JPH11322876A - Dispersant for non-aqueous emulsion polymerization and production of polyurethane using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing the subject dispersant with high dispersing ability, and to provide a method for producing a polyurethane using the dispersant. SOLUTION: This method for producing a dispersant for non-aqueous emulsion polymerization with high dispersing ability comprises copolymerization between 100 pts.wt. of a secondary carbon-bearing polyol and 20-400 pts.wt. of an acrylic ester monomer having >=2C hydrocarbon group on the side chain. The other objective method for producing a polyurethane by non-aqueous emulsion polymerization comprises addition of the above dispersant at 0.5-20.0 wt.% based on the final polyurethane.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for producing a dispersant used for producing a polyurethane by non-aqueous emulsion polymerization and a method for producing a polyurethane using the dispersant.

[0002]

2. Description of the Related Art Conventionally, a dispersant for non-aqueous emulsion polymerization comprises a polyol having an unsaturated group in a molecule comprising a hydrocarbon group having 6 or more carbon atoms, as shown in, for example, Japanese Patent Publication No. 5-47564. What reacted the ethylenically unsaturated monomer which has a side chain was used.

[0003]

However, since the conventional dispersant uses a polyol having an unsaturated group in the molecule, it has been necessary to produce the polyol by, for example, reacting maleic anhydride with the polyol. Since this reaction is carried out at a relatively high temperature, gelation is caused by the intermolecular crosslinking of unsaturated groups, or when the reaction is carried out at a low temperature, a terminal carboxylic acid is generated due to insufficient reaction, so that a desired polyol cannot be obtained. In addition, when the unsaturated polyol having a unsaturated group is used as a part of the raw material during the production of the polyester polyol, the above-mentioned problem occurs. The present invention aims to remedy this problem.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve such conventional problems, and as a result, have found a method for obtaining a dispersant using a polyol having no unsaturated group in the molecule. The present invention has been completed. That is,
According to the present invention, non-aqueous emulsion polymerization having excellent dispersibility obtained by polymerizing 20 to 400 parts by weight of an acrylate monomer having a hydrocarbon group having 2 or more carbon atoms in a side chain to 100 parts by weight of a polyol having a secondary carbon. A method for producing a dispersant for polyurethane and a method for producing a polyurethane by non-aqueous emulsion polymerization, wherein the dispersant is 0.5 to 20.0% by weight based on the polyurethane.
There is provided a method for producing a polyurethane, characterized by being added.

[0005]

DETAILED DESCRIPTION OF THE INVENTION The polyol having a secondary carbon used in the present invention is, for example, 3-methyl-1,5 pentanediol, 2,4-diethyl-1,5 pentanediol, 2-methyl-1, 3-propanediol, 2,2
Polyesters obtained by ordinary esterification from glycols having a secondary carbon in the molecule, such as 4-trimethyl-1,5 pentanediol and 2,7-dimethyl-1,8-octanediol, and polycarboxylic acids Polyol, a polyol obtained by ring-opening polymerization of a cyclic monomer such as ethylene oxide, propylene oxide, tetrahydrofuran, ε-caprolactone, etc., starting from a glycol having a secondary carbon in the molecule, Examples of the polycarbonate polyol include a glycol having a secondary carbon and a carbonate compound such as dimethyl carbonate, diethyl carbonate, diphenyl carbonate, ethylene carbonate, and propylene carbonate. Further, polyether polyols by addition polymerization of propylene oxide, polyester polyols by β-methyl δ-valerolactone, and hydrogenated polyisoprenes having terminal OH can also be mentioned. Those polyols having a molecular weight of 200 to 10000 can be used. Polyester polyols composed of glycols having a secondary carbon and a polycarboxylic acid can be prepared by known synthetic methods, for example, polycarboxylic acids, glycols having a secondary carbon in an excess molar number of the polycarboxylic acid, and titanium or tin-based compounds. , And the resulting water is distilled off, and then heated to 180 to 210 ° C. while reducing the pressure. The glycol having a secondary carbon used in the present invention can be used in combination with a commonly used glycol such as ethylene glycol, 1,4 butanediol, 1,6 hexane glycol and the like, if necessary.

