JPH03111448A - One-pack polyurethane composition - Google Patents

Abstract

PURPOSE:To obtain a one-pack polyurethane composition having suitable thixotropy and viscosity and improved storage stability by mixing an NCO- terminated polyurethane prepolymer with colloidal silica and industrial gasolines No.4 and No.5. CONSTITUTION:A polyhydroxyl compound (a) of a weight-average mol.wt. of 100-10000 is reacted with a polyisocyanate compound (b) in an amount to give at most one OH of component (a) per NCO of component (b) at 50-100 deg.C to obtain an NCO-terminated polyurethane prepolymerm 100 pts.wt. said prepolymer is mixed with 0.1-20 pts.wt. colloidal silica and 1-200 pts.wt. industrial gasolines No.4 and No.5 specified in JIS K2201 and optionally a filler, a plasticizer, a tackifier, a curing catalyst, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a one-component polyurethane composition that exhibits appropriate thixotropy and viscosity and has excellent storage stability.

<Prior Art> Polyurethane has excellent elasticity and is therefore widely used as a joint material, a sealant, an adhesive, a covering material, and the like. In such applications, prepolymerized isocyanate compounds (polyurethane) are usually used instead of 1,000 ml to accommodate the conditions at the construction site and to maintain a constant quality of polyurethane after curing. The formulation is designed so that the main component is a prepolymer, which is further hardened and polymerized at the construction site.

Among such polyurethane compositions, a corrugated polyurethane composition is one that is cured by moisture (moisture). Various additives such as fillers such as calcium carbonate, phthalate plasticizers, colloidal silica, aromatic solvents, etc. are also included to make the composition easier to work with (thixotropy, viscosity, etc.). There is.

Among the above additives, colloidal silica is used to impart thixotropy to corrugated polyurethane compositions,
Aromatic solvents are also used to reduce the viscosity of the composition.

<Problems to be Solved by the Invention> As mentioned above, various additives are known for imparting desired physical properties to wave-type polyurethane compositions. These additives are often used in combination, but when the colloidal silica and the aromatic solvent are used in combination, a considerable thickening phenomenon is observed over time, which deteriorates workability.

The present invention has been made in view of the above facts, and is a liquid polyurethane composition containing colloidal silica and a solvent, which exhibits appropriate thixotropy and viscosity and has excellent storage stability. The purpose is to provide a composition.

Means for Solving the Problems The present inventors have completed the present invention as a result of intensive studies on a solvent that does not cause thickening over time for a one-component polyurethane composition containing colloidal silica. be.

That is, the present invention comprises 1 oz of polyurethane prepolymer having an isocyanate group at the end, 0.1 to 20 parts by weight of colloidal silica, and JIS
The present invention provides a liquid type polyurethane composition containing 1 to 200 parts by weight of industrial gasoline No. 4 and/or No. 5 specified by K2201.

The present invention will be explained in detail below.

A polyurethane prepolymer having an isocyanate group at the end is a compound that hardens and polymerizes while forming a urethane bond in the presence of water, and is a reaction product of a polyhydroxyl compound and a polyisocyanate compound. be.

The polyurethane prepolymer having an isocyanate group at the end used in the present invention may be any one generally used in one-component polyurethane compositions, and is not particularly limited.

Examples of the polyhydroxyl compound, which is one of the raw materials for producing polyurethane prepolymers, include various polyether polyols or polyester polyols that are generally used for producing urethane compounds, as well as polymer polyols.

Polyether polyol is a product obtained by addition-polymerizing one or more alkylene oxides such as ethylene oxide, propylene oxide, butylene oxide, and tetrahydrofuran to a compound having two or more active hydrogens. Here, examples of compounds having two or more active hydrogens include polyhydric alcohols, amines, alkanolamines, polyhydric phenols, etc., and examples of polyhydric alcohols include ethylene glycol, propylene glycol, etc. , butanediol, diethylene glycol, glycerin, hexanetriol, trimethylolpropane, pentaerythritol, etc.; amines include ethylenediamine, hexamethylenediamine, etc.; alkanolamines include:
Examples of polyhydric phenols include ethanolamine and propatoolamine, and examples of polyhydric phenols include resorcinol and bisphenols.

In addition, polyester polyols are condensates of polyhydric alcohols and polybasic carboxylic acids, condensates of hydroxycarboxylic acids and polyhydric alcohols, polymers of lactones, etc.
Examples of polyhydric alcohols used in these are the compounds listed above in the section on polyether polyols, and examples of polybasic carboxylic acids include adipic acid, geltaric acid, azelaic acid, fumaric acid, maleic acid, Examples include phthalic acid, terephthalic acid, dimer acid, and pyromellitic acid.

Furthermore, as condensates of hydroxycarboxylic acids and polyhydric alcohols, castor oil, reaction products of castor oil and ethylene glycol, reaction products of castor oil and propylene glycol, etc. are also useful.

In addition, lactone polymers include ε-caprolactam, α
-Methyl-ε-caprolactam, ε-methyl-ε-caprolactam, etc. are ring-opening polymerized using a suitable polymerization initiator.

