JP3256357B2 - Room temperature curing type polyurethane elastomer composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a room temperature-curable polyurethane elastomer composition having improved defoaming property and a method for improving the defoaming property of a room temperature-curable polyurethane elastomer.
More specifically, a two-part type cold-curing polyurethane elastomer composition with improved defoaming properties, suitable for coating waterproofing materials, coated flooring materials, elastic pavement materials for athletic fields and tennis courts, casting materials, undercoating materials, etc. The present invention relates to a method for improving the defoaming property of a product and a cold-setting polyurethane elastomer.

[0002]

2. Description of the Related Art Polyurethane has a remarkable mechanical strength and is increasingly demanded due to its characteristics such as durability, abrasion resistance, weather resistance, high elasticity and adhesiveness. ing. The room-temperature-curable polyurethane elastomer generally comprises a urethane prepolymer having an isocyanate group at a molecular terminal obtained by reacting tolylene diisocyanate (hereinafter abbreviated as TDI) with a bifunctional and / or trifunctional polyether polyol as a main component. , On the other hand, a curing agent comprising an active hydrogen compound (filler, catalyst, plasticizer,
A pigment, a weather stabilizer, an antifoaming agent, a solvent and the like are blended. ) Are mainly used for the so-called two-pack type polyurethane elastomer used by mixing them during construction. As the active hydrogen compound in the curing agent, 3,3′-dichloro-4,4′-diaminodiphenylmethane (hereinafter referred to as M
Abbreviated as OCA. ) And / or aromatic polyamines (hereinafter referred to as CA) obtained by condensing aniline and 2-chloroaniline with formaldehyde in the presence of a mineral acid.
Abbreviated as -800. ) And polyols such as polyether polyols and polyhydric alcohols.
In addition, since polyamines are solid at room temperature, a method is generally used in which they are dissolved in a polyol.
For applications such as waterproof coating materials and pavement materials, aromatic cured polyamines and polyether polyols are usually used since cured products are required to have flexible and stretchable performance. A urethane prepolymer having an isocyanate group and an active hydrogen compound,
In particular, an organic lead compound is generally used as a urethanization catalyst in the reaction with the polyether polyol, and the curing time is adjusted to suit the application conditions (seasonal) by the amount of the organic lead compound added.

[0003]

In the case of two-component urethane elastomers of ordinary temperature curing type, for example, when a waterproof material, a floor material, a pavement material, etc. are to be applied, two components of a main agent and a curing agent are mixed on site and the mixture is mixed at room temperature. The reaction below forms a rubbery coating. The two components are mixed uniformly using a stirrer, and the mixture is applied so as to have a predetermined film thickness to form a coating film. It is preferable that bubbles entrained at the time of mixing be removed naturally. However, since the foam at the time of mixing cannot be easily removed as it is, it is common to add an antifoaming agent, and usually it is added to the curing agent side. When added to the curing agent, the standard amount requires an antifoaming agent of 0.03 to 0.1% by weight based on the total amount of the polyurethane elastomer composition. By adding an antifoaming agent, bubbles inside are removed, and a clean and smooth surface is obtained without bubbles on the film surface.

However, in the curing agent, polyamine, PPG, plasticizer, catalyst, weather stabilizer,
Pigments are blended, and powders such as calcium carbonate, talc, and talc are added as fillers, so if a defoaming agent is added to the curing agent side, the defoaming agent will be adsorbed on the fillers and other powders. As a result, the defoaming effect was reduced, so that a large amount of defoaming agent had to be added. When applying waterproofing materials, flooring materials, pavement materials, etc., there are few cases where finishing is done with one application, and in general, finishing is done by two or three coatings, but a silicone-based defoaming agent that has a strong defoaming effect on the curing agent Increasing the amount of the foaming agent improves the defoaming effect, but causes bleeding of the silicone on the surface of the coating film after curing. In addition, for example, if dust or dust floating in the air falls on the surface of the coating film after application, there is a problem that a repelling phenomenon occurs and the surface becomes a crater, and when the curing agent is stored for a long period of time, the defoaming effect gradually decreases. There is a problem such as falling, and improvement has been desired.

