JP2010275425A - Two-liquid reactive polyurethane resin composition and polyurethane resin obtained by curing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a two-liquid reactive polyurethane resin composition excellent in compatibility and storage stability of a main agent component and to provide a two-liquid reactive polyurethane resin composition giving a polyurethane resin excellent in water resistance and mechanical characteristics. <P>SOLUTION: The two-liquid reactive polyurethane resin composition comprises a main agent (A) and a curing agent (B). The main agent (A) contains a urethane prepolymer obtained by reacting (a) a castor oil polyol, (b) an aromatic monoamine polyol and (c) an organic isocyanate compound selected from a group consisting of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate and their carbodiimide denaturated compounds. The curing agent (B) contains (d) a castor oil polyol, (e) polytetramethylene ether glycol, (f) an amine polyol and (g) a polyamine. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a two-component reactive polyurethane resin composition and a polyurethane resin obtained by curing the two-component reactive polyurethane resin composition. More specifically, the two-component reactive polyurethane resin composition having excellent storage stability, compatibility and water resistance, and The present invention relates to a polyurethane resin obtained by curing this.

  Two-component reactive polyurethane resin can be used widely for spray waterproofing materials, spray flooring materials, cast elastomers, etc., because it can reduce the number of personnel and cost in construction over a wide area by machine coating. Has been.

  Conventionally, in these two-component reactive polyurethane resins, a main component having an isocyanate as a main component and a curing agent component having an amine compound as a main component are used. The resulting polyurethane resin is an isocyanate compound and an amine compound. The main skeleton is a urea bond generated by the reaction of. However, since a large amount of amine compound is used, the curing rate is increased, resulting in a problem that a smooth resin surface cannot be obtained and the resin becomes brittle as the urea bond increases.

  In order to solve this problem, it has been reported that an amine compound and a polyalkylene polyol are used in combination as a curing agent component (Patent Document 1). When the reaction rates of these two component isocyanate compounds are compared, Since the reaction rate of the compound is extremely large, there is a problem that the reaction does not proceed uniformly and it is difficult to obtain a uniform resin.

  In order to solve this problem, it is conceivable to improve the reactivity with isocyanate by blocking addition of ethylene oxide to the terminal of the polyalkylene polyol to form a primary hydroxyl group. The structure comprising this ethylene oxide Has a very high hydrophilicity and tends to reduce the water resistance of the coating film, and when used under submerged conditions, swelling of the resin and peeling from the adherend are problematic.

  Furthermore, it has been reported that high water resistance can be obtained by using a main agent containing a urethane prepolymer composed of a castor oil-based polyol and a polyisocyanate compound and a curing agent component containing a castor oil-based polyol and a polyamine compound. (Patent Document 2). However, since a large amount of the polyamine compound is blended, the reaction tends to proceed non-uniformly and the smoothness of the resin surface tends to be lost. In addition, since the compatibility between the urethane prepolymer and the unreacted polyisocyanate compound is poor, when the average number of hydroxyl groups of the castor oil-based polyol increases, the main agent becomes cloudy due to precipitation of unmodified isocyanate, and storage stability decreases. There was a problem such as.

JP 11-323253 A (Claim 2) JP 2001-181567 A (Claim 2)

  The present invention has been made to solve the above-mentioned problems of conventional two-component reactive spray paints, and the object of the present invention is to provide a main component that is one component of the two-component reactive polyurethane resin composition. An object of the present invention is to provide a two-component reactive polyurethane resin composition having excellent compatibility and storage stability. Another object of the present invention is to provide a two-component reactive polyurethane resin composition that provides a polyurethane resin excellent in water resistance and mechanical properties.

  The two-component reactive urethane composition of the present invention is a two-component reactive polyurethane resin composition comprising a main agent (A) and a curing agent (B), wherein the main agent (A) is (a) a castor oil-based polyol, (B) an aromatic monoamine polyol, and (c) a urethane prepolymer obtained by reacting an organic isocyanate compound selected from the group consisting of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and their modified carbodiimide, and the curing The agent (B) contains (d) castor oil-based polyol, (e) polytetramethylene ether glycol, (f) amine polyol, and (g) polyamine.