Polymer polyols include, for example, polyether polyols or polyester polyols graft-polymerized with ethylenically unsaturated compounds such as acrylonitrile, styrene, methyl (meth)acrylate, etc.
, 2- or 1,4-polybutadiene polyol, or hydrogenated products thereof.

Examples of polyhydroxyl compounds that are raw materials for producing polyurethane prepolymers include those listed above, and they may be used alone or in combination of two or more, but the weight average molecular weight io
o to tooo is preferable, and 500 to 500
A value of about 0 is more preferable.

Examples of the polyisocyanate compound which is the other raw material for producing the polyurethane prepolymer include various compounds used in the production of ordinary polyurethane resins. Specifically, 2.4-tolylene diisocyanate, 2.6-
Tolylene diisocyanate, phenylene diisocyanate, xylene diisocyanate, diphenylmethane-4
, 4'-diisocyanate, naphthylene-1,5-diisocyanate, and hydrogenated compounds thereof, ethylene diisocyanate, propylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 1-methyl-2,4-diisocyanate cyclohexane, Examples include 1-methyl-2,6-diisocyanate cyclohexane, dicyclohexylmethane diisocyanate, triphenylmethane triisocyanate, and the like.

These polyisocyanate compounds may be used alone,
Two or more types may be used in combination.

When producing a polyurethane prepolymer having an isocyanate group at the end, the ratio of the polyhydroxyl compound to the polyisocyanate compound is such that the number of hydroxyl groups in the polyhydroxyl compound is 1 or less per 1 isocyanate group in the polyisocyanate compound. Although it is a quantitative ratio,
The number is preferably 0.95 to 0.75.

Moreover, the manufacturing conditions for the polyurethane prepolymer are not particularly limited, and may be the manufacturing conditions for normal polyurethane prepolymers. That is, the reaction may be carried out at a reaction temperature of about 50 to 100°C and under normal pressure.

The colloidal silica used in the present invention is silicic anhydride (silicon dioxide) that is in a colloidal form.

Colloidal silica imparts stability to the corrugated polyurethane composition due to chain structure formation through hydrogen bonding.

Commercially available products include Aerosil #200 (manufactured by Nippon Aerosil Co., Ltd.) and Aerosil R972 (manufactured by Nippon Aerosil Co., Ltd.).
, Cabo-5iL M5 (manufactured by Cabo Co., Ltd.), and the like.

Colloidal silica is 0 parts by weight based on 100 parts by weight of the polyurethane prepolymer having isocyanate groups at the terminals.
．． It is used in an amount of 1 to 20 parts by weight, preferably 0.5 to 12 parts by weight. 0. If it is less than 1 part by weight, it will not be possible to impart stability to the corrugated polyurethane composition, while if it is more than 20 parts by weight, the corrugated polyurethane composition will have a high viscosity and the workability will be extremely poor. .

The industrial gasoline used in the present invention is JIS K2201
These are so-called mineral spirits, which correspond to No. 4 in the classification, and/or so-called cleaning solvents, which correspond to No. 5.

These refined mineral oils, unlike aromatic solvents such as xylene and toluene, lower the viscosity of the one-component polyurethane composition, but even when used in combination with the colloidal silica, they degrade the one-component polyurethane composition over time. difficult to thicken. Incidentally, industrial gasolines No. 1 to No. 3 (according to JIS K2201) have low boiling points and very high volatility, so they are inappropriate for use in the present invention.

In the present invention, industrial gasolines No. 4 and No. 5 may be used alone or in combination, but the total amount is based on 100 parts by weight of the polyurethane prepolymer having isocyanate groups at the terminals. The amount is 1 to 200 parts by weight, preferably 5 to 100 parts by weight. If it is less than 1 part by weight, the effect of reducing the viscosity of the corrugated polyurethane composition will not be achieved, while if it exceeds 200 parts by weight, not only will it be difficult to uniformly disperse the blended system, but the viscosity of the corrugated polyurethane composition will decrease. The viscosity becomes so low that it is difficult to use as an adhesive.

The one-component polyurethane composition of the present invention contains the above-mentioned components, but in addition, within the scope of the spirit of the present invention,
Fillers, plasticizers, tackifiers, curing catalysts, etc. may also be included.

Fillers include calcium carbonate, carbon black,
Clay talc, titanium oxide, quicklime, kaolin, zeolite, diatomaceous earth, vinyl chloride paste resin, glass balloon, vinylidene chloride resin balloon, etc.
Can be used alone or in combination.

As a plasticizer, for example, dioctyl phthalate (DO
P), dibutyl phthalate)-(DBP), dilauryl phthalate (DLP), butylbenzyl phthalate (BB
P), dioctyl adipate (DOA), diisodecyl adipate (DIDA), )-lioctyl phosphate (TOP), tris(chloroethyl) phosphate (T
CEP), tris(dichloropropyl)phosphate (T
DCPP), propylene glycol adipate polyester, butylene glycol adipate polyester, epoxy alkyl stearate, epoxidized soybean oil, etc., which can be used alone or in combination.

