JPH0547564B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for producing a dispersant with excellent dispersibility, which is used when producing a polyurethane powder polymer by a non-aqueous dispersion polymerization method.

[Conventional technology]

A method for producing polyurethane powder using a non-aqueous dispersion polymerization method has already been described by Matsumoto et al. (Journal of Japan Adhesive Association, 9 .
183.1973) has provided an explanation of the basic polymerization methods. In addition, in Special Publication No. 57-29485,
A method for producing polyurethane powder by non-aqueous dispersion (emulsion) polymerization is described. The most important point in this polymerization method is the selection of the dispersant. In Japanese Patent Publication No. 57-29485, a copolymer of a monomer having a long chain alkyl such as lauryl methacrylate and a monomer such as methyl methacrylate or acrylamide is used as a dispersant. This dispersant has a low dispersing ability, and depending on the composition of the polyurethane, the dispersion may be insufficient. Also,
Conventional dispersants are of the additive type, and therefore, molded articles of polyurethane polymers may seep out of the dispersant over time, causing problems such as changes in appearance.

[Problem that the invention seeks to solve]

In order to improve the poor dispersion performance, which is a drawback of conventional dispersants, the inventors of the present invention have conducted intensive research and examination on the composition of dispersants, and as a result, they have created an unsaturated bond in polyol, which is one of the raw materials for polyurethane. ,
The present inventors have discovered a dispersant in which an ethylenically unsaturated monomer having a hydrocarbon side chain is graft-polymerized, and have completed the present invention.

[Means for solving problems]

That is, the present invention provides a polyol obtained by adding an unsaturated bond-containing glycol or an unsaturated group-containing dicarboxylic acid to a reaction between a glycol and a dibasic acid, or a polyester polyol or a polycarbonate polyol and an unsaturated bond-containing dicarboxylic acid. It consists of a polyol obtained by reaction, and has 1 to 10 moles of unsaturated bonds and 2 active hydrogen groups per molecule (hereinafter abbreviated as polyol with unsaturated bonds).The number of carbon atoms per 100 parts by weight of polyol. 20 to 400 parts by weight of an ethylenically unsaturated monomer having a side chain consisting of 6 or more hydrocarbon groups (hereinafter abbreviated as ethylenically unsaturated monomer) and 0.4 parts by weight of a reaction initiator.
1. A method for producing a dispersant for non-aqueous dispersion polymerization for producing polyurethane, which comprises dropping a mixed solution of up to 8.1 parts by weight and then reacting.

It is related to.

The dispersant of the present invention can be effectively used for producing polyurethane of any composition by non-aqueous dispersion polymerization. In addition, molded polyurethane obtained by non-aqueous dispersion polymerization does not change over time due to seepage of the dispersant because the dispersant reacts with the polyisocyanate.

As polyols having unsaturated bonds that can be used in the present invention, for example, in the case of polyester polyols, unsaturated group-containing glycols or unsaturated group-containing dicarboxylic acids are used as part of the raw material glycols, dibasic acids, etc. Examples include those manufactured by Further, in the case of polyether polyols, those produced using unsaturated group-containing glycols as a starting material can also be mentioned. Furthermore, hydroxyl group-terminated polyester with a molecular weight of 2000 or less,
Also included are polyols obtained by esterifying polyethers, polycarbonates, etc. with unsaturated group-containing dicarboxylic acids. Examples of the unsaturated group-containing glycol mentioned here include 2-butene-1,4-diol, glycerin monoallyl ether, and the like. Examples of unsaturated group-containing dicarboxylic acids include maleic acid and itaconic acid. The molecular weight and unsaturated bond concentration of the polyol having unsaturated bonds that can be used in the present invention are not particularly limited, but the molecular weight is 3000 or less,
The unsaturated bond concentration is 1 to 1 per polyol molecule.
10 moles of unsaturated groups are preferred.

The polyol having an unsaturated bond of the present invention can be produced by a conventional method for producing polyester, polyether, etc.

