KR20170124140A - Preperation method of water-dispersible polyurethane prepolymer and polyurethane coating layer - Google Patents

Abstract

The present invention relates to a method for preparing a polyurethane coating film by preparing CNSL-based polyol which is vegetable oil and synthesizing water-dispersable polyurethane prepolymer using the same. The polyol is manufactured by using diglycidyl ether based on cardanol obtained from CNSL which is vegetable oil. Then, a polyurethane coating film having improved physical properties is prepared by using water-dispersible prepolymer synthesized by using mixed polyol in which the prepared polyol and other diols are mixed at a proper ratio.

Description

TECHNICAL FIELD [0001] The present invention relates to a water-dispersible prepolymer and a polyurethane coating film using a natural vegetable oil-derived polyol,

The present invention relates to a process for producing a urethane-based coating film which improves physical properties by synthesizing polyurethane derived from natural vegetable oil and water-dispersed polyurethane using the same.

The application of the high-efficiency industrial biotechnology concept to the current chemical industry has made it necessary to switch to a green chemical industry that is more environmentally friendly and sustainable growth with less energy consumption. In addition, it is time to take an environmentally friendly polymerization process that uses vegetable oil-based biomass resources as a main raw material to cope with government regulations on volatile organic compounds (VOCs) and replace fossil raw materials.

Cashew Nut Shell Liquid Oil (CNSL) is a liquid (oil) extracted from the shell of Cashew Nut. It is a cheap phenol-based product produced in India, Brazil, Vietnam and Tanzania, Biomass is expected to increase global production to several million tons in the future.

The compounds contained in the CNSL consist of a mixture of various phenolic materials consisting of cardanol, anacardic acid, cardol and 2-methyl cardol, 15 unsaturated substituents having 1 to 3 saturated substituents and double bonds.

The chemical, durability and antifungal properties of linseed oil, palm oil, tung oil, sunflower oil, and soybean oil in the well-known biomass triglyceride structure are poor. On the other hand, CNSL has an aromatic structure and its application is being studied.

The synthesis of polyurethane is carried out by the reaction of a diisocyanate with a polyol and a chain extender, and can exhibit a wide range of properties such as excellent mechanical and physical properties, chemical resistance, and biocompatibility, depending on raw materials used. As a result, it is widely used in many fields such as coatings for paints, plastics, wood and metal materials, paints, adhesives, and waterproofing agents.

As global interest in the environment has increased recently, regulations on the use of organic solvents, which negatively affect human health and the environment, have begun to be regulated. As a solution to this problem, studies on environmentally friendly water-dispersed polyurethane, which is a material that does not pollute the environment and complements the disadvantages of the use of organic solvents, are actively being studied.

Since most of the raw materials used in the manufacture of polyurethane are hydrophobic, the urethane polymer is thermodynamically poorly miscible with water, and the miscibility tends to deteriorate as the molecular weight of the polymer increases. Accordingly, if it is designed to have a cation or an anion in the main chain of the polyurethane, water-dispersed polyurethane that is environmentally friendly can be produced by dispersing in water.

The water-dispersed polyurethane is composed of a soft segment and a hard segment, which are known to exhibit a wide variety of structures and properties by controlling the type and proportion of soft and hard segments. Generally, water-dispersed polyurethane has poor mechanical properties compared with organic solvent-based polyurethane coatings. U-inorganic hybrid material technology is to develop materials that have the advantages of processability, light weight, water resistance, chemical resistance, heat resistance and wear resistance of polymer materials. Recently, it has been applied to many applications by fusion with nanotechnology have.

Korean Registered Patent No. 10-1205322, Nov. 27, 2012 Notice Korean Patent Laid-Open No. 10-2008-0053219, June 12, 2008 Announcement

An object of the present invention is to provide a process for producing a urethane-based coating film which improves physical properties by synthesizing polyurethane derived from natural vegetable oil and water-dispersed polyurethane using the same.

