JP5282793B2 - Emulsion - Google Patents

Description

  The present invention relates to an emulsion. More particularly, it relates to an emulsion of perfluoropolyether oil or perfluorocarbon compound.

Polyfluoroalkylphosphonic acid esters are widely used as raw materials for synthesizing release agents. The mold release performance when used as a mold release agent is most easily manifested in compounds having 8 to 12 carbon atoms in the perfluoroalkyl group, and is particularly a C ₈ telomer compound.
CF ₃ (CF ₂ ) ₇ CH ₂ CH ₂ P (O) (OC ₂ H ₅ ) ₂
However, it is preferably used for this kind of application (see Patent Documents 1 to 4).

  By the way, it has been reported that a telomer compound having a perfluoroalkyl group having 8 to 12 carbon atoms is biodegraded in the environment and converted into a compound having a relatively high bioaccumulation property and environmental concentration property. There are concerns about exposure to the environment, waste, release to the environment from treated substrates, and diffusion. In addition, compounds having a perfluoroalkyl group with 14 or more carbon atoms are very difficult to handle because of their physical and chemical properties, and are rarely used in practice.

  Furthermore, telomer compounds having a perfluoroalkyl group having 8 or more carbon atoms cannot avoid the generation or contamination of perfluorooctanoic acids having high bioaccumulation potential in the production process. For this reason, manufacturers of such telomer compounds are proceeding withdrawing from the production or replacing them with compounds having a perfluoroalkyl group having 6 or less carbon atoms.

  On the other hand, in the compound having 6 or less carbon atoms in the perfluoroalkyl group, the orientation on the surface of the treated substrate is remarkably lowered, and the melting point, the glass transition point Tg, etc. are remarkably lower than the compound having 8 carbon atoms. It will be greatly affected by environmental conditions such as temperature, humidity, stress, and contact with organic solvents. Therefore, the required sufficient performance cannot be obtained, and the durability is also affected.

  An aqueous release agent composition in which an ammonium salt or amine salt of perfluoroalkylalkylphosphonic acid and a polyether-modified organopolysiloxane are dissolved or dispersed in water has also been proposed (see Patent Document 5). Perfluorooctyl ethyl phosphonate is used, and it is said that a transparent release agent solution is obtained.

  Perfluoropolyether oils widely used as water and oil repellents and lubricants are excellent in water and oil repellency and lubricity, but lack compatibility with other compounds. Is limited.

  Perfluoropolyether oil is also used as a leather treatment agent by adding a greasing agent to the perfluoropolyether oil (see Patent Document 6). As the greasing agent, in a general description thereof, a phosphonic acid derivative having a fluoroalkyl group, a fluoroalkenyl group or a fluoroether group or an ammonium salt, an alkali metal salt or an alkaline earth metal salt thereof is used. However, the use ratio of the greasing agent is 10 to 0.5, preferably 5 to 1, with respect to the fluorinated oil.

  Fluorine oil and greasing agent used in such a weight ratio are said to be tanned leather treated in the greasing process by a leather treating agent usually contained in the form of an emulsion. In the processing agent to be used, the average particle size of the emulsion is reduced in proportion to the amount of emulsifier used, and the stability over time is ensured. The product becomes hydrophilic and water repellency is lowered, and it is not possible to avoid a drop in mold release performance when this is used as a mold release agent (see Comparative Examples below).

  The present applicant has previously proposed a method for producing perfluoroalkylethylphosphonic acid by thermally decomposing or hydrolyzing perfluoroalkylethylphosphonic acid diester (see Patent Document 7). Since the perfluoroalkylethylphosphonic acid obtained here does not dissolve in an aqueous medium such as water, it cannot be used as an aqueous emulsifier solution.

On the other hand, perfluoropolyether oils, which enables use as a surface treatment agent by emulsifying, water- and oil-repellent, and can be applied to the release agent or the like. Moreover, by emulsifying, it can be applied to medical use and cosmetic use. For example, by blending into cosmetics, for example, by blending with lipstick, the effect of preventing the lipstick from being transferred to others is exhibited.

