JPH0237952B2 - ABURABAITAIKOKOKEIBUNHISUIKEIDEISUPAAJONNOSEIZOHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a non-aqueous dispersion with a high solids content in an oil medium, and more specifically, a non-aqueous dispersion using an alkyd resin as a dispersion stabilizer is prepared in advance, and then a non-aqueous dispersion with an oil medium The present invention relates to a method for producing an oil vehicle high solids content non-aqueous dispersion comprising adding components to replace the organic liquid in the dispersion with an oil vehicle component.

It has been known that non-aqueous dispersions, when mixed with other coating resins, contribute to improving the drying properties and other coating properties of coating films obtained therefrom. However, since this non-aqueous dispersion contains an organic solvent as a dispersion medium, its solid content cannot exceed 70% by weight at most. In response to this, there has recently been a strong demand for reducing the amount of organic solvents used in paints, in other words, increasing the solidity of paints, in order to conserve resources and prevent air pollution.This also applies to non-aqueous dispersion paints. This is not an exception.

However, various methods for obtaining non-aqueous dispersions with high solid content have been proposed in the past. There is a method of polymerizing an acrylic monomer in a medium to form polymer particles stably dispersed in an oil medium (for example, Japanese Patent Publication No. 56-41641,
(Refer to Japanese Patent Application Laid-Open No. 157483/1983).

However, in the synthesis of non-aqueous dispersion using the conventional method described above, since the acrylic monomer is polymerized in an oil medium, oxidative polymerization and thermal polymerization of the oil medium itself are unavoidable, making it difficult to produce a stable dispersion. . In addition, strict temperature control is necessary to maintain an appropriate reaction temperature during the synthesis of non-aqueous dispersion, and if this temperature control is not sufficient, for example, if the reaction temperature is too high, the oil medium itself may As thermal polymerization progresses, the non-aqueous dispersion thickens and becomes a gel.On the other hand, if the reaction temperature is too low, the polymerization of the acrylic monomer does not proceed sufficiently, leaving a large amount of unreacted monomer in the non-aqueous dispersion. However, there are still some drawbacks such as residual defects, and there are still problems that need to be solved in manufacturing.

In view of the above-mentioned problems, the present inventors have developed a stable high-solids oil medium that prevents polymerization of the oil medium, can be easily produced without requiring special temperature control, and does not leave any unreacted monomers. The present invention was completed as a result of extensive research aimed at obtaining a non-aqueous dispersion.

Thus, according to the invention, in the presence of an oil with an oil length of 20 to 70 and/or a fatty acid-modified alkyd resin, the monomer is soluble but the polymer formed is insoluble in an organic liquid. Saturated vinyl monomers are dispersion polymerized to form a non-aqueous polymer dispersion, and the dispersion is then supplemented with at least one oil component selected from animal oils, vegetable oils, thermally polymerized oils thereof, or air-blown oils. A) and a long oil alkyd resin (B) with an oil length of 65 to 80 and a viscosity of Z ₅ or less (measured with a Gardner viscometer at 25°C with a solid content of 90%) are (A) / (B) = 100 /
Production of an oil medium high solid content non-aqueous dispersion characterized by mixing oil medium components in a ratio of 0 to 50/50 (weight ratio) and then heating and distilling off the organic liquid in the mixture. A method is provided.

The oil and/or fatty acid-modified alkyd resin with an oil length of 20 to 70 used as a dispersion stabilizer in the present invention includes (anhydrous) phthalic acid, isophthalic acid, terephthalic acid, dimethylisophthalic acid,
Polybasic acids such as dimethyl terephthalic acid, tetrahydrophthalic acid (anhydride), hexahydrophthalic acid (anhydrous), adipic acid, maleic acid (anhydride), azelaic acid, and succinic acid (anhydride) are used, and ethylene glycol is used as the alcohol component. , propylene glycol, diethylene glycol, triethylene glycol, butylene glycol, 1,5-pentanediol, neopentyl alcohol, 1,
Polyhydric compounds such as 6-hexanediol, 2,5-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, dipropylene glycol, trimethylolethane, trimethylolpropane, glycerin, diglycerin, pentaerythritol, etc. Alcohol is used, and as modified oils, animal oils ranging from non-drying oils to drying oils, vegetable oils and their fatty acids, such as coconut oil, palm kernel oil, castor oil, rice bran oil, soybean oil, safflower oil, dehydrated Castor oil, linseed oil, tung oil, fish oil, coconut oil fatty acids, castor oil fatty acids, rice bran oil fatty acids, cottonseed oil fatty acids, soybean oil fatty acids, tall oil fatty acids, safflower oil fatty acids, dehydrated castor oil fatty acids, linseed oil fatty acids, fish oil Manufactured using fatty acids, etc. The alkyd resin can be produced according to a conventional method known per se, for example, by subjecting each component to a dehydration condensation reaction at about 150 to about 250°C for about 3 to about 10 hours.