In order to achieve the above object, a method for producing a polyurethane coating film according to an embodiment of the present invention comprises: reacting a polyol containing a compound represented by the following formula (3), an isocyanate compound containing two or more isocyanate groups in a molecule, Preparing a prepolymer by reacting a mixture containing an ionomer compound for introduction to obtain a water dispersible urethane prepolymer having two or more isocyanate groups at the ends of the main chain or side chains; And a coating film forming step of curing the coating liquid containing the prepolymer, neutralizing agent and chain extender to form a polyurethane coating film.

(3)

Wherein R ₁ , R ₂ , R ₃ and R ₄ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms .

The compound represented by Formula 3 may be prepared by reacting a compound represented by Formula 1 below and an amine compound represented by Formula 2-1, Formula 2-2, or both at 40 to 70 ° C for 2 to 6 hours .

[Chemical Formula 1]

[Formula 2-1]

[Formula 2-2]

Wherein R ₁ and R ₂ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, -2, R ₃ and R ₄ are each independently any one selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, The above formula (2-2) is different from each other.

The compound represented by Formula 3 may be any one selected from the following Formulas 3-1, 3-2, 3-3, and combinations thereof.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

The preparation of the prepolymer may be carried out at a reaction temperature of 75 to 95 ° C.

The ionomer and the neutralizing agent may be applied in a molar ratio of 1: 1: 0.5 to 1.5.

The process for producing a water-dispersible urethane prepolymer according to another embodiment of the present invention comprises reacting a polyol containing the compound represented by the above formula (3), an isocyanate compound containing two or more isocyanate groups in the molecule, and an ionomer To obtain a water dispersible urethane prepolymer having two or more isocyanate groups at the ends of the main chain or side chain.

Hereinafter, the present invention will be described in more detail.

As a result of efforts to solve the above-mentioned problems, the inventors of the present invention have found that a CNSL-based polyol having various numbers of -OH groups is produced by reacting an organic compound based on cardanol, which is one of the main components of CNSL, with an alkyl alcohol amine Based polyurethane prepolymer was synthesized by using the polyol thus prepared, and then the polyurethane coating layer was formed using the polyurethane prepolymer.

A process for producing a water-dispersible urethane prepolymer according to an embodiment of the present invention is a process for producing a water-dispersible urethane prepolymer, which comprises reacting a polyol containing a compound represented by the following general formula (3), an isocyanate compound containing two or more isocyanate groups in a molecule and an ionomer compound To obtain a water dispersible urethane prepolymer having two or more isocyanate groups at the ends of the main chain or side chain.

(3)

In Formula 3, R ₁ , R ₂ , R _3, and R ₄ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms.

May be prepared by reacting a compound represented by the following formula (1) and an amine compound represented by the following formula (2-1), (2-2), or both at 40-70 ° C for 2 to 6 hours.

[Chemical Formula 1]

[Formula 2-1]

[Formula 2-2]

Wherein R ₁ and R ₂ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, -2, R ₃ and R ₄ are each independently any one selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, The above formula (2-2) is different from each other.

The compound represented by Formula 1 may be derived from a cardanol component contained in Cashew Nut Shell Liquid Oil (CNSL), which is an alkenyl phenol-based vegetable oil. The cardanol is a compound represented by the following formula (1-1) and has an aromatic structure. It has an advantage that it can be variously functionalized by the presence of an -OH group of a phenol group and an unsaturated alkyl group at a meta position.

[Formula 1-1]

In Formula 1-1, n is 0, 2, 4, or 6.

The compound of Formula 1-1 may be prepared by reacting with epichlorohydrin, which is a compound represented by Formula 1-2.

[Formula 1-2]

The compound represented by Formula 1 may be reacted with any one of amine compounds selected from the group consisting of alkyl amines, dialkyl amines, alkyl alcohol amines, and dialcohol amines to produce the compound of Formula 3.

Specifically, as the amine compound, a compound represented by the above formula (2-1) or (2-2) may be applied, and more specifically, diethanolamine, diethylamine, 2-methylaminoethanol (2-methylaminoethanol), and combinations thereof.

