JP6129681B2 - Polycarbonate diol, thermoplastic polyurethane, coating composition and coating film - Google Patents

Description

  The present invention relates to a polycarbonate diol, a thermoplastic polyurethane, a coating composition and a coating film.

  Polycarbonate diol is known as a material excellent in hydrolysis resistance, light resistance, oxidation degradation resistance, heat resistance and the like as a soft segment such as polyurethane and thermoplastic elastomer. However, since polycarbonate diol using 1,6-hexanediol as the main raw material exists in a solid state at room temperature due to its high crystallinity, a large amount of solvent is required when it is used as a paint or when polyurethane is produced by polymerization. There was an inconvenience that the handling was hindered.

  In order to solve such an inconvenience, various liquid polycarbonate diols have been proposed. For example, a polycarbonate diol that is liquid at room temperature, in which the diol component is composed of 1,6-hexanediol and 1,4-cyclohexanedimethanol has been proposed (see, for example, Patent Document 1). Further, a polycarbonate diol obtained by using 3-methyl-1,5-pentanediol as a main glycol raw material has been proposed (see, for example, Patent Document 2). Furthermore, a polycarbonate diol composed of repeating units derived from 1,6-hexanediol and 1,5-pentanediol has been proposed (see, for example, Patent Documents 3 and 4).

JP 2011-84751 A International Publication No. 2007/108198 Pamphlet JP-A-2-289616 International Publication No. 2009/63768 pamphlet

  However, in the techniques described in Patent Documents 1 to 4, a polycarbonate diol that is easy to handle due to low crystallinity and is liquid at room temperature, and further can obtain a polyurethane having toughness and chemical resistance. Can't get. That is, when used as a constituent component of a paint, it is possible to obtain a polycarbonate diol that is excellent in handleability and exhibits good compatibility with a curing agent, and further can obtain a tough and chemical-resistant coating film. Can not.

  The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to exhibit excellent compatibility with a curing agent as well as excellent handleability, and toughness and excellent chemical resistance. An object of the present invention is to provide a polycarbonate diol capable of providing a coating film excellent in abrasion resistance, chemical resistance and transparency as a polyurethane or a coating composition. Moreover, the objective of this invention is providing the coating film obtained from the thermoplastic polyurethane obtained from the above polycarbonate diol, the coating composition containing the said polycarbonate diol, and the said coating composition.

That is, the configuration of the present invention is as follows.
[1]
A polycarbonate diol having a repeating unit represented by the following formula (A) and a terminal hydroxyl group, wherein at least a part of the repeating unit represented by the formula (A) comprises the following formulas (B), (C) and ( D) is a repeating unit represented by formula (B), (C), and (D), and the total number of repeating units represented by formula (A) is 80 to 100 mol% of the repeating unit represented by formula (A). Yes, the repeating unit represented by the formula (B) is 18 to 40 mol% based on the sum of the repeating units represented by the formulas (B), (C) and (D), and the formulas (C) and ( A polycarbonate diol characterized in that the ratio of the repeating unit represented by D) is 40:60 to 85:15 in molar ratio.
[2]
The polycarbonate diol according to the above [1], which is liquid when heated to 80 ° C. and then cooled to room temperature.
[3]
A thermoplastic polyurethane obtained from the polycarbonate diol according to the above [1] or [2] and an organic polyisocyanate.
[4]
A coating composition comprising the polycarbonate diol according to the above [1] or [2] and an organic polyisocyanate.
[5]
A coating film obtained from the coating composition according to the above [4].

  The polycarbonate diol of the present invention is excellent in handleability and can exhibit good compatibility with a curing agent. In addition, the thermoplastic polyurethane of the present invention exhibits toughness and excellent chemical resistance. In addition to toughness, the coating composition of the present invention and the coating film obtained therefrom exhibit excellent wear resistance, chemical resistance and transparency.

  Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as “the present embodiment”) will be described in detail. The following embodiment is an exemplification of the present invention, and the present invention is not limited to the following contents. And this invention can be deform | transformed suitably and implemented within the range of the summary.

  The polycarbonate diol of this embodiment has a repeating unit represented by the following formula (A) and a terminal hydroxyl group.

  In the polycarbonate diol of the present embodiment, at least a part of the repeating unit represented by the formula (A) is a repeating unit represented by the following formulas (B), (C) and (D),

  The total of the repeating units represented by the above formulas (B), (C), and (D) is 80 mol% or more and 100 mol% or less of the repeating units represented by the formula (A). Since the total proportion of the repeating units represented by the formulas (B), (C), and (D) in the repeating unit represented by the formula (A) is adjusted to the above range, the polycarbonate diol of this embodiment is , Handling becomes good. From the viewpoint of enhancing the above effects, the above range is preferably 90 mol% or more and 100 mol% or less.