  According to the present invention, a two-component reactive polyurethane resin composition excellent in compatibility and storage stability of main ingredient components is provided. In addition, a two-component reactive polyurethane resin composition that provides a polyurethane resin excellent in water resistance and mechanical properties can be provided.

  The two-component reactive polyurethane resin composition of the present invention cures by mixing the main agent (A) and the curing agent (B).

  The main agent (A) in the present invention is selected from the group consisting of (a) castor oil-based polyol, (b) aromatic monoamine polyol, (c) diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and modified carbodiimides thereof. It contains a urethane prepolymer obtained by mixing and reacting with an organic isocyanate compound.

  Here, (a) castor oil-based polyol used for the main agent (A) in the present invention is castor oil, a transesterification product of castor oil and polyol, an esterification reaction product of castor oil fatty acid and polyol, and alkylene A polyol formed by adding an oxide, and the like, is a polyol having a terminal hydroxyl group obtained using castor oil and / or castor oil fatty acid as a raw material. These can be used alone or in combination of two or more.

  (A) The compounding quantity of a castor oil-type polyol is 10-70 weight part with respect to 100 weight part of main agents (A), More preferably, it is 20-50 weight part. (A) When the compounding amount of castor oil-based polyol is less than 10 parts by weight, the storage stability of the main agent tends to be lowered. When (a) castor oil-based polyol is more than 70 parts by weight, the viscosity of the main agent is high. Tend to be.

  Moreover, (b) aromatic monoamine polyol used for the main ingredient (A) in the present invention is obtained by adding an alkylene oxide having 2 to 4 carbon atoms to an aromatic monoamine.

  Examples of the aromatic monoamine include aniline, aniline derivatives having a substituent on the benzene ring, such as a hydrocarbon group and a halogen atom such as fluorine, chlorine, bromine and the like, which do not participate in the urethanization reaction.

  Examples of the alkylene oxide having 2 to 4 carbon atoms include ethylene oxide, propylene oxide, butylene oxide, and the like. Among these, it is more preferable to use propylene oxide or butylene oxide because of excellent water resistance.

  Furthermore, it is preferable that the addition mole number of the said alkylene oxide whose carbon number is 2-4 is 2-10 mol on the average with respect to 1 mol of aromatic monoamines. If it is smaller than this range, the storage stability of the urethane prepolymer tends to be lowered, and if it is larger than this range, the compatibility of the entire main agent (A) is difficult to obtain.

  (B) The compounding quantity of the polyol of an aromatic monoamine is 0.1-10 weight part with respect to 100 weight part of main agents (A), More preferably, it is 0.5-5 weight part. (B) When the compounding quantity of aromatic amine polyol becomes less than 0.1 weight part, the compatibility improvement effect will not fully be acquired and the cloudiness of the main ingredient (A) will occur easily especially at low temperature conditions. Moreover, when the amount of the aromatic amine polyol exceeds 10 parts by weight, the main agent (A) tends to have a high viscosity.

  The (c) organic isocyanate compound used for the main agent (A) in the present invention is diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, or a modified carbodiimide thereof, and one or a mixture of two or more thereof is also ( c) It can be used as an organic isocyanate compound.

  The blending amount of the (c) organic isocyanate compound in the main agent (A) of the present invention is preferably determined so that the NCO / OH equivalent ratio is 2 to 10, more preferably 3 to 7. When the NCO / OH equivalent ratio is less than 2, the viscosity of the main agent (A) tends to be high, and it becomes easy to cause poor mixing. On the other hand, if the NCO / OH equivalent ratio is greater than 10, the proportion of unreacted isocyanate increases, and the main agent (A) tends to become cloudy due to crystallization of the unreacted isocyanate and a decrease in compatibility.