The compound represented by Formula 1 and the amine compound are mixed in a molar ratio of 1: 2 to 2.5, and the reaction is induced at a reaction temperature of 40 to 70 ° C for 2 to 6 hours to synthesize the compound represented by Formula 3 have. Specifically, the reaction temperature may be 55 to 65 ° C. If the reaction temperature is lower than 40 ° C, the synthesis reaction may be slow and productivity may be deteriorated. When the reaction is carried out at a temperature higher than 70 ° C, gelation phenomenon may occur and it may be difficult to ensure sufficient dispersibility. When the reaction temperature is controlled in the range of 55 to 65 ° C, the reaction proceeds more efficiently. In addition, when the amine compound is applied at a molar ratio of less than 2 based on the compound 1 represented by the formula (1), the epoxy group may remain even after completion of the reaction. When the amine compound is used in an amount exceeding 2.5 mole ratio, unnecessary waste Can be.

The compound represented by Formula 3 may be any one selected from the following Formulas 3-1, 3-2, 3-3, and combinations thereof.

[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

The polyol can be applied by mixing a polyol compound (second polyol compound) generally used together with the compound represented by the formula (3) (first polyol compound). Specifically, the second polyol compound is an active hydrogen compound Any molecule having two or more active hydrogen groups selected from the group consisting of a hydroxyl group, a carboxyl group, an amine group, and combinations thereof may be applied.

Specifically, the second polyol compound may be a polyol having a weight average molecular weight of 8,000 or less, and a petroleum-based polyol may be applied. Specifically, examples of the second polyol compound include polypropylene glycol, polyteramethylene glycol, adipate-based polyester polyol, lactone-based polyester polyol, polycarbonate polyol, polybutadiene polyol and acrylic polyol. For example, poly (tetramethylene ether) glycol may be applied to the second polyol compound, but the present invention is not limited thereto.

The compound represented by Formula 3 and the second polyol compound may be used together as a polyol in the following reaction. Specifically, the compound represented by Formula 3 and the second polyol compound may be used in a molar ratio of 1: 2 to 15 And can be applied at a molar ratio of 1: 3 to 10, and can be applied at a molar ratio of 1: 4 to 7. When the content of the compound represented by the general formula (3) is large as compared with the content of the second polyol compound, the scratch resistance and the pencil hardness of the coating film prepared using the same can be improved. Especially, .

In addition, the compound represented by Formula 3 can control the number of hydroxyl groups contained in the molecule as described above. Specifically, the compound having 3 to 6 hydrogens in the compound may have 2 to 8 hydroxy groups, And may have 4, 5 or 6 hydroxy groups. As the number of hydroxyl groups in the compound represented by Formula 3 increases, the scratch resistance, pencil hardness, and solvent resistance of the coated film can be improved.

The isocyanate compound means a compound having at least two -NCO groups capable of reacting with the polyol and the like, and may be a linear or nonlinear isocyanate compound. Specific examples thereof include 4,4-MDI (Methylene diphenyl diisocyanate), HDI diisocyanate, teramethylxylene diisocyanate (TMXDI), 2,4-MDI (methylene diphenyl diisocyanate), TDI (toluene diisocyanate), IPDI (isophorone diisocyanate) and combinations thereof.

The ionomer compound is applied to prepare the prepolymer with water dispersibility. Specifically, polyethylene oxide having a weight average molecular weight of 600 to 1500, polyvinylpyrrolidone having a hydroxy group at the terminal, methyldiethanolamine, ethyldiethanol Amine, propyl diethanol amine, t-butyl diethanol amine, benzyl diethanol amine, 2,2-dimethylol propionic acid, 2,2-dimethylol butanoic acid, 2- Sodium, and combinations thereof may be applied.

When the prepolymer containing the ionomer compound is prepared, an ionic group is introduced into the urethane prepolymer, so that water dispersion can be achieved by self-dispersion of the polymer without addition of an external emulsifier, and uniformity and storage stability of the product can be improved.

The preparation of the prepolymer may be carried out at a reaction temperature of 75 to 95 ° C and may be carried out at a reaction temperature of 80 to 90 ° C.

The compound represented by the above formula (3) can be produced by utilizing a plant-derived oil component and has an aromatic structure, and can be used as a polyol for urethane synthesis by containing two or more hydroxyl groups at the molecular end. The reaction for the preparation of the compound represented by the above formula (3) is relatively simple and easy as described above, and the number of hydroxyl groups in the molecule of the compound represented by the formula (3) can be easily controlled depending on the type of the amine compound So that the utility of the water-dispersed urethane prepolymer and polyol described below is high.