[0005]

In order to solve the above-mentioned problems, the present inventors have added a small amount of an antifoaming agent of silicone oil to the main ingredient to have a large defoaming effect and a high storage stability. Good, stable defoaming effect even after long-term storage, and does not cause bleeding, even if dust or dust falls on the surface after coating, it does not cause repelling phenomenon, clean and smooth As a result of intensive studies on the method of obtaining the surface, a silicone oil was added to the main component, and 0.002 to 0.03% by weight based on the total amount of the polyurethane elastomer composition.
It has been found that the desired object can be achieved by incorporating the silicone oil of the present invention, and the present invention has been completed.

That is, the present invention is as follows. 1. (1) a main agent mainly composed of a urethane prepolymer having an isocyanate group at a terminal; and (2) aniline in the presence of 3,3′-dichloro-4,4′-diaminodiphenylmethane as a polyamine and / or a mineral acid. An aromatic polyamine obtained by condensing 2-chloroaniline with formaldehyde is used as a polyol, using a divalent or trivalent polyether polyol having an average molecular weight of 75 to 10,000 per active hydrogen as a polyol, and an equivalent ratio of both. Is polyamine / polyol = 10 / 90-90 /
In a polyurethane composition comprising a curing agent whose main component is 10, a silicone oil is added to the main component, and 0.002 to 0.03% by weight of silicone oil is added to the total amount of the polyurethane elastomer composition. A room-temperature-curable polyurethane elastomer composition having improved defoaming properties, characterized by being contained. 2. 1. The silicone oil is dimethylpolysiloxane. The cold-setting polyurethane elastomer composition according to the above. 3. (1) a main agent mainly composed of a urethane prepolymer having an isocyanate group at a terminal; and (2) aniline in the presence of 3,3′-dichloro-4,4′-diaminodiphenylmethane as a polyamine and / or a mineral acid. An aromatic polyamine obtained by condensing 2-chloroaniline with formaldehyde is used as a polyol, using a divalent or trivalent polyether polyol having an average molecular weight of 75 to 10,000 per active hydrogen as a polyol, and an equivalent ratio of both. Is polyamine / polyol = 10 / 90-90 /
10. A method for producing a polyurethane elastomer from a curing agent whose main component is 10, wherein a silicone oil is added to a main component and 0.002 to 0.03% by weight of silicone is added to the total amount of the polyurethane elastomer composition. A method for improving the defoaming property of a room-temperature-curable polyurethane elastomer, characterized by including an oil. 4. 2. the silicone oil is dimethylpolysiloxane; The method for improving the defoaming property of the cold-curable polyurethane elastomer according to the above.

As the raw material organic polyisocyanate for the urethane prepolymer having a terminal isocyanate group used in the present invention, known aromatic, aliphatic and alicyclic polyisocyanates are used. −
Tolylene diisocyanate, 2,6-tolylene diisocyanate and a mixture thereof (hereinafter abbreviated as TDI), particularly those having a weight ratio of 2,4-isomer / 2,6-isomer of 80/20 (hereinafter, TDI) Abbreviated as -80.)
And 65/35 (hereinafter abbreviated as TDI-65) are preferred.

As the polyol, various polyether polyols, polyester polyols, polybutadiene polyols, castor oil, polytetramethylene ether glycol can be used, and propylene oxide or polyoxyalkylene obtained by adding propylene oxide and ethylene oxide to water, propylene glycol or the like can be used. Polyoxyalkylene triol in which propylene oxide or propylene oxide and ethylene oxide are added to glycol, glycerin, trimethylolpropane, or the like is particularly preferable. In addition, low molecular glycols can be used. As the low molecular glycol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-butylene glycol, and 2,3-butylene glycol can be used. These polyols can be used alone or
The polyols are used as a mixture of more than two kinds, and the average molecular weight of the polyol is preferably from 75 to 10,000. The urethane prepolymer can be produced by heating an organic polyisocyanate and a polyol in a nitrogen stream at 80 to 100 ° C. for several hours according to a conventional method.