  In the polycarbonate diol of the present embodiment, the repeating unit represented by the formula (B) is 18 mol% or more with respect to the total repeating units represented by the formulas (B), (C), and (D). The ratio of the repeating units represented by the formulas (C) and (D) is 40:60 to 85:15 in terms of molar ratio. The ratio of the repeating unit represented by the formula (B) to the sum of the repeating units represented by the formulas (B), (C) and (D), and the repeating units represented by the formulas (C) and (D) Since the ratio is adjusted to the above range, the polycarbonate diol of this embodiment is a coating film that exhibits excellent compatibility with the curing agent and also exhibits excellent transparency, chemical resistance, and abrasion resistance. In addition, the polyurethane can exhibit excellent toughness and chemical resistance.

  Since the polycarbonate diol of the present embodiment is adjusted so as to satisfy all of the above desired ranges, the handleability is excellent and the compatibility with the curing agent is exhibited, and further, excellent transparency and resistance. It can be a coating film that exhibits chemical resistance and abrasion resistance, and can be a polyurethane that exhibits excellent toughness and chemical resistance.

  In addition, the repeating unit represented by Formula (B) is 20 mol% or more and 35 mol% or less with respect to the total of the repeating units represented by Formula (B), (C), and (D), and / or The ratio of the repeating units represented by the formulas (C) and (D) is preferably 50:50 to 85:15 in terms of molar ratio. In the above case, the toughness of the resulting polyurethane can be further improved, and the wear resistance, chemical resistance and transparency of the coating film tend to be further improved.

  In the polycarbonate diol of the present embodiment, the ratio of the repeating unit represented by the formula (A) is preferably 95 mol% or more from the viewpoint of further improving the performance such as heat resistance and hydrolysis resistance of the polycarbonate diol. It is 100 mol% or less, More preferably, it is 97 mol% or more and 100 mol% or less, More preferably, it is 99 mol% or more and 100 mol% or less.

  The copolycarbonate diol in the present embodiment is preferably in a liquid state at room temperature after being left in an manufactured state or in an atmosphere of ambient conditions from the viewpoint of ensuring better handling. “Liquid” in the present embodiment means a transparent and fluid state. In other words, after being heated to 80 ° C. and then cooled to room temperature, when viewed from the front of the transparent container, it is in a state where the scenery behind can be visually recognized, and even when the transparent container is tilted, even a slight flow It means a state showing gender. In addition, the term “liquid at normal temperature” in the present embodiment means that it is liquid at any temperature within a temperature range of 15 ° C. to 30 ° C., for example. It is preferably liquid at 10 ° C. or higher, more preferably liquid at 5 ° C. or higher.

  Moreover, the polycarbonate diol of this embodiment can also contain the structure represented by the repeating unit of a following formula (E) in the molecule | numerator in order to provide the more outstanding softness | flexibility.

  The method for introducing the repeating unit of the above formula (E) into the polycarbonate diol molecule in the present embodiment is not particularly limited. For example, polyoxyethylene glycol, polyoxyethylene propylene glycol, polyoxyethylene tetramethylene glycol Further, an ether-based polyol such as polyoxytetramethylene glycol or polyoxypropylene glycol may be added to the raw material diol, or an alkylene oxide such as ethylene oxide and / or propylene oxide may be added during the polymerization.

  In the polycarbonate diol of this embodiment, the content of the repeating unit of the formula (E) in the molecule is not particularly limited as long as it does not affect the effect of this embodiment. From the viewpoint of ensuring better heat resistance and chemical resistance in the polyurethane obtained from the polycarbonate diol, it is preferable to adjust the content so as not to increase excessively. That is, when the repeating unit represented by the formula (E) is introduced into the polycarbonate diol of the present embodiment, the repeating unit of the carbonate represented by the formula (A) is represented by the formula (E) ( The repeating unit (having a structure derived from ether) is preferably 0.05 mol% or more and 5 mol% or less, and more preferably 0.05 to 3 mol%.

  The number average molecular weight of the polycarbonate diol of this embodiment is preferably 300 or more and 5000 or less. If the number average molecular weight is 300 or more, the low temperature characteristics of the resulting polyurethane tend to be better. In addition, when the number average molecular weight is 5000 or less, when used as a constituent material of a paint, restrictions such as a paint solid content concentration are relaxed, and a decrease in molding processability of the resulting polyurethane can be effectively prevented. is there. From the same viewpoint, the number average molecular weight is more preferably 450 or more and 3000 or less. In addition, in this embodiment, the said number average molecular weight can be specified by the method as described in the Example mentioned later.

  The method for producing the polycarbonate diol used in the present embodiment is not particularly limited. For example, it can be produced by various methods described in Schnell, Polymer Reviews Vol. 9, p9-20 (1994).

  As the polycarbonate diol of this embodiment, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol can be used as a diol raw material. Usually, the above three kinds of diols can be mixed to obtain a diol raw material. A diol mixture obtained by hydrogenating a dibasic acid mixture containing succinic acid, glutaric acid, and adipic acid can also be used as a raw material without being separated into diols such as 1,4-butanediol. In that case, a specific diol can be additionally used according to the repeating unit composition of the polycarbonate diol.