The compound represented by the general formula (3) is reacted with the polyol compound and the isocyanate compound to synthesize a urethane compound having at least two isocyanate groups at the ends of its main chain or side chain and having urethane bonds represented by the following formula (4).

[Chemical Formula 4]

In Formula 4, A ₁ is a moiety excluding the hydroxy group in the compound of Formula 3, and A ₂ is a remaining moiety of the isocyanate compound except for isocyanate groups.

The urethane compound having a urethane bond represented by the formula (4) reacts with the ionomer compound to synthesize a water dispersible urethane prepolymer.

The water-dispersible urethane prepolymer contains a polyol synthesized from a plant-derived oil, and can form a urethane coating film having excellent physical properties as compared with an environmentally friendly but petrochemical-derived polyol. In addition, since ionomeric compounds are introduced to have water-dispersibility, water, which is not an organic solvent, can be applied as a dispersion solvent, which is eco-friendly.

A method for producing a polyurethane coating film according to another embodiment of the present invention comprises reacting a polyol containing a compound represented by the formula (3), an isocyanate compound containing two or more isocyanate groups in a molecule, and an ionomer compound for introducing an ionic group into the molecule To obtain a water dispersible urethane prepolymer having two or more isocyanate groups at the ends of the main chain or side chain; And a coating film forming step of curing the coating liquid containing the prepolymer, neutralizing agent and chain extender to form a polyurethane coating film.

The description of the compound represented by the formula (3) and the polyol, the isocyanate compound, the ionomer compound, the water-dispersible urethane prepolymer, and the process for producing the same will be omitted herein.

The chain extender may be, for example, a low molecular weight diol or a diamine. Specifically, an alkyldiol or an alkyldiamine containing carbon having 2 to 10 carbon atoms (however, the number of carbon is even) may be applied. Specifically, as the chain extender, any one selected from the group consisting of ethylene glycol, propylene glycol, 1,4-butanediol, ethylenediamine, hydrazine, hexamethylenediamine, isophoronediamine, and combinations thereof may be used as a chain extender.

In addition, the neutralizing agent is a material having an ionic group having an opposite tendency to the ionic group of the ionomer, and forms a salt by ionic bonding with the ionic group of the ionomer and further enhances the hydrophilicity. The neutralizing agent may be used in a molar ratio of 0.5 to 1.5 based on the ionomer 1, more specifically in a molar ratio of 0.8 to 1.2. As the neutralizing agent, for example, triethylamine (TEA) may be applied, but the present invention is not limited thereto.

The number of moles of the polyol, the chain extender, and the isocyanate compound may be, for example, 10 to 50 moles of the isocyanate compound based on 10 moles of the polyol, and 1 to 5 moles of the chain extender, And the hydroxyl group or the number of hydroxyl groups and amine groups contained in the chain extender and the number of isocyanate groups of the isocyanate compound.

The reaction can be carried out in a solvent and can be applied without limitation as long as the starting materials of each reaction can be dissolved or dispersed without interfering with the progress of the reaction described above.

The polyurethane thin film produced by the process for producing a polyurethane coating film of the present invention improves the physical properties of the urethane coating film as compared with the case where only the conventional petrochemical polyol is applied and synthesized and applied an aqueous dispersion urethane prepolymer by applying a polyol derived from natural materials It is possible to form a urethane film by an environmentally friendly method.

The water-dispersible prepolymer of the present invention and the method of producing a polyurethane coating film are prepared by preparing a polyol based on CNSL, which is an environmentally friendly vegetable oil, and synthesizing a water-dispersed polyurethane prepolymer by applying the same to the formation of a polyurethane film. It can be applied to various coating fields because it shows improved mechanical properties and film properties compared with water-dispersed polyurethane using diol. In addition, the use of water-dispersed polyurethane reduces the use of toxic organic solvents, which makes it possible to form polyurethane coatings in an environmentally friendly manner as compared with conventional methods.