However, in an emulsion as described in Patent Document 6, since a large excess of a greasing agent (ammonium salt or metal salt of perfluoroalkylalkylphosphonic acid) is used in combination with fluorine-based oil, leather is used. Even if it is suitable as a treatment method, when it is applied to an emulsion of perfluoropolyether oil , the properties of these compounds themselves are not sufficiently exhibited.

Japanese Examined Patent Publication No. 2-45572 Japanese Patent Publication No. 3-78244 Japanese Patent Publication No. 4-4923 Japanese Patent Publication No. 4-11366 Japanese Patent Publication No. 8-5063 Japanese Patent No. 3077231 JP 58-210096 JP 2000-72601 A

An object of the present invention is to provide a compound having a perfluoroalkyl group having a carbon number of 6 or less, which is said to have low bioaccumulation, and having an emulsifying performance comparable to ammonium pentadecafluorooctanoate having excellent emulsifying performance. It was used as is to provide an emulsion of perfluoropolyether oils.

The object of the present invention is to provide a general formula
RfO [CF (CF ₃ ) CF ₂ O] _m Rf ′ (I)
(Wherein, Rf, Rf 'is a perfluoroalkyl lower alkyl group of 1 to 5 carbon atoms, m is an integer of 2 to 200) with respect to the perfluoropolyether oil 100 parts by weight represented by the general as an emulsifier formula
C _n F _{2n + 1} CH ₂ CH ₂ P (O) (OM ¹ ) (OM ² ) (II)
(Wherein, M ¹ is a hydrogen atom, or an ammonium salt, M ² is ammonium salt, n represents a is an integer from 1 to 6) the perfluoroalkylethyl phosphonic acid ammonium salt 0.01 to 30 parts by weight represented by Achieved with the emulsion formed.

The ammonium perfluoroalkylethylphosphonate emulsifier used in the present invention is a compound having a perfluoroalkyl group having a carbon number of 6 or less, which is said to have low bioaccumulation, and is an ammonium pentadecafluorooctanoate having excellent emulsifying performance. has an emulsifying capability comparable to emulsion consisting of an aqueous solution or an organic solvent solution and perfluoropolyether oil of the emulsifier, it is possible to form a stable emulsion. Its emulsification stability is well maintained even after standing at room temperature or at 40 ° C. for 1 month.

Emulsions with perfluoropolyether oils are suitably used for applications such as surface treatment agents, mold release agents, anti-tacking agents, cosmetics, etc. while maintaining good emulsion stability .

It is a graph which shows the relationship between the emulsifier density | concentration obtained in Example 1 (1) and Reference Example 1, and surface tension.

Perfluoroalkylethylphosphonic acid ammonium salt used as emulsifier
C _n F _{2n + 1} CH ₂ CH ₂ P (O) (OM ¹ ) (OM ² ) (II)
Perfluoroalkylethylphosphonic acid described in Patent Document 7
C _n F _{2n + 1} CH ₂ CH ₂ P (O) (OH) ₂ (III)
To be obtained by reacting an aqueous ammonia solution.

Ammonia forms a mono-salt when used in equimolar amounts relative to perfluoroalkylethylphosphonic acid, and forms a di-salt when used in double molar amounts. Generally, it is used in the required theoretical number of moles or more, and when used in an equimolar amount or more and less than twice the molar amount, a mixture of a mono salt and a di salt is formed.

The perfluoroalkylethylphosphonic acid ammonium salt is used as an aqueous solution dissolved in an aqueous medium which is water or an aqueous organic solvent solution or an organic solvent solution dissolved in an organic solvent. Examples of the organic solvent include alcohols such as methanol, ethanol, and isopropanol, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aprotic polarities such as acetonitrile, dimethylformamide, diethylformamide, dimethylacetamide, and N-methyl-2-pyrrolidone. A solvent is used.

The emulsifying ability of perfluoroalkylethylphosphonic acid ammonium salt is, for example, in the case of 2- (perfluorohexyl) ethylphosphonic acid ammonium aqueous solution, the critical micelle concentration [CMC] is found at an emulsifier concentration of about 0.8% by weight. Shows a constant low surface tension up to about 2.0% by weight.