Ethylenically unsaturated monomers used in the production of the dispersant in the present invention include, for example, 1-octene, 1- or 2-nonene, 1- or 2-decene, 1- or 2-heptadecene, 2-methyl -Aliphatic linear chains containing vinyl, propenyl or isopropenyl groups such as -1-nonene, 2-methyl-1-decene, 2-methyl-1-dodecene, 2-methyl-1-hexadecene, 2-methyl-1-heptadecene, etc. A combination of an unsaturated hydrocarbon, acrylic acid or methacrylic acid, and an aliphatic alcohol having 6 or more carbon atoms such as 2-ethylhexyl alcohol or hexyl alcohol, or an alicyclic alcohol having 6 or more carbon atoms such as cyclohexanol, norbonanol, or adamantanol. Examples include esters. These can be used alone or in combination of two or more.

In the reaction for obtaining a non-aqueous dispersion polymerization dispersant for producing polyurethane from a polyol having an unsaturated bond and an ethylenically unsaturated monomer in the present invention, for example, a polyol having an unsaturated bond is mixed with an ethylenically unsaturated monomer. The mixture of polymer and reaction initiator is
After dropping at 110°C, the mixture was heated to 130°C for 2 hours.

As a reaction initiator, benzoyl peroxide, which is a radical initiator, can be used.

In the reaction of the present invention, a solvent can be used as necessary. For example, all solvents commonly used in the polymerization of ethylenic monomers, such as butyl acetate, cyclohexane, and n-heptane, can be used.

Furthermore, the ratio of the polyol having unsaturated bonds to the ethylenically unsaturated monomer is 100/20 to 400 (by weight)
is desirable. The amount of the reaction initiator used is 0.4 to 8.1 parts by weight based on the amount of the ethylenically unsaturated monomer. If the amount of the ethylenically unsaturated monomer is less than 20 parts by weight per 100 parts by weight of the polyol, its performance as a dispersant will deteriorate, and when producing polyurethane, it will be necessary to increase the amount of dispersant charged, resulting in economical problems. be disadvantageous. Polyol 100 with unsaturated bonds
If the amount of the ethylenically unsaturated monomer exceeds 400 parts by weight, the balance between polarity and non-polarity will be lost during non-aqueous dispersion polymerization, and the dispersant will no longer be effective.

The dispersant for non-aqueous dispersion polymerization of the present invention can be used as a dispersant when producing polyurethane by a non-aqueous dispersion polymerization method. These include incompletely thermoplastic polyurethane resins containing isocyanate groups or blocked isocyanate groups, or thermosetting polyurethane resins.

Polyurethanes are basically composed of polyols, chain extenders and polyisocyanates.

Polyurethane using the dispersant of the present invention can be used in a wide range of applications such as various molding materials, powder coatings, various modifiers, and fillers.

〔Example〕

Next, the present invention will be explained in more detail with reference to Examples.

Example 1 (1) Synthesis of polyol having an unsaturated bond in the molecule A four-necked flask was equipped with a stirrer, a thermometer,
Distillation tower, equipped with _N2 gas inlet pipe, adipic acid 660
g, maleic anhydride 98g, ethylene glycol
Weigh out 410g and 0.05g of stannous octenoate.
Heat and mix while flowing _N2 gas. 120~160
After letting the condensed water out of the system at ℃, the reaction continued while gradually reducing the pressure inside the system, and finally the temperature was 190℃ and 30 mm.
The reaction was completed after 4 hours of reaction under Hg conditions.
The obtained polyester has a hydroxyl value of 104mgKOH/
g, and the acid value was 2.6 mgKOH/g. This polyester has a molecular weight of 1170 and an average of 1 mole of double bonds per molecule.

(2) Synthesis of dispersant A 500ml four-necked flask with a stirrer, thermometer,
Attach a dropping funnel and a condenser, and weigh out 74 g of the polyol synthesized in (1) and 99 g of butyl acetate. _N2
The gas is heated and mixed while flowing into the system from the top of the dropping funnel. When the temperature reached 110℃, 2-ethylhexyl methacrylate 74 was added from the dropping funnel.
1.5 g of benzoyl peroxide was added dropwise. The dropwise addition was completed in 1 hour, and the reaction was then allowed to proceed at 130°C for 2 hours to complete the reaction.
The hydroxyl value of this dispersant was 41 mgKOH/g.