  In addition to the above three diols, ethylene glycol, 1,3-propanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol, 1,10-dodecanediol, 1,11- Diols having no side chain such as undecanediol, 1,12-dodecanediol, 2-methyl-1,8-octanediol, 2-ethyl-1,6-hexanediol, 2-methyl-1,3-propanediol 3-methyl-1,5-pentanediol, 2,4-dimethyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3- Diols having side chains such as propanediol, 2,2-dimethyl-1,3-propanediol, 1,4-cyclohexanedimethanol, 2-bis 4-hydroxycyclohexyl) - cyclic diols such as propane, may be used one or more kinds of diol as a raw material. The amount of these diols is not particularly limited, but for example, 0.1 mol relative to the total number of 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol used. % Or more and 10 mol% or less is preferable. By satisfying the above range, the polycarbonate diol of the present embodiment tends to be a polyurethane having excellent toughness and chemical resistance. From the same viewpoint, it is more preferable that the above range satisfies 0.1 mol% or more and 5 mol% or less.

  Furthermore, a compound having three or more hydroxyl groups per molecule, for example, trimethylolethane, trimethylolpropane, hexanetriol, pentaerythritol, etc. can be used within a range not impairing the performance of the polycarbonate diol of the present embodiment. From the viewpoint of effectively preventing gelation due to crosslinking during the polymerization reaction of the polycarbonate, it is preferable to adjust the amount of the compound having three or more hydroxyl groups in one molecule. That is, when a compound having three or more hydroxyl groups in one molecule is used, the compound is based on the total number of moles of 1,4-butanediol, 1,5-pentanediol and 1,6-hexanediol used. It is preferable to make it 0.1 mol% or more and 5 mol% or less. From the same viewpoint, it is more preferably 0.1 mol% or more and 1 mol% or less.

  The carbonate that is a raw material of the polycarbonate diol of the present embodiment is not particularly limited, but examples thereof include dialkyl carbonates such as dimethyl carbonate, diethyl carbonate, dipropyl carbonate, and dibutyl carbonate, diaryl carbonates such as diphenyl carbonate, ethylene carbonate, and trimethylene. Examples include carbonates, alkylene carbonates such as 1,2-propylene carbonate, 1,2-butylene carbonate, 1,3-butylene carbonate, and 1,2-pentylene carbonate. Among these, one or more carbonates can be used as a raw material. From the viewpoint of easy availability and easy setting of conditions for the polymerization reaction, it is preferable to use dimethyl carbonate, diethyl carbonate, diphenyl carbonate, dibutyl carbonate, or ethylene carbonate.

  In the production of the polycarbonate diol of the present embodiment, a catalyst may or may not be added. When adding a catalyst, it can select freely from a normal transesterification catalyst. For example, lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, zinc, aluminum, titanium, cobalt, germanium, tin, lead, antimony, arsenic, cerium and other metals, salts, alkoxides, organic compounds Used. Particularly preferred are titanium, tin and lead compounds. Moreover, the usage-amount of a catalyst can be 0.00001 to 0.1% normally with respect to the polycarbonate diol weight obtained.

  The polycarbonate diol production method of the present embodiment can be carried out in two stages. First, diol and carbonate are mixed at a molar ratio of 20: 1 to 1:10, and the first reaction is performed at 100 ° C. or more and 300 ° C. or less under normal pressure or reduced pressure. When dimethyl carbonate is used as the carbonate, the resulting methanol can be removed as a mixture with dimethyl carbonate to obtain a low molecular weight polycarbonate diol. When diethyl carbonate is used as the carbonate, the generated ethanol can be removed as a mixture with diethyl carbonate to obtain a low molecular weight polycarbonate diol. When ethylene carbonate is used as the carbonate, the resulting ethylene glycol can be removed as a mixture with ethylene carbonate to obtain a low molecular weight polycarbonate diol. Next, in the second stage reaction, heating is performed at 160 ° C. or more and 250 ° C. or less under reduced pressure to remove unreacted diol and carbonate, and to condense low molecular weight polycarbonate diol to obtain polycarbonate diol having a predetermined molecular weight. Can be obtained.

  The polycarbonate diol of this embodiment is used as a constituent material for paints, adhesives and pressure-sensitive adhesives, as a raw material for polyurethane and thermoplastic elastomers, and as a modifier for polyesters and polyimides, and as an additive for paints, adhesives and pressure-sensitive adhesives. It can be used for such applications. In particular, when used as a constituent material of paint, the compatibility with the curing agent is good, so the amount of solvent used can be reduced, and transparency, abrasion resistance, chemical resistance, hydrolysis resistance, heat resistance A coating film with a good balance of performance can be obtained. Further, when used as a raw material for polyurethane or thermoplastic elastomer, it is possible to reduce the solvent used for polymerization, and to obtain a polyurethane or thermoplastic elastomer that is tough and excellent in chemical resistance.