1 is a graph showing the 1 H-NMR results of the compound represented by Formula 3-1 synthesized in Example 1 of the present invention.
2 is a graph showing FT-IR spectrum measurement results of the compounds represented by Formulas 3-1 to 3-3 synthesized in Examples 1 to 3 of the present invention.
3 is a conceptual view illustrating a process of forming a polyurethane film in Example 8 of the present invention.

Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily carry out the present invention. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the following examples, cardanol-based diglycidyl ether, which is a component derived from cashew nut, NC-514, a compound represented by the following formula (1), is a product of Cardolite, USA Respectively. As the secondary amine, diethanolamine of Junsei purity, diethylamine of Junsei, and 2-methylaminoethanol of Aldrich were applied. As a solvent, xylene of a paleoceanic phase and dimethylacetamide (DMAc) of Aldrich were applied.

[Chemical Formula 1]

PTMG-1000 (TERATHANE® 1000 polyether glycol from Aldrich) was used as a petrochemical-based diol for water-dispersed polyurethane synthesis and was depressurized at 60 ° C for 24 hours before reaction to remove water and the like. Dibutyltin dilaurate (DBTDL) was purchased from Aldrich as a diisocyanate, and Isophorone diisocyanate (IPDI) was purchased from TCI. As an anionic ionomer, Dibutyltin dilaurate (DBTDL) Dimethylol propionic acid (DMPA) was dissolved in DMAc after drying in an oven at 70 ° C. Triethylamine (TEA, Junsei) was used as a neutralizer and 1,4-butanediol (1,4-BD, manufactured by Kanto Chemical Co.) as a chain extender.

The structural analysis of the CNSL-based polyol was confirmed by measuring 1 H-NMR and FT-IR, and the completion of the reaction of water-dispersed polyurethane synthesis was confirmed by FT-IR. FT-IR spectroscopy was performed using a FT-IR spectrum 1000 (Perkin Elmer) with a thin layer of polyol coated on a KRS-5 disc. After scanning 12 times in the range of 4000 ~ 400 cm ^-1 , the results were analyzed and utilized. ¹ H NMR was performed using an AVANCE III 400 MHz instrument and chloroform-d was used as a solvent.

The solvent resistance was determined by measuring the number of times until the coated film was peeled off with isopropanol (IPA) at a constant force, and the hardness of the film was measured according to ASTM D3368. The scratch resistance was measured using a 3090 sclerometer hardness tester.

The solvent resistance was determined by measuring the number of times until the coated film was peeled off with isopropanol (IPA) at a constant force, and the hardness of the film was measured according to ASTM D3368. The scratch resistance was measured using a 3090 sclerometer hardness tester.

To measure the tensile strength, water-dispersed polyurethane was coated on a glass plate to a predetermined thickness. The film was dried thoroughly in a drying oven at 80 ° C and vacuum-dried in a vacuum oven at 60 ° C for one day to prepare a film in which the solvent and moisture were completely removed. The film was produced with a thickness of 0.2 mm, a width of 10 mm, and a length of 50 mm, and tensile strength and elongation were measured at a tensile speed of 200 mm / min. The average value of the remaining data excluding the minimum value and the maximum value among the measured data values was obtained. Tensile strength was measured using UTM.

Comparative Example  One

For the synthesis of water-dispersed polyurethane, a four-necked round bottom flask equipped with a mechanical stirrer, a condenser and a thermometer was placed in an oil bath and the reaction was carried out while maintaining a constant temperature of 85 ° C and a nitrogen atmosphere.

Inside the reactor, a mixed polyol of PTMG-1000, a petrochemical-based diol, isophorone diisocyanate (IPDI), which is a diisocyanate, and an anionic ionomer, dimethylol propionic acid , DMPA) were dissolved in dimethylacetamide (DMAc) as a solvent and charged into the reactor at a molar ratio of 10: 21: 10, respectively, and stirred at 60 RPM.

After the reaction was continued for 6 hours or more, the temperature was lowered to 60 ° C, and then triethylamine (TEA), which is a neutralizing agent, was added dropwise thereto and stirred at 200 RPM for 20 minutes.