The curing agent used in the present invention contains MOCA and / or CA-800 as a cross-linking agent as a main component and polyether polyol as a main component. In addition, as a catalyst, an organic lead compound and, if necessary, a filler, a plasticizer, a pigment, Weathering stabilizer,
It contains a solvent and the like. As the crosslinking agent, a liquid amine obtained by dissolving MOCA and / or CA-800 with various polyether polyols having a molecular weight of 400 to 8,000 is used. As the polyether polyol, polyoxyalkylene diol and polyoxyalkylene triol are particularly preferable.

As the catalyst, known urethanization catalysts are used. In particular, organic metal compounds are suitable, and among them, organic lead compounds, for example, lead salts of organic acids such as lead octoate and lead naphthenate are preferably used. . The amount used is preferably 0.1 to 5% by weight based on the total amount of the curing agent.

The filler is preferably, for example, calcium carbonate, talc, clay, carbon black, silicic anhydride (white carbon), zeolite, or titanium dioxide. These fillers can be used alone or in combination. The amount used is preferably from 2 to 50% by weight based on the total amount of the curing agent. As other auxiliaries used in the present invention, all known plasticizers, pigments, weather stabilizers, or, if necessary, solvents and the like can be used.

Examples of the plasticizer include dioctyl phthalate (DOP), dibutyl phthalate (DBP), dioctyl adipate (DOA), and tricresyl phosphate (TC).
P), chlorinated paraffin, U-Rex (alicyclic polymer-modified natural resin ester, manufactured by Tokyo Resin Industry Co., Ltd.) and the like.
Examples of pigments include chromium oxide, inorganic pigments such as red iron oxide,
Organic pigments such as phthalocyanine pigments and azo pigments are exemplified. Examples of the weather stabilizer include Nocrack 300 (trade name).
And Nocrack NS-6 (produced by Ouchi Shinko Chemical Co., Ltd.), trade names Irganox 1010 and 1076 (produced by Ciba Geigy), trade names Yoshinox BHT, BB and GSY-9
Positionally hindered phenols such as 30 (manufactured by Yoshitomi Pharmaceutical Co.)
Benzotriazoles such as Tinuvin P, 327 and 328 (manufactured by Ciba Geigy), benzophenones such as Tomisorb 800 (manufactured by Yoshitomi Pharmaceutical Co., Ltd.), and Sanol LS-770
And 744 (manufactured by Sankyo) and Tinuvin 144 (manufactured by Ciba-Geigy). Examples of the solvent include aromatic hydrocarbons such as toluene and xylene, hexane, cyclohexane, aliphatic hydrocarbons such as Isopar H and M (manufactured by Exxon), esters such as ethyl acetate, and ketones such as methyl ethyl ketone. Is mentioned.

The silicone oil used in the present invention includes dimethylpolysiloxane, methylphenylpolysiloxane, methylvinylpolysiloxane and the like, with dimethylpolysiloxane being particularly preferred. As dimethylpolysiloxane, the viscosity varies depending on the degree of polymerization.
~ 1000 centistokes is preferred. Dimethylpolysiloxane is added to the main component, and its content is 0.002 to the total amount of the polyurethane elastomer composition.
~ 0.03% by weight is preferred. If the content is 0.03% by weight or more, silicone bleeds and repelling phenomenon is caused, which is not preferable.

The cold-setting polyurethane elastomer composition according to the present invention can be applied by a conventional coating method such as a coating film waterproofing material, an elastic pavement material, a flooring material, and a primer material. At this time, the equivalent of the NCO group and active hydrogen in the prepolymer is 0.9 to 1.4, particularly preferably 1.05 to 1.5.
The amount of each component is determined so as to be 1.10.

The defoaming property was evaluated by, after curing, cutting the inside of the film with a cutter and visually observing the presence or absence of bubbles on the cross section, and visually observing the presence or absence of bubbles on the surface of the surface. As a method for evaluating storage stability, a curing test was performed using a main agent or a curing agent one year after the production, and the presence or absence of air bubbles inside the film and on the surface after curing was observed. The method of evaluating the surface bleed after application was determined by curing the silicone at room temperature for one week after application and then visually observing and touching the surface with the silicone to determine whether or not silicone had bleeded. The method for evaluating the surface finish was as follows. The next day after coating, dust was dropped on the surface, and the presence or absence of a repelling phenomenon on the surface and the presence or absence of a crater due to repelling were visually observed.

