JPH11158368A - Urethane composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a urethane composition that has excellent weatheability and develops high adhesion to glass. SOLUTION: This urethane composition comprises 100 pts.wt. of urethane polymer and 0.1-10 pts.wt. of a compound that contains a kind of radical, at least one member selected from the group consisting of a silane coupling agent as wells as nitroxide radical, aryloxy radical, trityl radical and their derivatives and can stably be present at room temperature in the presence of oxygen.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a urethane composition having excellent weather resistance and exhibiting excellent adhesion to glass.

[0002]

2. Description of the Related Art It is known that a compound containing a radical in a molecule traps a radical generated upon decomposition of a polymer by irradiation of ultraviolet rays or the like and functions as a stabilizer for the polymer. JP-A-61-500123 discloses a thermoplastic polymer using a hindered piperidine compound or a nitroso-containing compound as a stabilizer,
High temperatures and high shear forces are required to generate radicals in these compounds to function as stabilizers. Japanese Patent Application Laid-Open No. 50-58141 discloses a method for stabilizing a synthetic polymer material containing an organic pigment and a fluorescent whitening agent, characterized in that a piperidine derivative and an ultraviolet absorber are used in combination. . However, it has not been known that the adhesiveness is improved by adding a radical.

[0003]

SUMMARY OF THE INVENTION The present invention aims to provide a urethane composition having excellent weather resistance and improved adhesion to glass.

[0004]

Means for Solving the Problems The present inventor has proposed that a compound containing a radical which exists stably at room temperature and in the presence of oxygen in a molecule is added to a urethane composition containing a silane coupling agent in a small amount. The present inventors have found that it is possible to improve the weather resistance and improve the adhesion to glass, and have completed the present invention. That is, the present invention provides a silane coupling agent, a nitroxide radical, a hydrazyl radical, an allyloxyl radical,
A compound containing at least one radical selected from the group consisting of trityl radicals and derivatives thereof in a molecule containing a radical stably present at room temperature and in the presence of oxygen;
There is provided a urethane composition containing 10 parts by weight. Here, the compound containing in its molecule a radical stably present at room temperature and in the presence of oxygen is 2,2,6,6
-Tetramethylpiperidine-1-oxyl and / or a derivative thereof is preferred, and the silane coupling agent is preferably blended in an amount of 0.5 to 10 parts by weight based on 100 parts by weight of the urethane prepolymer. Further, the present invention provides a wind sealant comprising the above urethane composition.

[0005]

DETAILED DESCRIPTION OF THE INVENTION The polyether polyol which is one of the raw materials for producing the urethane prepolymer used in the present invention is, for example, one or more alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide and tetrahydrofuran. Is a compound having a skeleton obtained by addition polymerization of a compound having two or more active hydrogens. Here, as the compound having two or more active hydrogens, for example, polyhydric alcohols such as polyhydric alcohols, amines, alkanolamines, and polyhydric phenols, such as ethylene glycol, propylene glycol, Butanediol, diethylene glycol, glycerin, hexanetriol, trimethylolpropane, pentaerythritol, etc .; amines, such as ethylenediamine, hexamethylenediamine, etc .; Examples of phenols include resorcinol and bisphenol A.

In producing a urethane prepolymer, a polyether polyol having a number average molecular weight of 100
It is preferable to use those having 0 to 7000. Within this range, the glass transition temperature is appropriate and the properties of the cured sealant are excellent.

Examples of the polyisocyanate compound which is the other raw material for producing the urethane prepolymer include various compounds used in the production of ordinary polyurethane resins. Specifically, 2,4-tolylene diisocyanate,
2,6-tolylene diisocyanate, phenylene diisocyanate, xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, naphthalene-
Examples thereof include 1,5-diisocyanate and hydrogenated compounds thereof, and further include ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and triphenylmethane triisocyanate.

[0008] These polyisocyanate compounds can be used alone or in combination of two or more in producing a urethane prepolymer.