When the stirring of triethylamine was completed, a portion of water was dropped first, and the mixture was stirred at 300 RPM for 20 minutes. When the stirring of water was completed, the mixture was stirred at 400 RPM for 20 minutes while dropping a mixed solution containing 1,4-butanediol, which is a chain extender, and water, dropwise. At this time, the neutralizer and the chain extender were added at a molar ratio of 10: 2, and the amount of water was 70 wt% of the whole reaction product.

After all agitation was completed, it was confirmed by FT-IR measurement that the NCO absorption peak completely disappeared and the experiment was terminated.

For the measurement of mechanical properties, water-dispersed polyurethane was coated on a glass substrate to test solvent resistance, pencil hardness, scratch resistance, etc. The results are shown in Tables 1 and 2.

Example  One: CNSL  Based polyol CNSL Synthesis of P-6 (Formula 3-1)

NC-514, a cardanol-based organic compound represented by the formula (1), and diethanolamine, an alkyl alcohol amine, were quantified in a 1: 2 molar ratio and placed in a 500 ml four-neck round bottom flask, , And reacted for 6 hours. When the reaction was completed, the temperature was lowered to room temperature, followed by washing and layer separation to remove unreacted amines and water. The washing was carried out more than 2 times, and when the layer separation was completed, the remaining solvent and water were removed by decompression. When all the steps were completed, a very high viscosity product, CNSL-P-6 (Formula 3-1), was obtained and its structure was determined by measuring 1 H-NMR (shown in FIG. 1) and FT-IR Respectively. It was dissolved in dimethylacetamide for securing fluidity and stored in an oven at 70 ° C. for subsequent experiments.

[Formula 3-1]

Example  2: CNSL  Based polyol CNSL Synthesis of P-4 (Formula 3-2)

The experiment was carried out under the same conditions as in Example 1 except that NC-514, alkyl alcohol amine diethanolamine and diethylamine were used at a molar ratio of 1: 1: 1, respectively. And synthesized CNSL-based polyols, abbreviated as CNSL-P-4. The structure of the synthesized compound is the same as in Example 1 1H-NMR (non-base material) and FT-IR (shown in Fig. 2).

[Formula 3-2]

Example  3: CNSL  Based polyol CNSL Synthesis of -P-3 (Formula 3-3)

Experiments were carried out under the same conditions as in Example 1, except that NC-514, diethylamine, alkyl alcohol amine, and 2-methylaminoethanol were used in a molar ratio of 1: 1: 1, -3 and CNSL-P-3 was abbreviated as CNSL-P-3. The structure of the synthesized compound is the same as in Example 1 1H-NMR (non-base material) and FT-IR (shown in Fig. 2).

[Formula 3-3]

Example  4: Using polyol of formula (3-1) Water dispersion  Polyurethane synthesis

A four-necked round bottom flask equipped with a mechanical stirrer, condenser and thermometer was placed in an oil bath to maintain a constant temperature of 85 ° C and a nitrogen atmosphere. Inside the reactor, a mixed polyol of a CNSL-based polyol CNSL-P-6 and a petrochemical-based diol PTMG-1000, isophorone diisocyanate as a diisocyanate, and an anionic ionomer, Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and charged into the reactor at a molar ratio of 1: 9: 25: 12, respectively, and the mixture was stirred at 60 RPM.

After the reaction was continued for 6 hours or more, the temperature was lowered to 60 ° C, and then triethylamine (TEA), which is a neutralizing agent, was added dropwise thereto and stirred at 200 RPM for 20 minutes. When the stirring of the triethylamine was completed, a portion of water was dropped first, and the mixture was stirred at 300 RPM for 20 minutes. When the stirring of water was completed, the mixture was stirred at 400 RPM for 20 minutes while dropping a mixed solution containing 1,4-butanediol, which is a chain extender, and water, dropwise. At this time, the neutralizer and the chain extender were added in a molar ratio of 12: 2, and the amount of water was set to 70 wt% of the whole reaction product. After all agitation was completed, it was confirmed by FT-IR measurement that the NCO absorption peak completely disappeared and the experiment was terminated. A water-dispersed polyurethane having a final solid content of 25 to 30% by weight was synthesized.