The oil length of the alkyd resin thus obtained is 20 to 70.
The reason why the oil length should be limited to this range is that oil lengths outside this range do not function sufficiently as a dispersion stabilizer, and obtaining a stable dispersion is subject to restrictions on the composition of the core. Furthermore, it has the disadvantage that its compatibility with other resins is poor, which significantly limits its range of use.

Examples of unsaturated vinyl monomers used as dispersed polymer components include vinyl aromatic compounds such as styrene and vinyltoluene; methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, i-butyl methacrylate, and t-butyl methacrylate. , 2-ethylhexyl methacrylate, methyl acrylate, ethyl acrylate, n _- butyl acrylate, i-butyl acrylate, t-butyl acrylate, 2-ethylhexyl acrylate, etc. _C1-12 alkyl ester of acrylic acid or methacrylic acid; 2-hydroxy Ethyl acrylate, 2
-Hydroxyalkyl esters of acrylic acid or methacrylic acid such as hydroxymethacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate; glycidyl acrylate, glycidyl methacrylate; α,β-ethylenically unsaturated acids such as acrylic acid, methacrylic acid, maleic acid; others Monomers such as acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl acetate, etc. are used, and these monomers can be used singly or in combination of two or more.

The dispersion medium used when dispersing and polymerizing unsaturated vinyl monomers using the above-mentioned alkyd resin as a dispersion stabilizer is an organic solvent in which the monomer is soluble but the formed polymer is substantially insoluble. It is liquid and has a boiling point of 150°C or less, preferably 120°C or less, so that it can be easily replaced with the oil medium component.
Medium boiling organic solvents are used.

Examples of the organic solvent include methanol, ethanol, isopropyl alcohol, sec-butyl alcohol, methylisobutylcarbinol,
Alcohol solvents such as isobutyl alcohol;
Ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone; aromatic solvents such as toluene and xylene; and aliphatic hydrocarbon solvents such as n-pentane, n-hexane, n-heptane, and n-octane are used. These are 1 type or 2
Can be used in combination of more than one species.

As the method for producing the non-aqueous polymer dispersion in the present invention, any conventionally known method may be used,
For example, use a reaction vessel equipped with a stirring device, a heating device, a thermometer, a solvent cooling tube, a reflux device, a monomer dropping device, and a pressure reduction device, and add an alkyd resin as a dispersion stabilizer to a solid content of 10 to 70% by weight. The unsaturated vinyl monomer and the radical polymerization initiator are dissolved in the above-mentioned organic solvent and heated while stirring, and when the solvent reaches a reflux temperature, the unsaturated vinyl monomer and the radical polymerization initiator are heated for about 1 to 6 hours. The mixture is synthesized by adding the mixture and reacting for about 0.5 to 2 hours. The reaction temperature depends on the solvent used, but is usually between 50 and 150℃.
It is ℃.

The mixing ratio of alkyd resin and unsaturated vinyl monomer in the above reaction is usually 10/90 to 10/90 by weight.
It is in the range of 70/30, preferably 20/80 to 60/40.

In addition, the radical polymerization initiators used include benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide, t-
Peroxide catalysts such as -butylperoxy-2-ethylhexanoate and t-butylperoxybenzoate, and azo catalysts such as azobisdimethylvaleronitrile and azobisisobutylnitrile are typically used.