Examples of tackifiers include various titanate-based or silane-based coupling agents, reaction products of coupling agents and isocyanate compounds, reaction products of two or more coupling agents (for example, reaction products of various aminosilanes and epoxysilanes). (condensation reaction products of two or more molecules of alkoxy groups of coupling agents), etc., and can be used alone or in combination.

As a curing catalyst, metal catalysts such as dibutyltin dilaurate and lead octylate, and N,N-(dimethylaminoethyl) are used.
- Tertiary amines such as morpholine, etc. can be mentioned.

The method for producing the one-component polyurethane composition of the present invention is not particularly limited, but preferably each component is thoroughly kneaded under reduced pressure and uniformly dispersed to form a composition.

<Examples> The present invention will be specifically described below using Examples, but the present invention is not limited thereto.

(Example 1) Terminal isocyanate group synthesized from polypropylene glycol with an average molecular weight of 3000 (manufactured by Sanyo Chemical Industries, Ltd.), polypropylene triol with an average molecular weight of 5000 (manufactured by Asahi Glass Co., Ltd.), and 4,4'-diphenylmethane diisocyanate (manufactured by MD Kasei Co., Ltd.) 100 parts by weight of 1.4% polyurethane prepolymer, 9.5 parts by weight of colloidal silica (manufactured by Nippon Aerosil Co., Ltd., Aerosil #200), 50 parts by weight of calcium carbonate, 20 parts by weight of titanium oxide, 60 parts by weight of dioctyl phthalate, and industrial 15 parts by weight of gasoline No. 4 (mineral spirit) was uniformly dispersed in a high-viscosity mixer to obtain a corrugated polyurethane sealant composition.

This was placed in a sealed container and left at room temperature, and the viscosity was measured the next day. In addition, the viscosity was similarly measured for those that were left at room temperature for one day and then stored at 70° C. for 24 or 120 hours (accelerated storage stability test).

The results are shown in Table 1.

(Example 2) The same procedure as in Example 1 was carried out except that 15 parts by weight of industrial gasoline No. 5 (cleaning solvent) was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

(Example 3) The same procedure as in Example 1 was carried out except that 12 parts by weight of colloidal silica and 30 parts by weight of industrial gasoline No. 4 were used.

The results are shown in Table 1.

(Example 4) The same procedure as in Example 1 was carried out except that 6 parts by weight of colloidal silica and 12 parts by weight of industrial gasoline No. 4 were used.

The results are shown in Table 1.

(Comparative Example 1) The same procedure as in Example 1 was carried out except that 15 parts by weight of toluene was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

(Comparative Example 2) The same procedure as in Example 1 was carried out except that 15 parts by weight of xylene was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

(Comparative Example 3) The same procedure as in Example 3 was carried out except that 30 parts by weight of toluene was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

(Comparative Example 4) The same procedure as in Example 4 was carried out except that 12 parts by weight of toluene was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

(Example 5) Terminal isocyanate group 9.8 synthesized from polypropylene triol (manufactured by Mitsui Toatsu Chemical Co., Ltd.) with an average molecular weight of 1000 and tolylene diisocyanate (manufactured by Mitsui Toatsu Chemical Co., Ltd.)
% polyurethane prepolymer, 100 parts by weight of colloidal silica (manufactured by Nippon Aerosil Co., Ltd., Aerosil R972)
6 parts by weight, industrial gasoline No. 4 (mineral spirit) 6
0 parts by weight and 0.2 parts by weight of dibutyltin dilaurate were uniformly dispersed in a universal ball mill to obtain a corrugated polyurethane adhesive composition.

Regarding this, the viscosity was measured under the same conditions as in Example 1.

The results are shown in Table 1.

(Comparative Example 5) The same procedure as in Example 5 was carried out except that 60 parts by weight of toluene was used instead of industrial gasoline No. 4.

The results are shown in Table 1.

From Table 1, it is clear that if industrial gasoline No. 4 or No. 5 is used as the viscosity modifier for the corrugated polyurethane composition, the viscosity change of the composition over time is small even when used in combination with colloidal silica. became.

<Effects of the Invention> The present invention provides a one-component polyurethane composition containing colloidal silica and a solvent, which exhibits appropriate stability and viscosity, and has excellent storage stability.

Since the one-component polyurethane composition of the present invention has a small change in viscosity over time, even if it is used after long-term storage, it can provide workability comparable to that of a product immediately after production.

Therefore, it is now possible to impart arbitrary firmness and viscosity to a coating composition, an adhesive composition or a sealant composition made of a corrugated polyurethane composition;
In addition, it becomes possible to extend the shelf life of the product.

Claims (1)

[Claims] (1) 100 parts by weight of a polyurethane prepolymer having an isocyanate group at the end, 0.1 to 20 parts by weight of colloidal silica, and industrial gasoline No. 4 and/or No. 5 1 to 200 specified by JISK2201. A one-component polyurethane composition comprising parts by weight.