For the measurement of mechanical properties, the water-dispersed polyurethane was coated on a glass substrate to form a coating film and tested for solvent resistance, pencil hardness, scratch resistance, etc. The results are shown in Table 1 below.

Example  5: Using polyol of formula (3-1) Water dispersion  Polyurethane synthesis

A mixed polyol of a CNSL-based polyol CNSL-P-6 (Formula 3-1), a petroleum-based diol PTMG-1000, an isophorone diisocyanate which is a diisocyanate, and an anionic ionomer Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and triethylamine (triethylamine) as a neutralizing agent and 1,4-butanediol (1,4- butanediol were charged into the reactor at a molar ratio of 2: 8: 29: 14: 14: 2, respectively. Experiments were carried out under the same conditions as in Example 4 to form a coating film.

Example  6: Using the polyol of formula (3-2) Water dispersion  Polyurethane synthesis

A mixture polyol of CNSL-based polyol CNSL-P-4 (Formula 3-2), a petroleum-based diol PTMG-1000, an isophorone diisocyanate which is a diisocyanate, and an anionic ionomer Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and triethylamine (triethylamine) as a neutralizing agent and 1,4-butanediol (1,4- butanediol were charged into the reactor at a molar ratio of 1: 9: 23: 11: 11: 2, respectively. Experiments were conducted under the same conditions as in Example 4 to form a coating film.

Example  7: Using polyol of formula (3-2) Water dispersion  Polyurethane synthesis

A mixture polyol of CNSL-based polyol CNSL-P-4 (Formula 3-2), a petroleum-based diol PTMG-1000, an isophorone diisocyanate which is a diisocyanate, and an anionic ionomer Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and triethylamine (triethylamine) as a neutralizing agent and 1,4-butanediol (1,4- butanediol were charged into the reactor at a molar ratio of 2: 8: 25: 12: 12: 2, respectively, and the experiment was conducted under the same conditions as in Example 4 to form a coating film.

Example  8: Using polyol of formula 3-3 Water dispersion  Polyurethane synthesis

Based polyol, CNSL-P-3 (Formula 3-3), a mixed polyol of a petroleum-based diol PTMG-1000, an isophorone diisocyanate as a diisocyanate, and an anionic ionomer for introducing an ionic group Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and triethylamine (triethylamine) as a neutralizing agent and 1,4-butanediol (1,4- butanediol were charged into the reactor at a molar ratio of 1: 9: 22: 10.5: 10.5: 2, respectively, and the coatings were formed under the same conditions as in Example 4, and their physical properties were evaluated.

A description of the reaction proceeded in this case is shown in Fig.

Example  9: Using polyol of formula 3-3 Water dispersion  Polyurethane synthesis

Based polyol, CNSL-P-3 (Formula 3-3), a mixed polyol of a petroleum-based diol PTMG-1000, an isophorone diisocyanate as a diisocyanate, and an anionic ionomer for introducing an ionic group Dimethylol propionic acid (DMPA) was dissolved in dimethylacetamide (DMAc) as a solvent and triethylamine (triethylamine) as a neutralizing agent and 1,4-butanediol (1,4- butanediol were charged into the reactor at a molar ratio of 2: 8: 23: 11: 11: 2, respectively. Experiments were carried out under the same conditions as in Example 4 to form a coating film.

division Applied sample PTMG: Polyol (mole ratio) Scratch resistance
(N) Pencil hardness Solvent resistance
(Number of times) Comparative Example 1 PTMG_PU - 0.5 4H 2 Example 4 CNSL-P-6_PU
(3-1) 9: 1 2.0 8H 10 Example 6 CNSL-P-4_PU
(3-2) 1.2 6H 7 Example 8 CNSL-P-3_PU
(Formula 3-3) 1.3 6H 5 Example 5 CNSL-P-6_PU
(3-1) 8: 2 2.1 8H 27 Example 7 CNSL-P-4_PU
(3-2) 2.0 8H 25 Example 9 CNSL-P-3_PU
(Formula 3-3) 2.0 6H 25

As shown in Table 1, the water-dispersed polyurethane using a mixed polyol obtained by mixing a CNSL-based polyol and a petrochemical-based diol in an appropriate ratio showed an increase in both scratch resistance, pencil hardness and solvent resistance I could confirm.