An aqueous solution or an organic solvent solution of the emulsifier is added to the perfluoropolyether oil in an amount of about 0.01 to 30 parts by weight, preferably about 0.1 to 15 parts by weight, based on 100 parts by weight of the perfluoropolyether oil. And emulsified to form a perfluoropolyether oil emulsion. When the emulsifier is used in a proportion higher than this, the characteristics of the perfluoropolyether oil itself are not sufficiently exhibited. The emulsification treatment is performed by pre-emulsification using a homogenizer or the like at a rotational speed of about 500 to 10,000 rpm, and further emulsified at a pressure of about 100 to 800 kgf / cm ² (about 9.8 to 78.4 MPa) using a high-pressure homogenizer. Done.

The perfluoropolyether oil to be emulsified has a general formula
RfO [CF (CF ₃ ) CF ₂ O] _m Rf ′ (I)
The one represented by is used. Here, Rf and Rf ′ are perfluoro lower alkyl groups having 1 to 5 carbon atoms such as perfluoromethyl group and perfluoroethyl group, and m is 2 to 200. Further, those having a number average molecular weight Mn of about 300 to 50000, preferably about 500 to 20000 are used.

This by completely fluorinating the precursor produced by photooxidation polymerization of hexafluoropropene, or a hexafluoropropene oxide was subjected to anionic polymerization in the presence of cesium fluoride catalyst, resulting terminal -CF (CF ₃ ) It can be obtained by treating an acid fluoride compound having a COF group with a fluorine gas.

Perfluoropolyether oil [I] can be used with any value of kinematic viscosity, but as a lubricant, it is preferably ⁵ to 2000 mm ² / sec (40 ° C.), considering use under high temperature conditions. Is 100 to 1500 mm ² / sec (40 ° C.). In other words, those with about 5 mm ² / sec or less have a large evaporation amount and do not satisfy the condition of an evaporation amount of 1.5% or less stipulated in the JIS rolling bearing grease type 3 which is a standard for heat-resistant grease. Also, those with a kinematic viscosity of 2000 mm ² / sec or higher have a pour point (JIS K-2283) of 10 ° C or higher, and the bearing does not rotate at low temperature startup in the normal method. There is a need to.

  In addition, the perfluoropolyether oil emulsion is an aqueous solution or an organic solvent so that the solid content (perfluoropolyether oil) concentration is about 0.01 to 30% by weight, preferably about 0.05 to 10% by weight. When used as an aqueous solution or an organic solvent solution diluted with 1, it can be used as a surface treatment agent such as a water / oil repellent and a release agent while maintaining good emulsification stability. When it is used as a mold release agent, it is applied to a molding die surface, and when it is applied to a substrate such as a molded product, it is used as an anti-sticking agent.

  Next, the present invention will be described with reference to examples.

Example 1
(1) A 200 ml capacity equipped with a stirrer and a dripping device was charged into a reactor while keeping 50 g of water heated to 40 ° C. while keeping 2- (perfluorohexyl) ethylphosphonic acid (Unimatec CHEMINOX FHP). After adding 2 g (11.7 mmol) of 2-OH), 20.5 g (16.9 mmol) of an aqueous ammonia solution having a concentration of 1.4% by weight was added, and stirring was continued for 1 hour to carry out a neutralization reaction. As a result, an aqueous solution of 2- (perfluorohexyl) ethylphosphonic acid ammonium salt having a pH of 8 (active ingredient concentration: 6.9% by weight) was obtained [Emulsifier aqueous solution I].

  This aqueous emulsifier solution I was added little by little in water, and the surface tension of the aqueous solution was measured. As indicated by a circle in the graph of FIG. 1, the critical micelle concentration [CMC] was 0.8% by weight and the minimum surface tension was 17 mN / m. The surface tension was measured at 20 ° C. by the maximum bubble method using a SITA dynamic surface tension meter.

  When stirring for 1 hour without adding an aqueous ammonia solution to 2- (perfluorohexyl) ethylphosphonic acid, the added 2- (perfluorohexyl) ethylphosphonic acid was separated without dissolving in water, An aqueous solution was not obtained.