[0016]

The present invention will be specifically described below with reference to examples. Parts in the examples represent parts by weight. First, a urethane prepolymer used as a main ingredient was produced. Production of urethane prepolymer (A) Polyoxypropylene diol 4 having an average molecular weight of 2000
After uniformly mixing 00 parts, 400 parts of polyoxypropylene triol having an average molecular weight of 4000 and 124 parts of TDI-80, the mixture was mixed at 80 ° C. for 2 hours in a nitrogen stream, and then 10 parts.
The reaction was performed at 0 ° C. for 2 hours. NCO group content 3.1% by weight,
A urethane prepolymer (A) having a viscosity of 10,000 cps / 25 ° C. was obtained. Production of urethane prepolymer (B) Polyoxypropylene diol 14 having an average molecular weight of 400
0 parts, 90.0 parts of polyoxypropylene diol having an average molecular weight of 2,000, 480 parts of polyoxypropylene triol having an average molecular weight of 3,000, 60 parts of DOA, TDI-8
0 After uniformly mixing 240 parts, 80 parts were mixed in a nitrogen stream.
The reaction was carried out at 2 ° C. for 2 hours and then at 100 ° C. for 2 hours. NCO
Group content 6.0% by weight, viscosity 8,000 cps / 25
C. A urethane prepolymer (B) was obtained.

Example 1 7.5 parts of MOCA, 7.4 parts of polyoxypropylene diol having an average molecular weight of 3000, 7.4 parts of polyoxypropylene triol having an average molecular weight of 5,000, and 20.5 parts of DOP
Parts, calcium carbonate 50.0 parts, catalytic lead octylate (p
(b content 25%), 1.2 parts of Nocrack 300 (manufactured by Ouchi Shinko Chemical Co., Ltd.) and 5.0 parts of toner are added, and the mixture is uniformly kneaded with a dissolver to obtain a curing agent for a coating film waterproofing material. (A) was obtained. The curing agent (A) and the urethane prepolymer (A) added with 0.02% by weight of dimethylpolysiloxane (trade name: L-45, viscosity: 1000 centistokes, manufactured by Nippon Unicar Co., Ltd.) at a weight ratio of 1/1 After uniformly mixing using a 3-blade stirrer at a ratio, the mixture was flowed on a concrete substrate, and then uniformly applied to a thickness of 2 mm using a metal iron to form a waterproof material layer. The waterproof layer film was cut with a cutter, and the internal cross section and the surface were visually observed. In each case, no air bubbles were observed and the finished state was smooth and smooth. Further, the surface after the application was good without any bleeding or repelling phenomenon. The storage stability was also good.

Example 2 In Example 1, L-45 was increased to 0.04% by weight,
Others were the same. The waterproof layer film was cut with a cutter, and the internal cross section and the surface were visually observed. In each case, no air bubbles were observed and the finished state was smooth and smooth. Further, the surface after the application was good without any bleeding or repelling phenomenon. The storage stability was also good.

Example 3 15.0 parts of MOCA, 24.0 parts of polyoxypropylene diol having an average molecular weight of 3000, 17.8 parts of DOP, 37.2 parts of calcium carbonate, 0.5% of lead octylate (pb content: 25%) Parts, 0.5 parts of Irganox 1035 (manufactured by Ciba Geigy) and 5.0 parts of toner were added and uniformly kneaded with a dissolver to obtain a curing agent (B) for flooring. The curing agent (B) and the base urethane prepolymer (B) to which 0.005% by weight of a dimethylpolysiloxane (trade name: L-45, viscosity: 1000 centistokes, manufactured by Nippon Unicar Co., Ltd.) were added were added in a weight ratio of 1 / After the mixture was uniformly mixed at a ratio of 1 using a three-blade stirrer, the mixture was flowed on a concrete base, and then uniformly applied to a thickness of 2 mm using a metal iron to form a floor. The waterproof layer film was cut with a cutter, and the internal cross section and the surface were visually observed. In each case, no air bubbles were observed and the finished state was smooth and smooth. Further, the surface after the application was good without any bleeding or repelling phenomenon. The storage stability was also good.

