphthalate, diheptinolephthalate And phthalic acid esters such as butyrphthalyl butynoleglycolate; aliphatic dibasic acid esters such as octyl adiate, didecyradiate, and dioctyl sebacate; polyoxyethylene glycol benzoyl benzoate, polyoxypropylene Polyglycol benzoic acid esters such as dalicol dibenzoate; Phosphate esters such as tributyl phosphate and tricresyl phosphate; alkyl-substituted diphenyl, alkyl-substituted terfehl, partially hydrogenated alkyl terfehl Examples include hydrocarbons such as aromatic process oils and pine oils.One or a mixture of two or more hydrocarbons selected from these groups may be appropriately selected and used according to the type of the thermoplastic resin particles. I just need. As the plasticizer when acrylic resin particles are used, the above-mentioned phthalic acid esters, particularly diisononyl phthalate, are suitable. The weight ratio between the thermoplastic resin particles and the plasticizer is usually selected to be 100/50 to 50/100.

The blocked urethane prepolymer in the present invention can be produced according to the following procedure.

i) First, a polyol is reacted with an excess of a polyisocyanate compound to obtain a urethane prepolymer containing a terminal isocyanate group (NCO).

Examples of the polyol include polyoxyalkylene polyol (PPG), modified polyether polyol, polyether polyol containing polytetramethylene ether glycol; polyester polyol containing condensation-based polyester polyol, lactone-based polyester polyol, and polycarbonate diol. O And other polybutadiene-based polyols and 7-polyol.

Examples of the polyisocyanate compound include

Tamethylene diisocyanate, 2,4,4- or 2,2,4-trimethinolehexamethylene diisocyanate, dodecamethylene diisocyanate, 1,3-cyclopentane diisocyanate, 1, 6-Hexanediisocyanate (HD I), 1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate, 4,4, -methylenebis (cyclohexynoleisocyanate), 4, 4, -methylenebis (cyclohexyl isocyanate), methyl 2,4-cyclohexyl diisocyanate, methyl 2,6-cyclohexane diisocyanate, 1,4-bis (isosocyanate methyl) Nore) Cyclic hexane, 1,3-bis (isocyanate monomethinole) cyclohexane, m-phenylenedisocyanate, p-phenylenedisocyanate, 4,4, jihue Distearate iso Xia sulfonate, 1, 5-naphthalate range iso Xia sulfonates, 4, 4, over diphenylmethane di iso Xia sulfonate (MD

I), Crude MD I, 2,4-one or 2,6-tolylene diisocyanate, 4,4'-toluidine diisocyanate, dia-zine diisocyanate, 4, 4'-diphenyl ether Examples include diisocyanate, 1,3_ or 1,4-xylylenedithiocyanate, ω, ω, diisocyanate-1,4-tetramethylbenzene.

ii) Next, the urethane prepolymer containing terminal NCO is reacted with an appropriate blocking agent (usually, 0.9 to 1.5 equivalents of the blocking agent are reacted per mole of the former NCO) to give free NCO. To obtain the desired blocked urethane prepolymer.

Examples of the above blocking agents include alcohols such as methanol, ethanol, propanol, ptananol, and isobutanol; phenols such as phenol, cresonole, xylenol, and phenols such as nitrophenol and anorecylphenol; methyl malonate, and ethyl acetate. Active methylene compounds such as acetyl acetone; acid amides such as acetoamide, acrylamide, and acetoyulide; Acid imides such as acid imide and maleic acid imid; imidazoles such as 2-ethylimidazole and 2-ethyl-1-methylimidazole; ratatoms such as 2-pyrrolidone and ε-force prolatatum; acetoxime and methinoleethyl Ketones such as ketoxime, cyclohexanone oxime, and acetanoledoxime; and oximes of anoredaldehyde; and other examples include ethyleneimine and bisulfite.