(2) In a 1,000 ml reactor equipped with a stirrer and a dropping device, 182 g of water heated to 40 ° C. was charged while being kept therein, and 218 g of an emulsifier aqueous solution I and a general formula
C ₃ F ₇ O [CF (CF ₃ ) CF ₂ O] _m C ₂ F ₅ (m: 2 to 100)
After adding 100 g (overall amount 500 g) of perfluoropolyether oil (NOK Kluber product BARRIERTA J 25 FLUID; kinematic viscosity (40 ° C.) 25 mm ² / sec) represented by 2 at a rotational speed of 3000 rpm using a homogenizer Pre-emulsification for 5 minutes, and further emulsified with a high pressure homogenizer (manufactured by Nippon Seiki Co., Ltd.) at a pressure of 600 kgf / cm ² (58.8 MPa), and perfluoropolyether oil emulsion A (per 100 parts by weight of perfluoropolyether oil) As a result, 485 g (97% recovery rate) of 15.0 parts by weight of perfluoroalkylethylphosphonic acid ammonium salt was obtained.

  The average particle diameter of the obtained perfluoropolyether oil emulsion A was 151 nm. When the average particle diameter of this emulsion A after standing at room temperature and at 40 ° C. for 1 month was measured, values of 153 nm and 155 nm were obtained, respectively, indicating that stable emulsions were formed. confirmed. The average particle size was measured by a dynamic light scattering method using a Nikkiso Microdrug Particle Size Distribution Analyzer UPA150.

  When the amount of water was changed to 385 g, and when 15 g of 2- (perfluorohexyl) ethylphosphonic acid was used in place of the emulsifier aqueous solution I, the liquid mixture immediately caused liquid-liquid separation, and no emulsion was formed. .

Reference example 1
In Example 1 (1), instead of 2- (perfluorohexyl) ethylphosphonic acid and an aqueous ammonia solution, 5 g of pentadecafluorooctanoic acid ammonium salt (Diemco product F-top EF204) was used. 9.1 wt%) was obtained [Emulsifier aqueous solution II].

  When the surface tension of this aqueous emulsifier II was measured in the same manner, as shown by the black square in the graph of FIG. 1, its CMC was 0.8% by weight and the minimum surface tension was 18 mN / m.

Example 2
In Example 1 (2), the same amount (100 g) of perfluoropolyether oil represented by the same general formula (NOK Kluber product BARRIERTA J 100 FLUID; kinematic viscosity (40 ° C.) 95 mm ² / sec) was used (total) 500 g), and 486 g of perfluoropolyether oil emulsion B (recovery rate 97%) was obtained. The average particle size of this emulsion B was 131 nm, the average particle size after one month at room temperature was 136 nm, the average particle size after one month at 40 ° C. was 140 nm, and it was confirmed that a stable emulsion was formed. .

Example 3
In Example 1 (2), the same amount (100 g) of perfluoropolyether oil represented by the same general formula (NOK Kluber product BARRIERTA J 400 FLUID; kinematic viscosity (40 ° C.) 390 mm ² / sec) was used (total) 500 g) and 485 g of Perfluoropolyether oil emulsion C (97% recovery rate). The average particle size of this emulsion C is 145 nm, the average particle size after one month at room temperature is 146 nm, the average particle size after one month at 40 ° C. is 150 nm, and it is confirmed that a relatively stable emulsion is formed. It was done.

Reference example 2
In Example 2, 165 g of an emulsifier aqueous solution II which is an aqueous solution of pentadecafluorooctanoic acid ammonium salt is used in place of the emulsifier aqueous solution I, and the amount of water is changed to 235 g (total amount 500 g). 482 g of emulsion D (96% recovery rate) was obtained. The average particle size of this emulsion D was 140 nm, the average particle size after one month at room temperature was 143 nm, the average particle size after one month at 40 ° C. was 145 nm, and a stable emulsion was formed.

Comparative Example 1
(1) In Example 1 (1), 1.71 g (16.9 mmol) of triethylamine was used instead of 20.5 g (16.9 mmol) of an aqueous ammonia solution having a concentration of 1.4% by weight, and 2- (perfluorohexyl) ethylphosphonic acid triethylamine salt was used. (Emulsifier aqueous solution III) was obtained.

  When the critical micelle concentration [CMC] and the minimum surface tension of this aqueous emulsifier solution III were measured in the same manner, values of 1.2% by weight and 27.7 mN / m were obtained, respectively.