(3) Application example (synthesis of polyurethane powder) A 500ml four-necked separable flask is equipped with a propeller-type blade stirrer, a thermometer, and a cooler.
9.1 g (0.003 mol) of the dispersant obtained in polyethylene adipate with a molecular weight of 1000 heated to 60°C.
57.2g (0.057mol), 1,4-butanediol
Add 5.1g (0.057mol) and mix uniformly.
Diphenylmethane diisocyanate 29.3 at 50℃
g (0.117 mol) and mixed uniformly,
Selsol 71 (Shell sol71 manufactured by Shell Chemical, boiling point
Add 91g of paraffin (same below) at 170-200°C and stir at high speed (approximately 1000 rpm) to emulsify.
Next, 0.01 g of dibutyltin dilaurate was added, and the stirring speed was reduced (approximately 600 rpm) to allow reaction at room temperature for 1 hour. The temperature was raised to 70°C and the mixture was reacted for 3 hours to obtain a particulate polyurethane polymer dispersed in Celsol 71. This dispersion was allowed to stand, and the supernatant liquid was removed by decantation.
Polyurethane powder was obtained by drying under reduced pressure. This powder had a main particle size of about 20-150 μm.

Example 2 (1) Synthesis of polyol having an unsaturated bond in the molecule In a flask similar to that used in Example 1 (1), polybutylene adipate with a molecular weight of 1000 (trade name Nitsuporan 4009, manufactured by Nippon Polyurethane Industries) was added. , hydroxyl value 110 mgKOH/g) and 49 g of maleic anhydride were weighed out and mixed under heating while flowing N ₂ gas. After the condensed water was discharged from the system at 140 to 160°C, the reaction was continued while gradually reducing the pressure inside the system, and the reaction was finally completed after 4 hours of reaction at 190°C and 30 mmHg. Polyester has a hydroxyl value of 53 mgKOH/g and an acid value of 4.1 mgKOH/g.
It was hot. This polyester has a molecular weight of 2100,
It has an average of 1 mole of double bonds in one molecule.

(2) Synthesis of dispersant Into a flask similar to that used in Example 1 and (2), 44 g of the polyol synthesized in (1) and 99 g of butyl acetate were weighed. Heat and mix while flowing _N2 gas into the system from the top of the dropping funnel.
When the temperature reached 110°C, a dissolved mixture of 51 g of 2-ethylhexyl methacrylate, 51 g of lauryl methacrylate, and 2 g of benzoyl peroxide was started to be added dropwise from the dropping funnel. The dropwise addition was completed in 1.5 hours, and the reaction was then allowed to proceed at 130°C for 2 hours to complete the reaction. The hydroxyl value of this dispersant is
It was 11mgKOH/g.

Example 3 (1) Synthesis of polyol having unsaturated bonds in the molecule In a flask similar to that used in Example 1, (1), polyhexamethylene carbonate diol with a molecular weight of 1000 (trade name Nitsuporan 981, manufactured by Nippon Polyurethane Industries) was added. made, hydroxyl value 115mgKOH/g) 980
g and 49 g of maleic anhydride were weighed out and reacted in the same manner as in Example 1, (1). The obtained polyol had a hydroxyl value of 57 mgKOH/g and an acid value of 4.2 mg.
It was KOH/g. This polyol has a molecular weight
In 1970, it has an average of 1 mole of double bonds in one molecule.

(2) Synthesis of dispersant Into a flask similar to that used in Example 1 and (2), 44 g of the polyol synthesized in (1) and 99 g of butyl acetate were weighed. Heat and mix while flowing _N2 gas into the system from the top of the dropping funnel.
When the temperature reached 110°C, dropwise addition of a dissolved mixture of 103 g of lauryl methacrylate and 2 g of benzoyl peroxide was started from the dropping funnel.
The dropwise addition was completed in 1.5 hours, and the reaction was then allowed to proceed at 130°C for 2 hours to complete the reaction. The hydroxyl value of this dispersant was 13 mgKOH/g.