  The viscosity of the main agent (A) in the present invention is preferably 3000 mPa · s or less at 25 ° C. If the viscosity at 25 ° C. exceeds 3000 mPa · s, the pump used for mixing with the curing agent (B) tends to cause cavitation, which is not preferable.

  The main agent (A) in the present invention needs to be free of white turbidity. This is because when white turbidity occurs, problems such as separation of the main component (A) component and poor curing of the polyurethane resin obtained by reacting with the curing agent (B) are likely to occur.

  In the urethane prepolymer contained in the main agent (A) in the present invention, other polyol compounds can be used to the extent that the effects of the present invention are not impaired. Specific examples include polyol compounds used for the production of polyurethane resins, such as polyalkylene polyols, polyester polyols, polytetramethylene ether glycols, polybutadiene polyols, and polycarbonate polyols.

  The curing agent (B) in the present invention contains (d) castor oil-based polyol, (e) polytetramethylene ether glycol, (f) amine polyol, and (g) polyamine.

  As the (d) castor oil-based polyol used for the curing agent (B) in the present invention, as in the case of the main agent (A), any of those conventionally used as a polyurethane resin raw material may be used. A transesterification product of castor oil and polyol, an esterification reaction product of castor oil fatty acid and polyol, and a polyol obtained by adding alkylene oxide to these, and a terminal hydroxyl group obtained using castor oil and / or castor oil fatty acid as a raw material The polyol which has can be mentioned. These can be used alone or in combination of two or more.

  (D) It is preferable that the compounding quantity of a castor oil type polyol is contained in the range of 20-80 weight part in 100 weight part of hardening | curing agents (B), More preferably, it is the range of 40-70 weight part. . (D) When the amount of castor oil-based polyol is less than 20 parts by weight, since the proportion of (e) amine polyol described later increases, reaction non-uniformity is likely to occur, and smoothness of the resin surface is obtained. When the amount is more than 80 parts by weight, the proportion of the (e) amine polyol described below decreases, so that the compatibility between the main agent and the curing agent is reduced, and poor mixing tends to occur.

  The (e) polytetramethylene ether glycol used in the curing agent (B) in the present invention preferably has an average hydroxyl value of 100 to 600 mgKOH / g. When the average hydroxyl value is less than 100 mgKOH / g, the water resistance tends to decrease, and when it exceeds 600 mgKOH / g, mechanical properties such as tensile elongation tend to decrease.

  (E) The blending amount of polytetramethylene ether glycol is preferably contained in the range of 1 to 40 parts by weight, more preferably in the range of 3 to 30 parts by weight, in 100 parts by weight of the curing agent (B). It is. (E) By making the compounding quantity of polytetramethylene ether glycol into the said range, the mechanical strength of a polyurethane resin can be made more favorable.

  The weight ratio of (d) castor oil-based polyol and (e) polytetramethylene ether glycol contained in the curing agent (B) is preferably (d) / (e) = 95/5 to 50/50, It is more preferable that it is 95 / 5-60 / 40. By setting it within the above range, the obtained polyurethane resin has better mechanical properties such as tensile strength and tensile elongation.

  Moreover, as (f) amine polyol used for the hardening | curing agent (B) in this invention, the aromatic amine polyol containing the said (b) aromatic monoamine polyol and an aliphatic amine polyol are mentioned. Examples of the aromatic amine polyol include aniline, toluenediamine, diethyltoluenediamine, 4,4'-diamino-3, 3'-diethyldiphenylmethane and the like to which alkylene oxide is added. Moreover, as aliphatic amine polyol, what added the alkylene oxide to ethylenediamine, hexamethylenediamine, diethylenetriamine, etc. is mentioned. These can be used individually or in mixture of 2 or more types. Of these, aromatic amine polyols are preferred from the viewpoint of improving the water resistance of the polyurethane resin.

