KR102120447B1 - The method for preparation of polyvinylidene fluoride nanoparticle using poly(ethylene glycol)s and the polyvinylidene fluoride nanoparticle thereby - Google Patents

Abstract

Preparing a mixed solution by mixing a radical initiator, distilled water, and a compound represented by the following Chemical Formula 1 in one aspect of the present invention (step 1); And adding vinylidene fluoride (VDF) to the mixed solution prepared in step 1 (step 2); providing a method of manufacturing polyvinylidene fluoride (PVDF) nanoparticles do. The method for producing polyvinylidene fluoride nanoparticles according to the present invention is a process using an existing ammonium-based surfactant (ammonium perfluorinated octanoate, APFO) having 8 carbon fluoride by using a polyethylene glycol-based compound for emulsion polymerization. Not only can it be used in a much smaller amount, the compound used in the present invention has an effect that can reduce the manufacturing cost of polyvinylidene fluoride as well as APFO replacement because there is little human accumulation and toxicity.

Description

The method for preparation of polyvinylidene fluoride nanoparticles using poly(ethylene glycol)s and the polyvinylidene fluoride nanoparticles by the method for preparing polyvinylidene fluoride nanoparticles using polyethylene glycol

The present invention relates to a method for producing polyvinylidene fluoride nanoparticles using polyethylene glycol and a polyvinylidene fluoride nanoparticle prepared accordingly.

The organic fluorine polymer material exhibits unique properties different from other hydrocarbon-based polymer materials such as low energy surface properties, heat resistance, stability, and chemical resistance. For this reason, it has been used as a key material for achieving high functionalization, high performance and high added value of products in the national key industries such as the electric and electronic industry, semiconductor industry, display industry, and automobile industry.

The global market for organic fluorine polymer materials is 265,000 MT in 2011 and has a market of more than about 7 trillion won, of which the market related to polyvinylidene fluoride (PVDF) is about 24.5 including fluorine rubber. % (Market and Market Analysis, 2012).

In addition, the domestic fluorine polymer market is about 20,000 MT, and polyvinylidene fluoride is dependent on imports. It has a market of 100 billion won with about 3,000 MT (June 30, 2011, Chemical Journal).

As one of the most important experimental parameters in emulsion polymerization, ammonium perfluorinated octanoate (APFO), which has 8 carbon fluoride as a surfactant, has been widely used for polymerization of vinylidene fluoride. However, APFO-based substances accumulate in human blood and have been defined as dangerous substances that cause carcinogens and pregnancy disorders in animal experiments.

In particular, as the length of carbon fluoride increases to 8 or more, the risk has been investigated to rise sharply. Accordingly, agreements have been reached between fluorine polymer manufacturers to reduce APFO shipments by 95% by 2010 and to ban their use after 2015, and active research has been conducted to develop alternative surfactants.

The present inventors were studying a method for producing polyvinylidene fluoride nanoparticles. In preparing polyvinylidene fluoride nanoparticles by emulsion polymerization, they used a polyethylene glycol-based compound that is a non-toxic material without using a fluorine-based surfactant. Polyvinylidene fluoride nanoparticles were prepared using the method, and found to be an economical method as well as replacement of APFO, and completed the present invention.

An object in one aspect of the present invention is to provide a method for producing polyvinyl fluoride nanoparticles using a poly(ethylene glycol)-based compound for emulsion polymerization.

An object in another aspect of the present invention is to provide polyvinyl fluoride nanoparticles manufactured using a poly(ethylene glycol)-based compound.

In order to achieve the above object, in one aspect of the present invention

Preparing a mixed solution by mixing a radical initiator, distilled water, and a compound represented by the following Chemical Formula 1 (step 1); And

Provided is a method for producing polyvinylidene fluoride (Polyvinylidene fluoride, PVDF) nanoparticles, including adding vinylidene fluoride (VDF) to the mixed solution prepared in step 1 (step 2). .

[Formula 1]

(In the formula 1,

R ₁ is hydrogen or C _1-3 alkyl,

n is 2 to 200.)

In addition, in another aspect of the present invention

Polyvinylidene fluoride (PVDF) nanoparticles, which are prepared by emulsion polymerization using the compound represented by Chemical Formula 1, are provided.

Furthermore, in another aspect of the present invention

Preparing a mixed solution by mixing a radical initiator, distilled water, and a compound represented by the following Chemical Formula 1 in a reaction vessel (step 1); And

After the reaction vessel containing the mixed solution prepared in step 1 reached a reaction temperature of 60 to 90° C. and a reaction pressure of 10 to 100 bar, the mixture was stirred at a rate of 100 to 1,000 rpm, and vinylidene fluoride. , VDF) is reacted by adding at a rate of 0.5 to 2 g/min (step 2); a method for controlling the molecular weight of polyvinylidene fluoride (PVDF) nanoparticles is provided.

Furthermore, in another aspect of the present invention

A film material including the polyvinylidene fluoride (PVDF) nanoparticles is provided.

The method for producing polyvinylidene fluoride nanoparticles according to the present invention is a process using an existing ammonium-based surfactant (ammonium perfluorinated octanoate, APFO) having 8 carbon fluoride by using a polyethylene glycol-based compound for emulsion polymerization. Not only can it be used in a much smaller amount, the compound used in the present invention has an effect that can reduce the manufacturing cost of polyvinylidene fluoride as well as APFO replacement because there is little human accumulation and toxicity.