An oil vehicle component is then added to the non-aqueous polymer dispersion thus formed. The oil medium components include _at least one oil component (A) selected from animal oils, vegetable oils, thermally polymerized oils thereof, or air-blown oils; Ultra-long oil-based alkyd resin (B) (measured at a total temperature of 25℃)
is (A)/(B)=100/0 to 50/50, preferably 90/10
The ratio is ~70/30 (weight ratio).

The above oil component (A) is the same as that used as the modified oil of the alkyd resin used as a dispersion stabilizer, and has a viscosity of M or less (Gardner viscometer 25 ° C
(measured in ) can be used. Also,
Ultra-long oil-based alkyd resin (B) also has an oil length of 65 to 80 and a viscosity.
Any known alkyd resin having the same composition as the alkyd resin used as a dispersion stabilizer can be used as long as Z is ₅ or less.

The oil medium component added to the non-aqueous polymer dispersion may consist of only the oil component (A), but it can be obtained by adding an ultra-long oil-based alkyd resin (B) to the component (A). The drying properties and physical properties of the coating film can be improved. If the oil length of component (B) is outside the above range, the expected drying properties and physical properties of the coating film cannot be obtained. Furthermore, if the viscosity of component (B) exceeds _Z5 , the viscosity of the highly solidified dispersion becomes too high to be put to practical use, and as a result, it becomes difficult to achieve high solidity. Furthermore, even if component (B) exceeds 50% by weight of the oil medium component, the viscosity increases and it becomes difficult to achieve high solidity.

The non-aqueous polymer dispersion to which the oil medium component has been added is then heated to distill off the organic solvent it contains, thereby completely replacing the organic solvent with the oil medium, resulting in almost 100% of the desired content. An oil-based non-aqueous dispersion having a solid content is obtained. When the organic solvent is distilled off from the above non-aqueous polymer dispersion by heating, the temperature is reduced under reduced pressure, e.g. 1 mmHg to 760 mmHg, to avoid oxidative polymerization and thermal polymerization of the oil medium component.
It is advantageous to work at temperatures between 0°C and 110°C.

The time required for producing the oil-based non-aqueous dispersion of the present invention ranges from about 5 to about 15 hours.
And the temperature is about 0 to about 150℃ (polymerization reaction temperature is about 50℃
to about 150°C).

The method for producing a nonaqueous oil-based dispersion according to the present invention has the following advantages over conventional methods.

Since the reaction temperature is the reflux temperature of the organic solvent, the reaction temperature can be easily controlled and an oil medium non-aqueous dispersion of constant quality can be obtained. After synthesizing the non-aqueous polymer dispersion, the organic solvent and the oil medium component are replaced, so the possibility of thermal polymerization of the oil medium component is extremely reduced, and by reducing the pressure, oxidative polymerization does not occur, and the oil medium component is Since the components are not altered, it is possible to obtain an oil-based nonaqueous dispersion having a stable dispersion state.

Furthermore, by removing the organic solvent under reduced pressure, unreacted unsaturated vinyl monomers can also be removed at the same time as the organic solvent, resulting in a high quality oil-based non-aqueous dispersion.

Furthermore, by mixing the oil-based non-aqueous dispersion obtained by the present invention with other paint resins, the solid content of the paint can be increased, and the drying properties and physical properties of the paint film can be significantly improved. effective.

Hereinafter, the present invention will be illustrated in more detail with reference to Examples. Note that % indicates weight %.

Example 1 A reaction vessel was charged with 300 g of n-heptane, 150 g of n-butyl alcohol, and 100 g of xylene, and 180 g of a soybean oil fatty acid modified alkyd resin with an oil length of 60 and an acid value of 5.0 was added thereto and dissolved, and then the solvent was refluxed. heated to temperature (80-85 °C). Next, 120g of methyl acrylate, 80g of methyl methacrylate,
Acrylonitrile 80g, styrene 70g, hydroxypropyl methacrylate 60g and acrylic acid 10g
azobisisobutylnitrile to the monomer mixture of
A solution of 6.0 g was prepared in advance in a dropping device, and was dropped into the dispersion stabilizer solution over a period of 3 hours. One hour after the completion of the dropping, a solution of 4.0 g of azobisisobutylnitrile dissolved in 50 g of xylene was added dropwise over 1 hour, and
The reaction was allowed to continue for an hour. Next, 600 g of dehydrated castor oil was added to the obtained non-aqueous polymer dispersion, and the mixture was heated for 50 minutes under reduced pressure (760 mmHg to 1 mmHg), and all the organic solvent and unreacted monomers were removed. A stable oil-based non-aqueous dispersion with a solid content of 100% and a viscosity of X (Gardner viscometer, 25° C. or lower) was obtained.