Comparative Example 1 The procedure of Example 1 was repeated except that 0.02% by weight of L-45 was added to the curing agent (A). The cured waterproof layer film was cut with a cutter, and the internal cross section and surface were visually observed. Small bubbles were observed inside and on the surface, and the finished state was poor. Further, in the storage stability test, many air bubbles were observed both inside and on the surface of the cured product, and the finished state was poor.

Comparative Example 2 The procedure of Example 2 was repeated except that 0.04% by weight of L-45 was added to the curing agent (A). The cured waterproof layer film was cut with a cutter, and the internal cross section and surface were visually observed. Small bubbles were observed inside and on the surface, and the finished state was poor. Further, in the storage stability test, many air bubbles were observed both inside and on the surface of the cured product, and the finished state was poor.

Comparative Example 3 In Example 3, 0.005 L-45 was added to the curing agent (B).
% By weight, and the other steps were the same. The cured waterproof layer film was cut with a cutter, and the internal cross section and surface were visually observed. Small bubbles were observed inside and on the surface, and the finished state was poor. Further, in the storage stability test, many air bubbles were observed both inside and on the surface of the cured product, and the finished state was poor.

Comparative Example 4 The procedure of Example 3 was repeated except that the amount of L-45 added to the curing agent (B) was increased to 0.1% by weight. The cured waterproof layer film was cut with a cutter, and the internal cross section and surface were visually observed. As a result, no air bubbles were observed on the inside and on the surface, and the film was in a clean and smooth finished state. However, silicone bleed was observed on the surface of the first layer, and craters due to repelling occurred on the entire surface, resulting in a poor finish. The storage stability was good. Tables 1 and 2 summarize the above results.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

EFFECT OF THE INVENTION According to the present invention, the defoaming property is good, the storage stability is also good, the defoaming effect is stable even after long-term storage, and it is beautiful without causing bleeding or cissing on the coating film surface. And a smooth surface can be obtained.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-261313 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 18/00-18/87 C08L 75 / 00-75/12

Claims (4)

(57) [Claims] 1. A (1) main ingredient mainly composed of a urethane prepolymer having an isocyanate group at a terminal, and (2) a 3,3′-dichloro-4,4′-diaminodiphenylmethane and / or a mineral acid as a polyamine. An aromatic polyamine obtained by condensing aniline and 2-chloroaniline with formaldehyde in the presence is converted into a polyol having an average molecular weight of 75 to 1000 per active hydrogen.
0 divalent or trivalent polyether polyol, and the equivalent ratio of both is polyamine / polyol = 10/9
In a polyurethane composition comprising a curing agent whose main component is 0 to 90/10, a silicone oil is added to the main component, and 0.002 to 0.03% by weight based on the total amount of the polyurethane elastomer composition A cold-curable polyurethane elastomer composition having improved defoaming properties, characterized by containing a silicone oil of the formula (1). 2. The cold-setting polyurethane elastomer composition according to claim 1, wherein the silicone oil is dimethylpolysiloxane. 3. A (1) main ingredient mainly composed of a urethane prepolymer having an isocyanate group at a terminal, and (2) a 3,3′-dichloro-4,4′-diaminodiphenylmethane and / or a mineral acid as a polyamine. An aromatic polyamine obtained by condensing aniline and 2-chloroaniline with formaldehyde in the presence is converted into a polyol having an average molecular weight of 75 to 1000 per active hydrogen.
0 divalent or trivalent polyether polyol, and the equivalent ratio of both is polyamine / polyol = 10/9
In a method for producing a polyurethane elastomer from a curing agent containing 0 to 90/10 as a main component, a silicone oil is added to a main component, and 0.002 to 0.03 to a total amount of the polyurethane elastomer composition. What is claimed is: 1. A method for improving the defoaming property of a cold-curable polyurethane elastomer, characterized by containing silicone oil in an amount of at least 1% by weight. 4. The method according to claim 3, wherein the silicone oil is dimethylpolysiloxane.