  (F) As a compounding quantity of an amine polyol, it is preferable that it is contained in the range of 10-50 weight part in 100 weight part of hardening | curing agents (B), More preferably, it is the range of 15-40 weight part. . (F) When the compounding amount of the amine polyol is less than 10 parts by weight, the effect of improving the compatibility is not sufficient, and when it is more than 50 parts by weight, the viscosity tends to increase, and the resulting polyurethane resin Tends to be hard and brittle.

  Examples of the (g) polyamine used in the curing agent (B) in the present invention include aliphatic polyamines such as ethylenediamine, hexamethylenediamine, and diethylenetriamine, aniline, toluenediamine, 4,4′-diamino-3, 3 ′. -Aromatic amine compounds such as diethyldiphenylmethane and diethyltoluenediamine. Among these, aromatic amines are more preferable from the viewpoint of excellent water resistance and strength.

  (G) It is preferable that the compounding quantity of a polyamine is 0.5-15 weight part in 100 weight part of hardening | curing agents (B). When the amount of the amine compound exceeds 15 parts by weight, the curing time becomes too short, so that the surface smoothness of the resin and the generation of pinholes tend to occur.

  For the curing agent (B) in the present invention, a commonly used metal curing catalyst or amine catalyst of polyurethane resin can be used in order to shorten the curing time. For example, tin catalysts such as dibutyltin dilaurate, dioctyltin dilaurate, dibutyltin dioctate, lead catalysts such as lead octylate, lead octenoate, lead naphthenate, bismuth catalysts such as bismuth octylate and bismuth neodecanoate, triethylenediamine And amine catalysts such as tetramethylhexamethylenediamine.

  The viscosity of the curing agent (B) in the present invention is preferably 3000 mPa · s or less at 25 ° C., similarly to the main agent (A). When the viscosity at 25 ° C. exceeds 3000 mPa · s, the pump used for mixing with the main agent tends to cause cavitation, which is not preferable.

  Moreover, the main agent (A) and the curing agent (B) of the present invention may each contain a plasticizer. Examples of the plasticizer include phthalic acid esters such as dioctyl phthalate and diisononyl phthalate, and adipic acid esters such as dioctyl adipate and diisononyl adipate. By blending the plasticizer, the compatibility of the main agent (A) and the curing agent (B) can be further improved. The compounding amount of the plasticizer is preferably 20 parts by weight or less with respect to 100 parts by weight of the polyurethane resin obtained by reacting the main agent (A) and the curing agent (B) at a predetermined ratio. The following is more preferable. When the amount of the plasticizer is more than 20 parts by weight, the plasticizer tends to bleed out from the obtained polyurethane resin, and the adhesiveness to the top coating material tends to decrease.

  The mixing ratio of the main agent (A) and the curing agent (B) in the two-component reactive polyurethane resin composition of the present invention is preferably such that the NCO / OH ratio is 1.0 to 1.2. When the NCO / OH ratio is less than 1.0, curing failure, water resistance or strength tends to decrease. When the NCO / OH ratio is greater than 1.2, excess isocyanate component is present in the air. It reacts with the moisture of the polyurethane resin, and the polyurethane resin tends to foam.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to these. In the following, “parts” and “%” are “parts by weight” and “% by weight”, respectively, unless otherwise specified.

<(B) Synthesis of aromatic monoamine polyol>
(Synthesis of aromatic monoamine polyol 1)
After 93 g (1 mol) of aniline was added to the autoclave, the inside of the autoclave was replaced with nitrogen. Next, 88 g (2 mol) of ethylene oxide was introduced while maintaining the temperature at 100 ° C. and the pressure of 0.2 MPa, and an aging reaction was performed for 2 hours to obtain an aromatic monoamine polyol 1 (hydroxyl value: 620 mgKOH). / G, viscosity at 25 ° C .: 800 mPa · s).