Example 2 A reaction vessel was charged with 350 g of n-heptane and 200 g of n-butyl alcohol, and linseed oil fatty acid modified alkyd resin 120 with an oil length of 60 and an acid value of 10.5 was added to the reactor.
g was added and dissolved, and then heated to the reflux temperature of the solvent. Next, 130g of methyl acrylate, 100g of methyl methacrylate, and 100g of acrylonitrile.
A solution of 6.6 g of azobisisobutylnitrile dissolved in a monomer mixture of 70 g of styrene, 70 g of hydroxypropyl methacrylate, and 10 g of acrylic acid was prepared in advance in a dropping device, and was added to the dispersion stabilizer solution over 3.5 hours. dripped. 1 hour after the completion of dropping, add azobisisobutylnitrile.
A solution of 4.4 g dissolved in 50 g of toluene was added dropwise over 1 hour, and the reaction was continued for an additional 2 hours.
Then, linseed oil was added to the obtained non-aqueous polymer dispersion.
360 g and 40 g of thermally polymerized linseed oil were added, and the mixture was heated under reduced pressure (760 to 1 mmHg) for 40 minutes. All organic solvents and unreacted monomers were removed, and the solid content and viscosity were 100%. A stable oil-based non-aqueous dispersion of Z was obtained.

Example 3 300 g of n-heptane, 200 g of n-butyl alcohol, and 50 g of xylene were placed in a reaction vessel, and 210 g of a soybean oil fatty acid modified alkyd resin with an oil length of 55 and an acid value of 5.2 was added thereto and dissolved, and then the solvent was refluxed. heated to temperature. Then methyl acrylate
110g, acrylonitrile 80g, hydroxypropyl methacrylate 60g, methyl methacrylate
A solution prepared by dissolving 5.4 g of azobisisobutylnitrile in a monomer mixture of 70 g of styrene, 60 g of styrene, and 10 g of acrylic acid was prepared in advance in a dropping device, and was dropped into the dispersion stabilizer solution over 2.5 hours.
1.5 hours after the completion of the dropwise addition, a solution of 3.6 g of azobisisobutylnitrile dissolved in 50.0 g of xylene was added dropwise over 1 hour, and the reaction was continued for an additional 3 hours. Next, 480 g of linseed oil and 120 g of a linseed oil fatty acid modified alkyd resin having an oil length of 80 and an acid value of 15.3 were added to the obtained non-aqueous polymer dispersion, and the mixture was heated under reduced pressure (760 to 1 mmHg) for 60 minutes. All organic solvents and unreacted monomers were removed, and a stable oil-based nonaqueous dispersion having a solid content of 100% and a viscosity of Y was obtained.

Claims (1)

[Claims] 1 Dispersion of unsaturated vinyl monomers in an organic liquid in which the monomers are soluble but the polymer formed is insoluble in the presence of an oil with an oil length of 20 to 70 and/or a fatty acid-modified alkyd resin. Polymerization is performed to form a non-aqueous polymer dispersion, and the dispersion is then supplemented with at least one oil component (A) selected from animal oils, vegetable oils, thermally polymerized oils thereof, or air-blown oils, and an oil with an oil length of 65 to 65. 80 and viscosity Z ₅ or less (Gardner viscometer 25℃ at 90% solids)
) long oil alkyd resin (B) is (A)/(B)=
An oil medium high solid content nonaqueous dispersion characterized by mixing oil medium components in a ratio of 100/0 to 50/50 (weight ratio) and then heating and distilling off the organic liquid in the mixture. manufacturing method.