As the curing agent for the blocked urethane prepolymer in the present invention, a compound having two or more functional groups (such as NH ₂ , NH, and OH) capable of reacting with NCO in the molecule may be used. For example, ethylenediamine Aliphatic polyamines such as diethylenetriamine, hexamethylenediamine, triethylenetetramine and polyoxypropyleneamine; aromatic or alicyclic polyamines such as m-xylylenediamine, hexamethylenetetramine and isophoronediamine Triethanolamine, isopropanolamine, diethanolamine, disopropanolamine, N, N, N ', Ν'-tetra-hydroxyethyl) ethyleneamine, Ν, Ν, Ν,, Ν, -tetra (J3-hydroxypropyl) ethylenediamine, N, N, N, Chechinore) Ethylenediamine, N, N, N,

(—Hydroxypropynole) Ethylenediamine, N, N, di (] 3-Hydroxyethyl) Ethylenediamine, N, N, —di (] 3-Hydroxypropynole) Ethylenediamine, N — (] 3-hydroxy (Tinole) Ethylenediamine, N— (monohydroxypropyl) Ethylenediamine, N, N, N,, Ν,, N "One penta (β-hydroxypropyl) diethylenetriamine, β-hydroxypropyl) diethylenetriamine, Ν, Ν, Ν, mono (/ 3-hydroxypropyl) diethylenetriamine, Ν, N'-di (] 3-hydroxypropyl) diethylenetriamine, Ν— (] 3-hydroxypropyl) diethylene Ditriamine, Ν, Ν, Ν,, Ν,, Ν ", N '"-Hexa (j3-hydroxypropizole) Triethylenetetramine, N, N, ,,, N, -tetra (/ 3-hydroxypropynole) hexamethylenediamine, N, N, di (j3-hydroxypropynole) hexamethylenediamine, N, N, N,, N'-tetra-hydroxy propyl) Single m- xylylene § Min, N, N, temporary (J3- hydroxypropyl Honoré) Single _m - xylene Rirenjiamin, N, N, N ', N, Tetora (3- hydroxypropyl Honoré) iso Polyamine adducts such as holondiamine, N, N, N, and tri () 3-hydroxypropinole) isophoronediamine; adipic dihydrazide, sebacic dihydrazide, isophthalic dihydrazide, 1,3-bis (hydrazinocarboethyl) ) -5-isopropylhydantoin, eicosannilic acid dihydrazide, hydroquinone diglycolic acid dihydrazide, resorcinol diglycolic acid dihydrazide, 4,

Dihydrazide compounds such as 4, ethylidenebisphenoldiglycolic acid dihydrazide; dicyandiamide; 4,4, diaminodiphenylenolesnolephone; imidazole compounds such as imidazole and 2-n-heptanedecylimidazole; Melamine; benzoguanamine; N, N, dialkyl urea compounds; N, N, dialkyl thiourea compounds; Room temperature solid polyamines such as diamine, hexadecanediamine, and hydrazide polyamine; 3,9-bis (3-aminopropyl) -1,2,4,8,10-tetraoxaspiro [5.5] pandecan compound; ethylene Guri Chole, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylonolepropane, 1,4-butanediol, 1,6,1-hexanediol, 1,2,6-hexanetriol, pentaerythritol, diglycerin, etc. And one or a mixture of two or more selected from these groups. The amount used is usually selected so as to be 1.0 to 3.0 equivalents to the NCO of the blocked urethane prepolymer.

The hybrid-type thermosetting material composition according to the present invention comprises a blastisol material comprising the above-mentioned predetermined ratio of thermoplastic resin particles and a plasticizer, and a thermosetting material comprising a blocked urethane prepolymer and its curing agent. The system consists of a mixture of these. In this case, the weight ratio of the thermoplastic resin particles to the blocked urethane prepolymer is usually 20/1 to: L / 20, preferably 15/1 to: LZ2, and more preferably 10/1 to 1/2. Should be selected. If the amount of the thermoplastic resin particles exceeds the above upper limit, the low-temperature flexibility is impaired, and the adhesiveness to the substrate is reduced.If the amount is less than the above lower limit, the gel at a temperature of 100 ° C or lower is used. Is likely to be impaired is there.