The acrylate monomer having a hydrocarbon group having 2 or more carbon atoms in the side chain of the present invention (hereinafter abbreviated as a side chain-containing monomer) comprises acrylic acid and / or methacrylic acid and an alcohol having 2 or more carbon atoms. And acrylates such as ethyl methacrylate, isopropyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, 2-ethylhexyl methacrylate, and stearyl methacrylate. The side chain-containing monomer of the present invention, if necessary, other vinyl monomers such as styrene, acrylonitrile,
Vinyl chloride, vinyl acetate, vinyl pivalate, vinyl laurate and the like can be added.

As a method for polymerizing the side chain-containing monomer of the present invention on the polyol having a secondary carbon of the present invention, all ordinary polymerization methods for vinyl monomers can be applied. For example, in the case of polymerization using a radical polymerization initiator, a part of benzoyl peroxide (BPO) as a radical initiator is added to a polyol and heat-treated at 100 ° C., and a mixture of BPO and a side chain-containing monomer is added to a polyol at 100 ° C. Can be polymerized by allowing the monomer to react by dropping the mixture. The polymerization of the side chain-containing monomer of the present invention into a polyol is to graft the side chain-containing monomer onto the secondary carbon in the polyol. In the case of a polyol containing only primary carbon, grafting is difficult, and the resulting polymer has extremely low dispersant performance. In the polymerization of the side chain-containing monomer of the present invention, a polymerization catalyst is preferably used. As a polymerization catalyst, for example,
Organic peroxides such as benzoyl peroxide (BPO), lauroyl peroxide, tert-butyl perbenzoate, diisopropyl peroxydicarbonate, azo compounds such as α, α′-azobisisobutyronitrile, hydrogen peroxide And a redox polymerization initiator based on a combination of iron and a ferrous salt. In the polymerization of the side chain-containing monomer of the present invention, a solvent can be used if necessary. Examples of the solvent include butyl acetate, cyclohexane, n-heptane, isoparaffin, dioctyl phthalate, dioctyl adipate, dibutyl phthalate and the like.

[0008] The amount ratio of the polyol having a secondary carbon and the side chain-containing monomer of the present invention is preferably 100/20 to 400 (weight). When the amount of the side chain-containing monomer is less than 20 parts by weight with respect to 100 parts by weight of the polyol, the performance as a dispersant deteriorates, and it becomes necessary to increase the amount of the dispersant to be prepared when producing polyurethane, which is economically disadvantageous. Becomes Further, if the side chain-containing monomer exceeds 400 parts by weight with respect to 100 parts by weight of the polyol, the balance between polarity and non-polarity is lost during non-aqueous emulsion polymerization, and the effect as a dispersant cannot be exerted. .

The dispersant for non-aqueous emulsion polymerization of the present invention can be used as a dispersant for producing polyurethane by a non-aqueous emulsion polymerization method. A method for producing a polyurethane by a non-aqueous emulsion polymerization method is described in JP-B-57-29485 and JP-B-5-4.
7564 and the like. The polyurethane of the present invention can be produced by a known method. Since the dispersant for non-aqueous emulsion polymerization of the present invention has a polyol as a skeleton, it is bonded to a polyurethane chain during polyurethane production. When not bonded to a polyurethane chain, the hydroxyl group of the dispersant of the present invention can be blocked with a monocarboxylic acid, a monoisocyanate, or the like.

The polyurethane produced by the non-aqueous emulsion polymerization method of the present invention includes ordinary thermoplastic polyurethane resins, incomplete thermoplastic polyurethane resins containing reactive groups such as isocyanate groups, thermosetting polyurethane resins, polyurethane gels and the like. It is. As the raw materials used for producing these polyurethanes, all known raw materials can be used.

The thermoplastic polyurethane resin produced by the non-aqueous emulsion polymerization method is prepared by dispersing a polyisocyanate such as diphenylmethane diisocyanate, hexamethylene diisocyanate, or a polyester polyol having a molecular weight of 500 to 4000 in an organic solvent such as isoparaffin. Such a polyol and a chain extender such as 1,4 butanediol are charged, and additives such as a catalyst are added if necessary, and the mixture is reacted at 60 to 120 ° C. to form a discontinuous particulate polyurethane in an organic solvent. Obtained by generating. The particulate polyurethane in this organic solvent is
If necessary, the organic solvent can be removed by filtration or the like to obtain a powdered polyurethane.