(2) In Example 1 (2), the amount of water heated to 40 ° C. was changed to 231 g, the amount of the emulsifier aqueous solution III used instead of the emulsifier aqueous solution I was changed to 169 g, and the perfluoropolyether oil (BARRIERTA J 100 FLUID) The amount and amount were changed to 100 g (total amount 500 g), respectively, and 483 g (97% recovery rate) of perfluoropolyether oil emulsion E was obtained.

The average particle diameter of the obtained perfluoropolyether oil emulsion E was 405 nm. Further, it was confirmed that when this emulsion E was allowed to stand at room temperature and at 40 ° C. for 1 month, a precipitate was formed and separated.

Example 4
A release agent emulsion was prepared by adding 2.5 parts by weight of perfluoropolyether oil emulsion A to 97.5 parts by weight of ion-exchanged water while stirring.

A mold release test at the time of molding urethane rubber using this mold release agent emulsion was carried out as follows.
An aluminum cup having a diameter of 45 mm and a depth of 50 mm was used as a mold, the mold was heated to 80 ° C., a release agent was applied, and the mold was dried at 80 ° C. In this release agent coating mold, 100 parts by weight of urethane prepolymer (Japan polyurethane product Coronate 4090) heated to 80 ° C and methylene bis (o-chloroaniline) curing agent (Ihara Chemical product Iharacamine) heated to 120 ° C MT) 10 g of a mixture of 12.8 parts by weight was injected and cured at 120 ° C. for 1 hour.

  Before curing, a hook for taking out the cured molded product is installed in the center of the injection part, and when the load when removing the molded product from the mold by pulling the hook after curing is determined with a spring balance located above, it is 8N The value (release performance) was obtained. When the number of times the mold can be released with a release load of 50 N or less was measured after first applying the mold release agent, a value of 9 times (mold release life) was obtained.

  On the other hand, the release performance and release life were measured without applying the release agent emulsion, but the molded product did not peel off from the mold and could not be measured. Therefore, the release life was 0 times. there were.

Comparative Example 2
(1) In Example 1 (1), the amount of 2- (perfluorohexyl) ethylphosphonic acid was changed to 10 g (23.4 mmol), and the amount of aqueous ammonia solution having a concentration of 1.4% by weight was changed to 40 g (32.9 mmol). An aqueous solution thereof (active ingredient concentration 10.0% by weight) was obtained [emulsifier aqueous solution IV].

(2) In Example 1 (2), 250 g of emulsifier aqueous solution IV, 5 g of perfluoropolyether oil (BARRIERTA J 100 FLUID) and 245 g of water (over 500 g in total) were used, and 486 g of perfluoropolyether oil emulsion F was used. (97% recovery). The average particle size of this emulsion F is 61 nm, the average particle size after one month at room temperature is 65 nm, the average particle size after one month at 40 ° C. is 66 nm, and it is confirmed that a relatively stable emulsion is formed. It was done.

(3) In Example 4 , instead of perfluoropolyether oil emulsion A, a release agent emulsion was prepared using the same amount (2.5 parts by weight) of perfluoropolyether oil emulsion F , and then using that as a urethane When a mold release test at the time of rubber molding was performed, the measurement result was a mold release performance of 20 N and a mold release life of 2 times.

Claims (3)

General formula
RfO [CF (CF ₃ ) CF ₂ O] _m Rf ′ (I)
(Wherein Rf and Rf ′ are perfluoro lower alkyl groups having 1 to 5 carbon atoms, and m is an integer of 2 to 200). formula
C _n F _{2n + 1} CH ₂ CH ₂ P (O) (OM ¹ ) (OM ² ) (II)
(Wherein M ¹ is a hydrogen atom or an ammonium salt, M ² is an ammonium salt, and n is an integer of 1 to 6) 0.01 to 30 parts by weight of perfluoroalkylethylphosphonic acid ammonium salt Emulsion formed using.   The emulsion according to claim 1, wherein the emulsifier is used as an aqueous solution or an organic solvent solution. The emulsion according to claim 1, which is prepared as an aqueous solution having a solid content of 0.01 to 30% by weight.

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