Reference Example 1 A polyurethane powder was synthesized using the dispersant synthesized in Example 3.

In a flask similar to that used in Example 1, (3),
Example 3, 9.1 g (0.001 mol) of the dispersant obtained in (2), polyhexamethylene carbonate diol with a molecular weight of 1000 (Nituporan 981,
55.7g (0.057mol) of hydroxyl value 115mgKOH/g,
5.1 g (0.057 mol) of 1,4-butanediol is charged and mixed uniformly. 4,4'-dicyclohexylmethane diisocyanate 30.1g (0.115mol)
Add and mix evenly, then add 100g of Selsol 71
Add and stir at high speed (approximately 1000 rpm) to emulsify. Next, add 0.03g of dibutyltin dilaurate.
Add the mixture, reduce the stirring speed (approximately 600 rpm), and
The reaction was allowed to take place at room temperature for an hour. The temperature was raised to 90°C and the reaction was carried out for 9 hours to obtain a particulate polyurethane polymer dispersed in Celsol 71. The solvent was removed from this dispersion under reduced pressure to obtain polyurethane powder. The main particle size of this powder was 20 to 150 μm. A sheet was molded from this polyurethane powder. A 200 x 200 mm iron plate coated with a silicone-based mold release agent was heated to 200°C, and the polyurethane powder of the present invention was dropped onto the iron plate and melt-molded. Further 160~180℃, 15~
Press for 5 minutes under pressing conditions of 20Kg/cm ² to determine the thickness.
A 0.5 mm pressed sheet was obtained. this sheet
Mechanical strength was determined using the JISK6723 method.
The tensile strength was 530 Kg/cm ² and the elongation was 280%.

Comparative Example 1 (1) Synthesis of dispersant 97.7 g of Selsol 71 was charged into a flask similar to that used in Example 1 and (2), and heated while flowing N ₂ gas into the system from the top of the dropping funnel. did. A mixture of 119 g (0.47 mol) of lauryl methacrylate, 27.5 g (0.28 mol) of methyl methacrylate and 2.5 g of benzoyl peroxide prepared in advance was added dropwise over 2 hours at the same temperature with stirring. The temperature was raised to 140°C and the mixture was reacted for 4 hours to obtain a dispersant.

(2) Synthesis of polyurethane powder Emulsification was carried out in the same manner as in Examples 1 and (3) except that 9.1 g of the dispersant from (1) was used as the dispersant. As a result, the reactant was poorly dispersed in Celsol 71 and became lumpy.

〔Effect of the invention〕

The dispersant for non-aqueous dispersion polymerization obtained by the present invention has excellent dispersion performance in the production of polyurethane powder, and also reacts with polyisocyanate, which is a constituent component, so it does not bleed into molded products etc. It has excellent physical properties.

Further, a polyurethane dispersion using the dispersant can be used as a coating material or adhesive as a dispersion solution. The polyurethane powder obtained by the present invention has a wide range of uses, including various molding materials, powder coatings, various modifiers, and fillers.

Claims (1)

[Claims] 1. A polyol obtained by adding an unsaturated bond-containing glycol or an unsaturated group-containing dicarboxylic acid to a reaction between a glycol and a dibasic acid, or a polyester polyol or polycarbonate polyol and an unsaturated bond-containing dicarboxylic acid. It consists of a polyol obtained by reacting with
100 parts by weight of a polyol having 1 to 10 moles of unsaturated bonds and 2 active hydrogen groups per molecule, and 20 to 400 parts of an ethylenically unsaturated monomer having a side chain consisting of a hydrocarbon group having 6 or more carbon atoms. 1. A method for producing a dispersant for non-aqueous dispersion polymerization for producing polyurethane, which comprises dropping a mixed solution consisting of parts by weight and 0.4 to 8.1 parts by weight of a reaction initiator and then causing a reaction.