In the production of the urethane prepolymer, the amount ratio of the raw materials is such that the equivalent ratio of the isocyanate group (isocyanate group / hydroxyl group) of the polyisocyanate compound to the hydroxyl group of the polyether polyol is 1.1 to 1.1.
It is preferred that the ratio be 2.5. This is because the viscosity of the urethane polymer is appropriate within this range.

The above reaction can be carried out at a reaction temperature of about 50 to 100 ° C. under normal pressure. Also, organotin compounds,
A urethanization catalyst such as an organic bismuth compound can also be used.

Examples of the silane coupling agent used in the present invention include epoxy silane, vinyl silane, amino silane, mercapto silane, phenyl silane and the like. Among them, preferred are aminosilane, mercaptosilane, isocyanatesilane and epoxysilane. The addition amount of the silane coupling agent is 0.1 to 10 parts by weight, preferably 0.5 to 10 parts by weight based on 100 parts by weight of the urethane prepolymer. In the present invention, the silane coupling agent functions as an adhesion-imparting agent. In the present invention, the combination of the silane coupling agent and the compound containing a radical in the molecule provides the urethane composition with excellent adhesion to glass.

The compound containing a radical in the molecule used in the present invention includes a nitroxide radical, a hydrazyl radical,
At least one kind of radical selected from the group consisting of allyloxyl radical, trityl radical and derivatives thereof, and is a compound containing in its molecule a radical that is stably present at room temperature and in the presence of oxygen. Specific examples include the compounds described below. Here, the normal temperature is 80 ° C. or less.

<Nitroxide radical>

[0014]

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[0015]

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(In the above formulas (1) to (6), R is C _1- which may contain O, N, S, P, Cl, Br, I)
A C ₃₀ hydrocarbon group is shown. )

[0017]

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[0018]

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Other examples are as follows.

[0020]

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[0021]

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<Hydrazyl radical>

[0023]

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<Allyloxy radical>

[0025]

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<Trityl radical>

[0027]

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Of these compounds, compounds containing oxygen radicals are preferred, and 2,2,6,6-tetramethylpiperidine-1-oxyl and its derivatives are particularly preferred. This is because oxygen radicals have a high ability to capture carbon radicals generated in the polymer. The compound containing a radical in the molecule used in the present invention is compounded in an amount of 0.1 to 10 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the urethane prepolymer. When the amount is within this range, favorable weather resistance and adhesion to glass can be obtained.

Conventionally, a compound containing a radical in its molecule has been known to have only a stabilizing effect by scavenging radicals generated during decomposition of a polymer as an advantageous effect on a polymer. It has been clarified that it has an effect of improving the adhesion to glass.

The urethane composition of the present invention may further contain, if necessary, a plasticizer, a filler, a catalyst, a thixotropic agent, a solvent, an ultraviolet absorber, a dye, a pigment, a flame retardant and the like.

Examples of the plasticizer include derivatives such as benzoic acid, phthalic acid, trimellitic acid, pyromellitic acid, adipic acid, sebacic acid, fumaric acid, maleic acid, itaconic acid, citric acid, polyester, polyether, and the like. Epoxy-based, paraffin-based, naphthene-based and aromatic-based process oils, and the like. The amount of these components is preferably 30 to 1 with respect to 100 parts by weight of the urethane prepolymer.
00 parts by weight.

Examples of the filler include titanium dioxide, carbon black, silicic acid derivatives, talc, metal powder, calcium carbonate, clay and the like. The amount is preferably 10 to 100 parts by weight based on 100 parts by weight of the urethane prepolymer.
Parts by weight. This facilitates adjustment of viscosity and other physical properties.

Examples of the catalyst include metal catalysts such as dibutyltin dilaurate, dioctyltin laurate, zinc octylate, and organic bismuth compounds, and amine catalysts such as triethylenediamine and morpholine amine. The amount is preferably 0.1 to 3 parts by weight based on 100 parts by weight of the urethane prepolymer. This gives a suitable curing time.