The dispersant for non-aqueous emulsion polymerization of the present invention, which is used when producing a polyurethane by non-aqueous emulsion polymerization, is added in an amount of 0.5 to 20.0% by weight based on the polyurethane.
0 to 5.0% by weight is preferred. When the addition amount is less than 0.5%, the dispersing ability is reduced, and the polyurethane may not be formed into particles in the organic solvent. On the other hand, if it exceeds 20.0%, the properties of the dispersant, for example, a decrease in hardness may be unfavorable because the polyurethane is too strong. The polyurethane using the dispersant of the present invention can be widely used in various molding materials, powder coatings, various modifiers, fillers, and the like.

[0013]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 (1) Synthesis of Dispersant 1 A 500 ml four-necked flask was equipped with a stirrer, a thermometer, a dropping funnel, and a cooler.
30 g of 1,5 pentanediol adipate diol,
Weigh 0.5 g of benzoyl peroxide and 66.6 g of dioctyl phthalate. While flowing nitrogen gas into the system, 1
Heat and mix at 00 ° C for 1 hour. At 100 ° C., a dissolved mixture of 70 g of lauryl methacrylate and 0.9 g of benzoyl peroxide was added dropwise from the dropping funnel over 1.5 hours.
Thereafter, the mixture was reacted at 130 ° C. for 3 hours to obtain a dispersant 1
I got (2) Synthesis of polyurethane A 500 ml four-necked flask was equipped with a stirrer, a thermometer, a cooler, and the like, and 100 g of polybutylene adipate diol having a molecular weight of 1,000, 10.8 g of the above dispersant 1 and Isopar G (manufactured by Exxon Chemical, isoparaffin) Solvent)
66 g was charged and heated and mixed at 60 ° C. for 1 hour in a nitrogen gas atmosphere. 1,6 hexamethylene diisocyanate 2
5.2 g was added and reacted at 80 ° C. for 3 hours. 66 g of Isopar G, 4.5 g of 1,4-butanediol and 0.013 g of dibutyltin dilaurate (DBTDL) were added, and reacted at 80 ° C. for 3 hours to obtain polyurethane particles dispersed in a solvent. The solvent was separated and removed to obtain 125 g of a spherical thermoplastic polyurethane resin having a particle size of 10 to 200 μm.

Example 2 (1) Synthesis of Dispersant 2 Using the same apparatus as in Example 1 (1),
-Methyl-1,5 pentanediol Instead of adipatediol, 2,4-diethyl-1,2000 having a molecular weight of 2,000 was used.
The synthesis was performed in the same manner as in Example 1 (1) except that 5-pentanediol / 1,6 hexamethylene glycol (3/7 molar ratio) adipate diol was used, and 2-ethylhexyl methacrylate was used instead of lauryl methacrylate. Inventive dispersant 2 was obtained. (2) Synthesis of Polyurethane A 500 ml four-necked flask was equipped with a stirrer, a thermometer, a cooler, etc., and 100 g of polytetramethylene glycol having a molecular weight of 1,000, 10.8 g of the above dispersant 2 and Isopar G (manufactured by Exxon Chemical, isoparaffin) Solvent) 6
6 g was charged and heated and mixed at 60 ° C. for 1 hour in a nitrogen gas atmosphere. 1,6 hexamethylene diisocyanate 2
5.2 g was added and reacted at 80 ° C. for 3 hours. 66 g of Isopar G, 4.5 g of 1,4 butanediol and 0.013 g of dibutyltin dilaurate (DBTDL)
Was added and reacted at 80 ° C. for 3 hours to obtain polyurethane particles dispersed in a solvent. The solvent was separated and removed to obtain 120 g of a spherical thermoplastic polyurethane resin having a particle size of 20 to 500 microns.