  The coating composition or thermoplastic polyurethane in this embodiment is obtained from the polycarbonate diol of the above embodiment and an organic polyisocyanate. The coating composition of this embodiment configured as described above exhibits excellent compatibility, and the thermoplastic polyurethane exhibits excellent toughness and chemical resistance.

  The coating film in this embodiment is obtained from the coating composition of this embodiment. The coating film of this embodiment configured as described above exhibits excellent chemical resistance, wear resistance, and transparency.

  Although it does not specifically limit as organic polyisocyanate used in this embodiment, For example, 2, 4-tolylene diisocyanate, 2, 6-tolylene diisocyanate and its mixture (TDI), crude TDI, diphenylmethane-4,4 '-Diisocyanate (MDI), crude MDI, naphthalene-1,5-diisocyanate (NDI), 3,3'-dimethyl-4,4'-biphenylene diisocyanate, polymethylene polyphenyl isocyanate, xylylene diisocyanate (XDI), phenylene Well-known aromatic diisocyanates, such as diisocyanate, are mentioned. Further, known aliphatic diisocyanates such as 4,4'-methylenebiscyclohexyl diisocyanate (hydrogenated MDI), hexamethylene diisocyanate (HMDI), isophorone diisocyanate (IPDI), and cyclohexane diisocyanate (hydrogenated XDI) are also included. Furthermore, the above-mentioned isocyanate isocyanurate-modified products, carbodiimidization-modified products, biuret-modified products, and the like can also be mentioned. These organic polyisocyanates may be used alone or in combination of two or more. These organic polyisocyanates may be used by masking isocyanate groups with a blocking agent.

  In the reaction of the polycarbonate diol and the polyisocyanate in the present embodiment, a chain extender as a copolymerization component can be used as desired. Although it does not specifically limit as said chain extender, For example, the usual chain extender in the polyurethane industry, ie, water, a low molecular polyol, a polyamine, etc. can be used. Specific examples of the chain extender are not particularly limited, but include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1 , 10-decanediol, 1,1-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, xylylene glycol, bis (p-hydroxy) diphenyl, bis (p-hydroxyphenyl) propane and other low molecular polyols, ethylenediamine, Examples include polyamines such as hexamethylenediamine, isophoronediamine, xylylenediamine, diphenyldiamine, and diaminodiphenylmethane. These chain extenders may be used alone or in combination of two or more.

  In the present embodiment, the paint includes the coating composition of the above embodiment.

  The paint in this embodiment includes, for example, a curing accelerator (catalyst), a filler, a dispersant, a flame retardant, a dye, an organic or inorganic pigment, a release agent, a fluidity modifier, a plasticizer, Antioxidants, ultraviolet absorbers, light stabilizers, antifoaming agents, leveling agents, colorants, solvents and the like can be added. However, it is not limited to the above, and the coating material in the present embodiment may contain various known additives depending on the purpose.

  In addition, thermosetting resin or photocurable resin can also be obtained using the polycarbonate diol, organic polyisocyanate, and hydroxyl-containing (meth) acrylate in this embodiment. As the hydroxyl group-containing (meth) acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 3-hydroxypropyl acrylate, 3-hydroxybutyl acrylate, 4-hydroxybutyl acrylate, hydroxyhexyl acrylate, 2-hydroxy-3-chloro Propyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 1,4-butylene glycol monoacrylate, glycerol monoacrylate, trimethylolpropane diacrylate, tetramethylol methane triacrylate, propylene glycol monoacrylate, polycaprolactone glycol monoacrylate, and The methacrylate with respect to these acrylates is mentioned. These can also be used independently and can also use 2 or more types together.

  Further, an aqueous polyurethane resin comprising a polycarbonate diol, an organic polyisocyanate, a urethane prepolymer composed of a compound having one hydrophilic center and at least two isocyanate-reactive functional groups, and a chain extender in the present embodiment. You can also get The compound having one hydrophilic center and at least two isocyanate-reactive functional groups is not particularly limited. For example, 2-dimethylolpropionic acid, 2,2-dimethylolbutyric acid, 2,2-dimethylol Valeric acid, lysine, cystine, 3,5-aminocarboxylic acid and the like can be used. Furthermore, from the viewpoint of emulsion stability, it is usually neutralized with a neutralizing agent. Examples of the neutralizing agent include, but are not limited to, trialkylamines such as trimethylamine, triethylamine, tri-n-propylamine, and tributylamine, N, N-dimethylethanolamine, N, N-dimethylpropanolamine, N, N-dipropylethanolamine, N, N-dialkylalkanolamines such as 1-dimethylamino-2-methyl-propanol, N-alkyl-N, N-dialkanolamines, trialkanolamines such as triethanolamine, hydroxylation Sodium, potassium hydroxide, lithium hydroxide, ammonia, trimethylammonium hydroxide, etc. are mentioned.