(Synthesis of aromatic monoamine polyol 2)
After 93 g (1 mol) of aniline was added to the autoclave, the inside of the autoclave was replaced with nitrogen. Next, 116 g (2 mol) of propylene oxide was introduced while maintaining the temperature at 100 ° C. and the pressure of 0.2 MPa, and an aging reaction was performed for 2 hours to obtain amine polyol 2 (hydroxyl value: 535 mgKOH / g). , Viscosity at 50 ° C .: 1300 mPa · s).

(Synthesis of aromatic monoamine polyol 3)
After 93 g (1 mol) of aniline was added to the autoclave, the inside of the autoclave was replaced with nitrogen. Next, 144 g (2 mol) of butylene oxide was introduced while maintaining the temperature at 100 ° C. and the pressure of 0.2 MPa, and an aging reaction was performed for 2 hours to obtain amine polyol 3 (hydroxyl value: 470 mgKOH / g). , Viscosity at 25 ° C .: 2000 mPa · s).

<(F) Method for synthesizing amine polyol>
(Synthesis of amine polyol 1)
After adding 122 g (1 mol) of 2,4-toluenediamine to the autoclave, the inside of the autoclave was replaced with nitrogen. Next, 232 g (4 mol) of propylene oxide was introduced while maintaining the temperature at 100 ° C. and the pressure of 0.2 MPa, and an aging reaction was performed for 2 hours to obtain amine polyol 1 (hydroxyl value: 634 mgKOH / g). , Viscosity at 25 ° C .: 34000 mPa · s).

<Spray coating>
Spray coating using the polyurethane resin composition of the present invention can be performed by a conventionally known method. For example, using a high-pressure two-component collision mixing type spraying device and a spray gun, the liquid temperature of the main agent and the curing agent is 30 to 30. The temperature can be 90 ° C. and the discharge pressure can be 8.2 to 11.2 MPa. Examples of the high-pressure two-component collision mixing type spraying device include H-2000 manufactured by Gasmer. Examples of the spray gun include GX-7 gun manufactured by Gasmer, Probler gun manufactured by Glasscraft, and the like.

<Manufacture of urethane prepolymer>
Table 1 shows the raw materials used for the production of the urethane prepolymer and the curing agent described later.

(Production of urethane prepolymers 1 to 6)
In a flask purged with nitrogen, 26 to 29 parts of castor oil-based polyol shown in Table 2, 1 part to 3 parts of the aromatic monoamine polyol synthesized above, and 51 to 53 parts of isocyanate 1 are mixed at 90 ° C. It was made to react for 1 hour, and after completion | finish of reaction, the urethane prepolymers 1-6 were obtained by mixing the isocyanate 2 (isocyanate 3 regarding the urethane prepolymers 5 and 6) in the ratio of 20 parts. Further, Table 2 also shows the measurement results of NCO / OH ratio, viscosity (mPa · s, 25 ° C.) and storage stability (20 ° C., 24 hours) of each urethane prepolymer 1-6.

  The storage stability of the urethane prepolymer is visually confirmed after storage at 20 ° C. for 24 hours to confirm whether there is turbidity, ○ when there is no turbidity, and x when turbidity or separation is observed. did. In addition, the viscosity measurement is based on JISZ8803, using a rotational viscometer (BROOKFIELD ENGINEERING LABORATORIES, INC., Trade name: B-type viscometer BM) at 25 ° C. It was measured.

<Manufacture of main agent (A)>
As main agents A1 to A6, urethane prepolymers 1 to 6 were respectively used as they were.

<Production of curing agent (B)>
(Production of curing agents B1 to B5)
53 to 70 parts of castor oil-based polyol shown in Table 3, 5 to 20 parts of polytetramethylene ether glycol, 17 to 25 parts of amine polyol, and 2 to 10 parts of polyamine were mixed. Subsequently, with respect to 100 parts of the mixture, 0.4 parts of dioctyltin dilaurate, which is a metal-based curing catalyst, was mixed to obtain curing agents B1 to B5. In addition, Table 3 also shows the measurement results of the viscosity (mPa · s, 25 ° C.) of each of the curing agents B1 to B5. The viscosity of each curing agent was measured under the same conditions as in the case of the main agent (A).