Example 3 (1) Synthesis of Dispersant 3 Using the same apparatus as in Example 1 (1),
-Examples except that 2,2,4-trimethyl-1,5 pentanediol / 1,6 hexamethylene glycol (2/8 molar ratio) adipate diol was used instead of -methyl-1,5 pentane diol adipate diol 1 (1)
And dispersant 3 of the present invention was obtained. (2) Synthesis of Polyurethane A 1000 ml four-necked flask was equipped with a stirrer, a thermometer, a cooler, and the like, and 200 g of 3-methyl-1,5 pentanediol adipate diol having a molecular weight of 2000, 10.1 g of the above dispersant 3, and n -123 g of heptane was charged, and heated and mixed at 60 ° C for 1 hour in a nitrogen gas atmosphere.
33.6 g of 1,6 hexamethylene diisocyanate was added and reacted at 70 ° C. for 4 hours. n-heptane 123
g) 9.0 g of 1,4 butanediol and 0.02 g of dibutyltin dilaurate (DBTDL) are added,
The reaction was carried out at a temperature of 5 ° C. for 5 hours to obtain polyurethane particles dispersed in a solvent. The solvent is separated and removed, and the particle size is 30 to 400.
240 g of micron spherical thermoplastic polyurethane resin
Obtained.

Example 4 (1) Synthesis of Polyurethane Gel A polyfunctional polyester polyol (trade name: Nipporan 800, Nippon Polyurethane Industry Co., Ltd.) was heated to 60 ° C. in a 500 ml four-necked flask equipped with a stirrer, a thermometer, a cooler and the like. 290 mg KOH / g), 117.8 g of the dispersant of Example 1, 27.4 g of 1,6 hexamethylene diisocyanate and 92.9 g of cyclohexane
And heated and mixed at 60 ° C. for 1 hour in a nitrogen gas atmosphere. 0.05 g of dibutyltin dilaurate was added,
The reaction was carried out at 70 ° C. for 5 hours to obtain polyurethane gel particles dispersed in a solvent. The solvent is separated and removed to give a particle size of 50.
92 g of a ~ 300 micron spherical polyurethane gel was obtained.

Comparative Example 1 The synthesis of (1) a polyol having an unsaturated bond in the molecule of Example 2 of JP-B-5-47564 was carried out. A 2-liter four-necked flask was equipped with a stirrer, a thermometer, a distilling tower, and a nitrogen gas inlet tube, and 1000 g of polybutylene adipate having a molecular weight of 1,000 (trade name: Nipporan 4009, manufactured by Nippon Polyurethane Industry Co., Ltd., hydroxyl value: 110 mgKOH / g)
Then, 49 g of maleic anhydride was weighed out, and heated and mixed while flowing nitrogen gas. After the condensation water is taken out of the system at 140 to 160 ° C., the reaction is continued while gradually reducing the pressure in the system,
Finally, the reaction was carried out at 190 ° C. and 30 mmHg for 4 hours. Since the acid value of the polyol was 5.3 mgKOH / g, it was further reacted under the same conditions for 20 hours. Acid value is 2.9
, But the viscosity increased, and some gel-like products were observed. This polyol could not be used for dispersant synthesis.

[0019]

The dispersant for non-aqueous emulsion polymerization obtained by the present invention has excellent dispersibility in the production of polyurethane powder and the like, and further reacts with the polyisocyanate as a diol component in the production of polyurethane. Good physical properties can be maintained without bleeding in products. Polyurethane obtained by the present invention, various molding materials, powder coatings, various modifiers, fillers,
There are a wide range of applications such as paints and adhesives.

Claims (2)

[Claims] 1. A non-aqueous emulsifier having excellent dispersibility obtained by polymerizing 20 to 400 parts by weight of an acrylate monomer having a hydrocarbon group having 2 or more carbon atoms in a side chain to 100 parts by weight of a polyol having a secondary carbon. A method for producing a dispersant for polymerization. 2. The process for producing a polyurethane by non-aqueous emulsion polymerization, wherein the dispersant according to claim 1 is added to the polyurethane in an amount of 0.1 to 0.1%.
A method for producing a polyurethane, comprising adding 5 to 20.0% by weight.