In other words, referring to Table 1 above, which is a comparison of the scratch resistance, pencil hardness and solvent resistance of each water dispersed polyurethane, it is found that for PTMG_PU, 0.5N scratch resistance, 4H pencil hardness and 2 solvent resistance . When the ratio of PTMG and CNSL - based polyol was 9: 1 (mol), all properties were improved compared to PTMG_PU. This is probably because the CNSL-based polyol participated in the reaction, resulting in a higher degree of crosslinking in the molecule and a higher degree of crosslinking. In addition, when the content of CNSL-based polyol is increased from 9: 1 (mol) to 8: 2 (mol), it exhibits higher physical properties.

division Sample PTMG: Polyol (mole ratio) Strain
(%) Stress
(MPa) Modulus
(MPa) Comparative Example 1 PTMG_PU - 975.0 7.00 0.58 Example 4 CNSL-P-6_PU
(3-1) 9: 1 494.0 10.18 2.02 Example 6 CNSL-P-4_PU
(3-2) 600.0 6.15 0.94 Example 8 CNSL-P-3_PU
(Formula 3-3) 670.4 2.33 0.35 Example 5 CNSL-P-6_PU
(3-1) 8: 2 208.2 12.24 6.09 Example 7 CNSL-P-4_PU
(3-2) 312.0 7.55 3.19 Example 9 CNSL-P-3_PU
(Formula 3-3) 336.0 5.15 2.32

Referring to Table 2, the contents of CNSL-based polyols in Examples 4, 6, and 8 and Examples 5, 7, and 9 are different from each other. As the content of CNSL-based polyol increases, mechanical properties are improved.

This is due to the higher mechanical properties of water-dispersed polyurethane using mixed polyols in which PTMG and CNSL-based polyols are mixed at a proper ratio than when water-dispersed polyurethane was synthesized using only PTMG. Thus, CNSL-based polyols participated in the reaction I think it is because the movement of the molecules is limited as the degree of crosslinking increases and the degree of crosslinking increases.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, Of the right.

Claims (6)

Reacting a polyol containing a compound represented by the following general formula (3) with a mixture containing an isocyanate compound containing two or more isocyanate groups in the molecule and an ionomer compound for introducing an ionic group into the molecule, and reacting at least two isocyanates A step of preparing a prepolymer to obtain a water dispersible urethane prepolymer having a group; And
A coating film forming step of forming a polyurethane coating film by curing a coating liquid containing the prepolymer, the neutralizing agent and the chain extender;
(3)

In the above formula (3)
R ₁ , R ₂ , R ₃ and R ₄ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms. The method according to claim 1,
The compound represented by the general formula (3)
A process for producing a polyurethane coating film, which comprises reacting a compound represented by the following formula (1) and an amine compound represented by the following formula (2-1), (2-2), or both thereof at 40 to 70 ° C for 2 to 6 hours Way;
[Chemical Formula 1]

[Formula 2-1]

[Formula 2-2]

Wherein R ₁ and R ₂ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, -2, R ₃ and R ₄ are each independently any one selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms, The above formula (2-2) is different from each other. The method according to claim 1,
Wherein the compound represented by Formula 3 is any one selected from the group consisting of Formulas 3-1, 3-2, 3-3, and combinations thereof;
[Formula 3-1]

[Formula 3-2]

[Formula 3-3]

The method according to claim 1,
Wherein the step of preparing the prepolymer proceeds at a reaction temperature of 75 to 95 캜. The method according to claim 1,
Wherein the ionomer and the neutralizing agent are applied in a molar ratio of 1: 1: 0.5 to 1.5. Reacting a polyol containing a compound represented by the following general formula (3) with a mixture containing an isocyanate compound containing two or more isocyanate groups in the molecule and an ionomer compound for introducing an ionic group into the molecule, and reacting at least two isocyanates A step of obtaining a water-dispersible urethane prepolymer having a group;
(3)

In the above formula (3)
R ₁ , R ₂ , R ₃ and R ₄ are each independently selected from the group consisting of hydrogen, a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, and a hydroxyalkyl group having 1 to 4 carbon atoms.

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