  In this embodiment, it does not specifically limit as a method of manufacturing a coating material, A various well-known manufacturing method can be used in the industry. For example, as a paint, a two-component solvent-based coating composition in which a main component composed of polycarbonate diol and a curing agent composed of organic polyisocyanate are mixed immediately before coating, an isocyanate terminal obtained by reacting polycarbonate diol and organic polyisocyanate. One-component solvent-based coating composition comprising a urethane prepolymer having a group, One-component solvent-based coating composition comprising a polyurethane resin obtained by reacting a polycarbonate diol, an organic polyisocyanate, and a chain extender; It can be produced as a one-component coating composition comprising a curable resin obtained by reacting a (meth) acrylate, a polycarbonate diol and an organic polyisocyanate, or a one-component aqueous coating composition. The “main agent” here is a main component for forming a coating film, and is a component excluding the curing agent.

  The solvent for the paint is not particularly limited. For example, dimethylformamide, diethylformamide, dimethylacetamide, dimethylsulfoxide, tetrahydrofuran, acetone, methyl ethyl ketone, methyl isobutyl ketone, dioxane, cyclohexanone, benzene, toluene, xylene, ethyl cellosolve, acetic acid Examples thereof include ethyl, butyl acetate, ethanol, isopropanol, n-butanol, and water. The paint can be used by mixing one or more of these solvents.

  Although it does not specifically limit as a method for obtaining the coating film of this embodiment from the coating composition of this embodiment as described above, for example, air spray coating, airless spray coating, rotary atomization coating, curtain coat coating, etc. The method of hardening at room temperature-200 degreeC after apply | coating to a to-be-coated article by a coating method of this, or using a roll, a brush, etc. can be used.

  In the present embodiment, the method for producing the thermoplastic polyurethane is not particularly limited, and a polyurethane forming reaction technique known in the polyurethane industry is used. For example, a thermoplastic polyurethane can be produced by reacting the polycarbonate diol of the present embodiment with an organic polyisocyanate at room temperature to 200 ° C. under atmospheric pressure. When a chain extender is used, it may be added from the beginning of the reaction or may be added from the middle of the reaction. Although it does not specifically limit about the manufacturing method of a thermoplastic polyurethane, For example, refer US Patent 5,070,173.

  In the polyurethane reaction, a known polymerization catalyst or solvent can be used. Although it does not specifically limit as a polymerization catalyst used, For example, a dibutyltin dilaurate can be mentioned.

  It is preferable to add a stabilizer such as a heat stabilizer (for example, an antioxidant) or a light stabilizer to the thermoplastic polyurethane of the present embodiment. Further, a plasticizer, an inorganic filler, a lubricant, a colorant, silicon oil, a foaming agent, a flame retardant, and the like may be added.

  Hereinafter, the present embodiment will be described more specifically with reference to examples, reference examples, and comparative examples, but the present embodiment is not limited to only these examples.

1. Determination of the composition of the polycarbonate diol 1 g of the sample obtained in each example to be described later is measured, and 1 g of the sample, 30 g of ethanol and 4 g of potassium hydroxide are put into a 100 mL eggplant flask and heated in an oil bath at 100 ° C. for 1 hour. did. After cooling to room temperature, 1-2 drops of phenolphthalein was added to the indicator and neutralized with hydrochloric acid. After cooling in the refrigerator for 3 hours and removing the precipitated salt by filtration, GC analysis was performed. The GC analysis uses a gas chromatography GC14B (manufactured by Shimadzu Corporation) with a DB-WAX (manufactured by J & W, USA) 30 m and a film thickness of 0.25 μm as a column, and diethylene glycol diethyl ester as an internal standard. A flame ionization detector (FID) was used. The temperature rising profile of the column was maintained at 60 ° C. for 5 minutes and then heated to 250 ° C. at 10 ° C./min.

In the polycarbonate diol, the ratio of the total repeating units represented by the above formulas (B), (C) and (D) to the repeating units represented by the above formula (A) (abbreviated as the main component ratio) is GC analysis. Based on the results, the following formula (1) was used.
Main component ratio (mol%) = {(B + C + D) / A} × 100 (1)
A: Number of moles of all diols B: Number of moles of 1,4-butanediol C: Number of moles of 1,5-pentanediol D: Number of moles of 1,6-hexanediol

In the polycarbonate diol, the ratio of the repeating unit represented by the above formula (B) to the total repeating units of the above formulas (B), (C), and (D) is represented by the following formula (2) based on the result of GC analysis. ).
Ratio (mol%) of formula (B) = B / (B + C + D) × 100 (2)

In this embodiment, the ratio (molar ratio) of the repeating units represented by the above formulas (C) and (D) was represented by the following formula (3) based on the results of GC analysis.
Formula (C): Formula (D) (molar ratio) = C: D (3)