One example of the method for producing the urethane composition of the present invention is as follows. A urethane prepolymer is put into a kneader filled with nitrogen gas, and further, if necessary, a plasticizer and a filler are added. Mix well under reduced pressure. Thereafter, a catalyst may be added and kneaded as needed. The obtained urethane composition can be used as it is, or can be stored in a container after being cooled and sealed after being poured into a container.

Since the present invention is excellent in weather resistance and glass adhesion, it can be suitably used for a wind sealant. The construction site can be suitably used in a location exposed to direct sunlight, wind and rain, and can be suitably used in, for example, an automobile windshield, a housing window glass, and the like.

[0036]

EXAMPLES The present invention will be specifically described below with reference to examples. (Preparation of urethane prepolymer) having three hydroxyl groups,
750 parts by weight of polyoxypropylene triol having an average molecular weight of 5000 and an average molecular weight of 2000 having two hydroxyl groups of 2,000
500 parts by weight of polypropylene ether diol in a reaction vessel, dehydrated under reduced pressure at 110 ° C. and 50 mmHg for 2 hours, cooled to 80 ° C. under normal pressure, 960 parts by weight of dioctyl phthalate, diphenylmethane-4,4′-diisocyanate 214 parts by weight were added and stirred, and reacted at 80 ° C. until the free isocyanate became 1.1% to obtain diphenylmethane-4,4′-diisocyanate (MDI) prepolymer.

(Production of urethane composition) 100 parts by weight of the above urethane prepolymer was put into a kneader container filled with nitrogen, 90 parts by weight of carbon black was added, and the mixture was sufficiently kneaded under reduced pressure. Next, 0.02 parts by weight of a moisture curing catalyst (dioctyltin dilaurate), 1.1 parts by weight of a silane coupling agent (aminosilane), and 1.1 parts by weight of a radical-containing compound (Example 1 and others are described in Table 1) Was added and kneading was performed sufficiently under reduced pressure to obtain a urethane composition. Each of the obtained urethane compositions was used as a wind sealant, and its weather resistance and adhesiveness were evaluated.

[0038]

[Table 1]

The description in Table 1 is as follows. The numerical values in the table indicate% in the evaluation of adhesiveness, and the others indicate parts by weight. Moisture curing catalyst: DOTL (dioctyltin laurate) Silane coupling agent: Y-9669 (manufactured by Nippon Unicar) LA-82: hindered amine compound (Asahi Denka Co., Ltd.)
LA-51: benzophenone compound (Asahi Denka Co., Ltd.)
Neither LA-82 nor LA-51 has a radical in the molecule.

(Evaluation) In the evaluation, a float glass was used as an adherend, and a urethane composition was applied thereon with a thickness of 3 mm.
After standing under the conditions shown in Table 1, a hand peel test was performed to evaluate the rate of cohesive failure (%) of the urethane composition.

[0041]

According to the present invention, there is provided a urethane composition having improved adhesion to glass, excellent weather resistance and excellent adhesion to glass by adding a radical which is stably present at room temperature and in the presence of oxygen. be able to.

Claims (4)

[Claims] A silane coupling agent and at least one radical selected from the group consisting of a nitroxide radical, a hydrazyl radical, an allyloxyl radical, a trityl radical and a derivative thereof are added to 100 parts by weight of a urethane prepolymer at room temperature and oxygen. A urethane composition comprising 0.1 to 10 parts by weight of a compound containing in its molecule a radical stably present in the presence thereof. 2. The compound containing in its molecule a radical stably present at room temperature and in the presence of oxygen is 2,2,6,6-tetramethylpiperidine-1-oxyl and / or a derivative thereof. The urethane composition according to the above. 3. The urethane composition according to claim 1, wherein the silane coupling agent is compounded in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the urethane prepolymer. 4. A wind sealant comprising the urethane composition according to claim 1.