If necessary, fillers (kaolin, clay, calcium carbonate (heavy calcium carbonate, precipitated calcium carbonate, surface-treated calcium carbonate, etc.), magnesium carbonate, titanium oxide, calcined stone, barium sulfate, zinc oxide, calcium) Acid, My powder, Asbestos, Tanolek, Bentonite, Silica, Glass powder, Bengala, Car pump, Graphite powder, Alumina, Shirasu balloon, Ceramic balloon, Glass balloon, Plastic vanolane, Metal powder, etc.), moisture absorption Agents (calcium oxide, molecular sieves, etc.), denaturing agents (organic bentonite, fumed silica, anolememi-stearate, metal soaps, castor oil derivatives, etc.), stabilizers [2,6-di-tert-butyl) 4 monomethylphenol, 2, 2- Ren one bis

(4-methyl-1-6-t-butylphenol), dibutyldithiocarbamate, etc.), curing accelerators (dibutyltin dilaurate, otatyl ^ 1, bismuth octoate, etc.), solvents (naphtha, paraffin, etc.) (Boiling point hydrocarbon solvent) and the like may be appropriately selected and added.

In order to use the thus obtained hybrid thermosetting material composition for sealing in an assembly line of an automobile, for example, it is applied to a predetermined joint or gap, and then applied at a temperature of 60 ° C. to 100 ° C. By the temperature rise of ° C, the plastisol material in the composition gels, thickens and hardens. As a result, it is possible to suppress the bubbling caused by moisture abrasion, and if the temperature rises to 100 ° C. or more, free NCO is generated by thermal dissociation of the blocking agent of the blocked urethane prepolymer. In addition to the fact that the curing agent reacts with this and the thermal curing progresses, it can prevent the conventional foaming and can maintain the original airtightness and watertightness as a body sealer, and a good finish It can be a surface.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, the present invention will be described more specifically with reference to examples and comparative examples.

Example 1 and Comparative Examples 1 and 2

(1) Manufacture of blocked urethane prepolymers

Polyether triol (“EL-300” manufactured by Asahi Glass Co., Ltd., molecular weight: 30000) 100 parts (parts by weight, the same applies hereinafter) and MDI 27.8 parts were dibutyltin dilauray. The reaction was carried out at 80 ° C for 5 hours in the presence of 0.0008 parts of a catalyst, to obtain a urethane prepolymer containing NCO at the end, and 6.5 parts of methylethylketoxime was added thereto, and the mixture was added at 50 ° C. 5 hours, and confirm the disappearance of NCO with an infrared spectrometer to obtain a blocked polyurethane prepolymer.

(2) Preparation of body sealer

The components in the parts by weight shown in Table 1 below are kneaded under reduced pressure to obtain a body sealer.

(3) Performance test (Results are also listed in Table 1)

i) When the temperature of the sample from each body sealer was raised from 20 to 120 ° C in 10 minutes with a viscometer (DVE-V4, FT Rheospectral), the gelation start temperature (° C) and G modulus _{^{(d y n / cm 2,}} 70 ° C) to measure (the gelation initiation temperature is read as the temperature at which the viscosity started to rise).

ii) Apply each sample to a thickness of lmm, leave it at 30 ° C and 80% RH for 2 days, bake it at each curing temperature, and visually check the foaming of the cured product at that time.

In Table 1,

Note 1) Zeon Kasei Co., Ltd.

Note 2) PSH180J manufactured by Kanegafuchi Chemical Co., Ltd.

Note 3) "Jeffamine T-403J" manufactured by Daito Sangyo Co., Ltd.

Note 4) "NP400" manufactured by Sanyo Chemical Co., Ltd. Industrial applicability

INDUSTRIAL APPLICABILITY The hybrid thermosetting material composition of the present invention is useful mainly as a foam-free body sealer used in an automobile assembly line. Further, it can be used as a coating material for undercoats of automobiles and other metal materials.

Claims

The scope of the claims

1. a plastisol material comprising thermoplastic resin particles and a plasticizer,

Thermosetting material consisting of a blocked urethane prepolymer in which free isocyanate groups are blocked from urethane prepolymer containing terminal isocyanate groups, and a curing agent thereof

A hybrid thermosetting material composition comprising:

2. The hybrid according to claim 1, wherein the weight ratio of the thermoplastic resin particles to the plasticizer is 100Z50 to 50Z100, and the weight ratio of the thermoplastic resin particles to the blocked urethane prepolymer is 20/1 to 120. -Based thermosetting material composition.

3. After applying a hybrid thermosetting material composition containing the plastisol material described in claim 1 and a thermosetting material, the plastisol material is gelled by a temperature rise from 60 ° C to 100 ° C. A method for preventing foaming in a sealing process on an automobile assembly line, wherein a blocked urethane prepolymer is thermally cured at a temperature rise of at least 100 ° C.