2. Determination of the molecular weight of the polycarbonate diol The number average molecular weight of the polycarbonate diol was determined by determining the hydroxyl value by the “neutralization titration method (JIS K0070-1992)” in which titration was performed with an ethanol solution of potassium hydroxide using acetic anhydride and pyridine. It calculated using Formula (4).
Number average molecular weight = 2 / (OH value × 10 ⁻³ /56.1) (4)

3. Confirmation of properties of polycarbonate diol Copolycarbonate diol heated to 80 ° C. was placed in a 50 mL clear glass sample bottle and then cooled to room temperature. The copolycarbonate diol after cooling was visually observed, and the case where it was transparent and slightly fluid was expressed as liquid, and the case where it was not fluid was expressed as solid. The fluidity was evaluated by inclining the sample bottle by about 45 ° and observing the interface of the polycarbonate diol for about 1 minute. Transparency is evaluated by whether or not the back view can be visually recognized through the sample bottle when the sample bottle is observed from the front, and the state in which the back view is visible in all parts of the sample is transparent. did.

4). Mechanical Properties of Polyurethane Film A polyurethane film obtained from polycarbonate diol was cut into a 10 mm × 80 mm strip and cured for 3 days in a temperature-controlled room at 23 ° C. and 50% RH. Using a Tensilon tensile tester (ORIENTEC, RTC-1250A), 100% tensile stress (stress when the polyurethane film is stretched 50 mm; unit: MPa) at a distance between checks of 50 mm and a tensile speed of 100 mm / min, breaking strength ( Unit: MPa) and elongation at break (unit:%) were measured.

5. Chemical resistance of polyurethane film 0.1 g of oleic acid was attached to a test piece obtained by cutting a polyurethane film obtained from polycarbonate diol into a strip of 10 mm × 80 mm, and left at 20 ° C. for 4 hours. Was visually evaluated. In accordance with JISK5600-8-1, the degree and amount of defects were represented by grades 0 to 5 and defined as chemical resistance.

6). Abrasion resistance of coating film Using a coating film obtained from polycarbonate diol, it was measured according to JIS K5600-5-8, using a Taber type abrasion tester (TABER type No. 410 manufactured by Toyo Seiki Seisakusho). The weight before the abrasion test and the change in the weight of the coating film sample after the test (the number of abrasions of 500 times) were measured to evaluate the abrasion resistance.

7). Acid Resistance of Coating Film Using a coating film obtained from a polycarbonate diol, the appearance of the coating film after immersion in a 0.1 mol / L H ₂ SO ₄ aqueous solution at room temperature for 24 hours was visually evaluated. In accordance with JISK5600-8-1, the degree and amount of defects were represented by grades 0 to 5 and made acid resistant.

8). Alkali Resistance of Coating Film Using a coating film obtained from polycarbonate diol, the appearance of the coating film after being immersed in a 0.1 mol / L NaOH aqueous solution at room temperature for 24 hours was visually evaluated. According to JISK5600-8-1, the degree and amount of defects were represented by grades 0 to 5, and were regarded as alkali resistance.

9. Ethanol resistance of the coating film Using the coating film obtained from the polycarbonate diol, the appearance of the coating film was visually evaluated after being immersed in a 50% aqueous EtOH solution at room temperature for 4 hours. In accordance with JISK5600-8-1, the degree and amount of defects were represented by grades 0 to 5 and defined as ethanol resistance.

10. Transparency of coating film A coating film obtained from polycarbonate diol was immersed in distilled water at 90 ° C for 1 week. Then, the moisture was wiped off, and the cells were cured for 3 days in a thermostatic chamber at 23 ° C. and 50% RH. In accordance with JIS K 7136, the total light transmittance of the coating film before and after immersion was determined using a haze meter (Nippon Denshoku Industries Co., Ltd. NPH700), and the transparency of the coating film was determined from the following formula (5).
Transparency = F / E (5)
E: Total light transmittance (%) of the coating film before immersion
F: Total light transmittance (%) of the coated film after immersion

[Example 1]
In a 2 L glass flask equipped with a rectification column packed with a regular packing and a stirrer, 840 g (7.1 mol) of diethyl carbonate, 240 g (2.7 mol) of 1,4-butanediol, 1,5-pentanediol 360 g (3.5 mol) and 1,6-hexanediol 175 g (1.5 mol) were charged. Further, 0.5 g of titanium tetrabutoxide was added as a catalyst, and the mixture was stirred and heated at normal pressure. Next, the reaction was allowed to proceed for 15 hours while gradually raising the reaction temperature from 150 ° C. to 190 ° C. while distilling off the resulting mixture of ethanol and diethyl carbonate. Thereafter, the pressure was reduced to 15 kPa, and the mixture was further reacted at 190 ° C. for 8 hours while distilling off the mixture of diol and diethyl carbonate. The results of analyzing the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-1.