<Manufacture of spray paint and polyurethane resin>
(Examples 1-7, Comparative Examples 1 and 2)
Using the main agent (A) and the curing agent (B) described in Table 4, it was produced by the following method. That is, using a gasmer H-2000 as a high-pressure two-component collision mixing type spraying device, using a gasmer GX-7 gun as a spray gun, the volume ratio of the main agent and the curing agent is 1: 1, and the liquid temperature is 50 ° C. Then, spray coating was performed at a discharge pressure of 8.2 to 10.2 MPa to obtain a polyurethane resin coating film having a thickness of 1 mm.

<Evaluation of polyurethane resin>
Using the coating film obtained by applying the coating method as described above, the surface smoothness, pinhole presence / absence, water resistance, strength, elongation and compatibility were measured by the following methods, and the results were obtained. The results are also shown in Table 4.
(1) Surface smoothness A sample having no irregularities on the surface of the coating film was marked with “◯”, and a sample with irregularities was marked with “x”.
(2) Presence / absence of pinholes The case where no pinholes were observed on the surface of the coating film was marked with ◯, and the case where pinholes were seen was marked with ×.
(3) Water resistance The weight increase rate after the test piece cut out to 20 mm x 40 mm x 1 mm from the said coating film was immersed in 23 degreeC tap water for 3 months was measured.
(4) Tensile strength It measured according to JIS A6021 using the above-mentioned coating film.
(5) Tensile elongation It measured according to JIS A6021 using the said coating film.
(6) Compatibility The main agent and curing agent used in Examples 1 to 7 and Comparative Examples 1 and 2 were heated to 40 ° C. Subsequently, 50 mL of the main agent and 50 mL of the curing agent were stirred in a 200 mL polycup with a homodisper for 3 seconds and then allowed to stand, and the cured polyurethane resin was visually observed. The polyurethane resin was transparent, and the turbidity or poor mixing was evaluated as x.

<Evaluation results>
As is clear from Table 4, all of the polyurethane resins of Examples 1 to 7 using the main agents A1 to A5 and the curing agents B1 to B4 were good results. In particular, the water absorption after immersion in tap water at 23 ° C. for 3 months was 1% or less, and it was revealed that the water resistance was excellent.

  On the other hand, in the polyurethane resin of Comparative Example 1, it can be seen that since the curing agent does not contain an amine polyol, the surface smoothness, pinholes and compatibility are poor, the water absorption is large, and the water resistance is poor. Moreover, since the polyurethane resin of the comparative example 2 does not contain the aromatic monoamine polyol in the main agent, it turns out that compatibility is inferior.

  The two-component reactive urethane composition of the present invention has a low viscosity and can be used in the field of spray paints because it can provide a cured product with high water resistance and excellent mechanical properties such as strength and elongation. It is.

Claims (4)

A two-component reactive polyurethane resin composition comprising a main agent (A) and a curing agent (B),
The main agent (A) is
(A) Castor oil-based polyol,
(B) an aromatic monoamine polyol, and (c) a urethane prepolymer obtained by reacting an organic isocyanate compound selected from the group consisting of diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, and a modified carbodiimide thereof,
The curing agent (B) is
(D) castor oil-based polyol,
(E) polytetramethylene ether glycol,
A two-component reactive polyurethane resin composition comprising (f) an amine polyol, and (g) a polyamine.   2. The composition according to claim 1, wherein (d) castor oil-based polyol and (e) polytetramethylene ether glycol contained in the curing agent (B) are 95/5 to 50/50 by weight. Liquid reaction type polyurethane resin composition.   The two-component reactive polyurethane resin composition according to claim 1 or 2, which is used for spray paint. A polyurethane resin obtained by curing the two-component reactive polyurethane resin composition according to claim 1.