[Example 2]
The reaction was carried out using the apparatus shown in Example 1. 760 g (8.6 mol) of ethylene carbonate, 210 g (2.3 mol) of 1,4-butanediol, 550 g (5.3 mol) of 1,5-pentanediol and 115 g (1.0 mol) of 1,6-hexanediol were charged. . Further, 0.5 g of titanium tetrabutoxide was added as a catalyst, and the mixture was stirred and heated at normal pressure. Next, the reaction was allowed to proceed for 15 hours while gradually raising the reaction temperature from 150 ° C. to 190 ° C. while distilling off the resulting mixture of ethylene glycol and ethylene carbonate. Thereafter, the pressure was reduced to 14 kPa, and the reaction was further carried out at 190 ° C. for 8 hours while distilling off the diol and ethylene carbonate. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-2.

[Example 3]
740 g (8.4 mol) of ethylene carbonate, 170 g (1.9 mol) of 1,4-butanediol, 390 g (3.8 mol) of 1,5-pentanediol and 330 g (2.8 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 2 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-3.

[Example 4]
750 g (8.5 mol) of ethylene carbonate, 250 g (2.8 mol) of 1,4-butanediol, 370 g (3.6 mol) of 1,5-pentanediol and 265 g (2.3 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 2 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-4.

[Example 5]
750 g (8.5 mol) of ethylene carbonate, 230 g (2.6 mol) of 1,4-butanediol, 330 g (3.2 mol) of 1,5-pentanediol and 330 g (2.8 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 2 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-5.

[Example 6]
730 g (8.3 mol) of ethylene carbonate, 150 g (1.7 mol) of 1,4-butanediol, 340 g (3.3 mol) of 1,5-pentanediol and 400 g (3.4 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 2 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-6.

[Example 7]
880 g (7.5 mol) of diethyl carbonate, 285 g (3.2 mol) of 1,4-butanediol, 410 g (3.9 mol) of 1,5-pentanediol and 100 g (0.9 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-7.

[Example 8]
870 g (7.4 mol) of diethyl carbonate, 150 g (1.7 mol) of 1,4-butanediol, 280 g (2.7 mol) of 1,5-pentanediol and 420 g (3.6 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-8.

[Example 9]
880 g (10.0 mol) of ethylene carbonate, 240 g (2.7 mol) of 1,4-butanediol, 390 g (3.8 mol) of 1,5-pentanediol, 260 g (2.2 mol) of 1,6-hexanediol and 3- The reaction was allowed to proceed under the conditions shown in Example 2 using the apparatus of Example 1 except that 170 g (1.4 mol) of methyl-1,5-pentanediol was charged. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-9.

[Comparative Example 1]
Using the apparatus shown in Example 1, 800 g (6.8 mol) of diethyl carbonate and 850 g (7.2 mol) of 1,6-hexanediol were charged. Furthermore, 0.5 g of titanium tetrabutoxide was added as a catalyst, and the mixture was stirred and heated at normal pressure. Next, the reaction was allowed to proceed for 15 hours while gradually raising the reaction temperature from 150 ° C. to 190 ° C. while distilling off the resulting mixture of ethanol and dimethyl carbonate. Thereafter, the pressure was reduced to 15 kPa, and the mixture was further reacted at 190 ° C. for 8 hours while distilling off the mixture of diol and diethyl carbonate. The results of analyzing the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-10.

[Comparative Example 2]
Using the apparatus shown in Example 1, 620 g (7.1 mol) of ethylene carbonate, 310 g (3.4 mol) of 1,4-butanediol, 15 g (0.1 mol) of 1,5-pentanediol and 1,6-hexanediol 420 g (3.6 mol) was charged. Furthermore, 0.5 g of titanium tetrabutoxide was added as a catalyst, and the mixture was stirred and heated at normal pressure. Next, the reaction was allowed to proceed for 15 hours while gradually raising the reaction temperature from 150 ° C. to 190 ° C. while distilling off the resulting mixture of ethylene glycol and ethylene carbonate. Thereafter, the pressure was reduced to 14 kPa, and the reaction was further carried out at 190 ° C. for 8 hours while distilling off the diol and ethylene carbonate. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-11.

[Comparative Example 3]
700 g (8.0 mol) of ethylene carbonate, 10 g (0.1 mol) of 1,4-butanediol, 540 g (5.2 mol) of 1,5-pentanediol and 380 g (3.2 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Comparative Example 2 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-12.

[Comparative Example 4]
850 g (7.2 mol) of diethyl carbonate, 120 g (1.3 mol) of 1,4-butanediol, 320 g (3.1 mol) of 1,5-pentanediol and 400 g (3.4 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Comparative Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-13.

[Comparative Example 5]
860 g (7.3 mol) of diethyl carbonate, 360 g (4.0 mol) of 1,4-butanediol, 320 g (3.1 mol) of 1,5-pentanediol and 90 g (0.8 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Comparative Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-14.

[Comparative Example 6]
860 g (7.3 mol) of diethyl carbonate, 155 g (1.7 mol) of 1,4-butanediol, 220 g (2.1 mol) of 1,5-pentanediol and 480 g (4.1 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Comparative Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-15.

[Comparative Example 7]
860 g (7.3 mol) of diethyl carbonate, 140 g (1.6 mol) of 1,4-butanediol, 580 g (5.6 mol) of 1,5-pentanediol and 90 g (0.8 mol) of 1,6-hexanediol were charged. The reaction was allowed to proceed under the conditions shown in Comparative Example 1 using the apparatus of Example 1. The analysis results of the obtained polycarbonate diol are shown in Table 1. This polycarbonate diol is abbreviated as PC-16.

[Example 10]
A reactor equipped with a stirrer, a thermometer, and a cooling tube was charged with 200 g of PC-1 obtained in Example 1, 34 g of hexamethylene diisocyanate, and 0.02 g of dibutyltin dilaurate as a catalyst, and reacted at 70 ° C. for 5 hours. A prepolymer of terminal NCO was obtained. Next, after adding 600 g of dimethylformamide as a solvent and dissolving, 17 g of isophoronediamine as a chain extender was added and stirred at 35 ° C. for 1 hour. The obtained polyurethane resin solution was cast on a glass plate and allowed to stand at room temperature for 30 minutes to volatilize the solvent, and then dried with a dryer at 100 ° C. for 2 hours to obtain a thickness of 0.09 to 0.11 mm. A polyurethane film was obtained. Table 2 shows the results of physical property evaluation using the polyurethane film.

[Examples 11 to 18]
A polyurethane film was obtained under the conditions shown in Example 10 using PC-2 to 9 as the polycarbonate diol. Table 2 shows the results of physical property evaluation using the polyurethane film.

[Comparative Examples 8-14]
A polyurethane film was obtained under the conditions shown in Example 10 using PC-10 to 16 as the polycarbonate diol. Table 2 shows the results of physical property evaluation using the polyurethane film.

[Example 19]
40g of polycarbonate diol PC-1, 0.75g of BYK-331 (manufactured by BYK Chemical) as a leveling agent, and 1 dibutyltin dilaurate solution dissolved in thinner (xylene / butyl acetate = 70/30) to 2% by weight .25 g and thinner 40 g were prepared. These were mixed and stirred to obtain a paint base. 7.5 g of Duranate TPA-100 (manufactured by Asahi Kasei Chemicals Co., Ltd., NCO content: 23.1%) was added as a curing agent to prepare a coating solution. This coating solution was applied on a glass plate and allowed to stand at room temperature for 2 hours to volatilize the thinner. Then, it heat-hardened at 80 degreeC for 2 hours, and obtained the coating film whose thickness is 40-50 micrometers. Table 3 shows the results of physical property evaluation using the coating film.

[Examples 20 to 27]
A coating film was obtained under the conditions shown in Example 19 using PC-2 to 9 as the polycarbonate diol. Table 3 shows the results of physical property evaluation using the coating film.

[Comparative Examples 15 to 21]
A coating film was obtained under the conditions shown in Example 19 using PC-10 to 16 as the polycarbonate diol. Table 3 shows the results of physical property evaluation using the coating film.

  The polycarbonate diol according to an embodiment of the present invention is easy to handle and exhibits good compatibility with a curing agent, and reduces the amount of solvent used when used as a paint or when a polyurethane resin is produced by polymerization. It becomes possible. In addition, as demonstrated in the above-described examples, when the polycarbonate diol according to an embodiment of the present invention is used as a raw material for polyurethane or thermoplastic elastomer, polyurethane or thermoplastic elastomer rich in toughness and chemical resistance is used. Can be obtained. In addition, when used as a raw material for a paint, since the compatibility with the curing agent is good, a coating film excellent in wear resistance and chemical resistance can be obtained. Therefore, the polycarbonate diol according to one embodiment of the present invention can be suitably used as a raw material for polyurethane, thermoplastic elastomer, and the like, and further as a constituent material for paints and adhesives.

Claims (5)

A polycarbonate diol having a repeating unit represented by the following formula (A) and a terminal hydroxyl group,
At least a part of the repeating unit represented by (A) is a repeating unit represented by the following formulas (B), (C), and (D):
The total of the repeating units represented by (B), (C) and (D) is 80 mol% or more and 100 mol% or less of the repeating units represented by (A),
With respect to the total of the repeating units represented by (B), (C), and (D), the repeating unit represented by (B) is 18 mol% or more and 40 mol% or less,
The polycarbonate diol whose ratio of the repeating unit represented by said (C) and (D) is 40: 60-85: 15 by molar ratio.   The polycarbonate diol according to claim 1, which is liquid when heated to 80 ° C and then cooled to room temperature.   A thermoplastic polyurethane obtained from the polycarbonate diol according to claim 1 or 2 and an organic polyisocyanate.   A coating composition comprising the polycarbonate diol according to claim 1 or 2 and an organic polyisocyanate.   A coating film obtained from the coating composition according to claim 4.