In addition, the method for producing polyvinylidene fluoride nanoparticles according to the present invention can control the molecular weight of polyvinylidene fluoride nanoparticles prepared by controlling reaction conditions. Accordingly, the polyvinylidene fluoride nanoparticles produced by the manufacturing method according to the present invention have an effect capable of satisfying the properties required in various fields.

1 is a graph showing the monomer-polymer conversion rate showing the vinylidene fluoride injection rates in Examples 1 to 3 and Comparative Examples 1 and 2;
Figure 2 is a graph showing the monomer-polymer conversion rate showing the vinylidene fluoride injection rate in Example 4, Example 5 and Comparative Example 1;
FIG. 3 is a graph of polyvinylidene fluoride nanoparticles prepared in Example 2 analyzed by nuclear magnetic resonance spectroscopy (NMR);
4 is a graph obtained by analyzing the polyvinylidene fluoride nanoparticles prepared in Comparative Example 1 by nuclear magnetic resonance spectroscopy (NMR);
5 to 11 are photographs obtained by observing the polyvinylidene fluoride nanoparticles prepared in Examples 1 to 5 and Comparative Examples 1 and 2 with a scanning electron microscope (SEM).

In one aspect of the invention

Preparing a mixed solution by mixing a radical initiator, distilled water, and a compound represented by the following Chemical Formula 1 (step 1); And

Provided is a method for producing polyvinylidene fluoride (Polyvinylidene fluoride, PVDF) nanoparticles, including adding vinylidene fluoride (VDF) to the mixed solution prepared in step 1 (step 2). .

[Formula 1]

(In the formula 1,

R ₁ is hydrogen or C _1-3 alkyl,

n is 2 to 200.)

Hereinafter, a method of manufacturing polyvinylidene fluoride nanoparticles according to the present invention will be described in detail for each step.

First, in the method for producing polyvinylidene fluoride nanoparticles according to the present invention, step 1 is a step of preparing a mixed solution by mixing a radical initiator, distilled water and a compound represented by the following formula (1).

In step 1, the reaction materials are mixed with distilled water to prepare a polyvinylidene fluoride nanoparticle through emulsion polymerization to prepare a mixed solution. At this time, the present invention does not use a compound containing a fluorine atom or carbon fluoride, and includes a compound represented by the formula (1).

As a specific example, the compound represented by Formula 1 in step 1 is a compound such as polyethylene glycol (poly(ethylene glycol)) and polyethylene glycol methyl ether (poly(ethylene glycol) methyl ether).

The present invention does not use a compound containing a fluorine atom or carbon fluoride, which is generally used in the process of manufacturing polyvinylidene fluoride nanoparticles, and uses environmentally friendly materials such as polyethylene glycol.

In addition, the compound represented by the formula (1) in step 1 is a water-soluble substance soluble in water, and is easily removed in a purification process after a polymerization reaction.

In addition, as an example, the number average molecular weight (M _n ) of the compound represented by Formula 1 in step 1 may be 200 g/mol to 10,000 g/mol, and may be 200 g/mol to 5,000 g/mol, 200 It may be from g/mol to 1,000 g/mol, and from 200 g/mol to 900 g/mol. In addition, in Chemical Formula 1, n may be 2 to 200, 2 to 100, 2 to 50, 2 to 20, and 5 to 20.

In one example, the content of the compound represented by Formula 1 in step 1 is preferably 0.001% to 0.5% by weight, more preferably 0.003% to 0.1% by weight, and more preferably 0.003% to 0.1% by weight relative to the total mixed solution. It is preferably 0.01% by weight. If, when the content of the compound represented by the formula (1) in step 1 is less than 0.001% by weight relative to the total mixed solution, a normal emulsion droplet is not formed, so a uniform polymer cannot be obtained, and the dispersion degree of the product obtained is extremely low, so the product is actually There is a problem that can not be used, and when it exceeds 0.5% by weight, the input rate of the monomer is lowered, and it is not easy to remove the compound after the polymerization reaction, resulting in problems in the process.

In addition, as an example, the radical initiator of step 1 is sodium persulfate (Sodium persulfate), potassium persulfate (Potassium persulfate), ammonium persulfate (Ammonium persulfate), n-propyl peroxydicarbonate (n-propyl peroxydicarbonate and ammonium perfluoride As a nononate (Ammonium perfluorononanoate) can be used.

At this time, the content of the radical initiator in step 1 is preferably 0.1 to 2.0% by weight, more preferably 0.1 to 1.0% by weight relative to the total mixed solution. If, in step 1, the content of the radical initiator is less than 0.1% by weight relative to the total mixed solution, there is a problem in that the solubility of the product rapidly decreases due to an increase in molecular weight, and when it exceeds 2.0% by weight, the molecular weight falls and the mechanical However, there is a problem that leads to a decrease in thermal properties.

Next, in the method for producing polyvinylidene fluoride nanoparticles according to the present invention, step 2 is a step of adding vinylidene fluoride (Vnylidene fluoride, VDF) to the mixed solution prepared in step 1 above.

In step 2, polyvinylidene fluoride nanoparticles are prepared using the mixed solution prepared in step 1. Polyvinylidene fluoride nanoparticles having an appropriate molecular weight can be prepared by controlling the reaction temperature, reaction pressure, agitation rate, and the rate at which the monomer vinylidene fluoride is introduced.

At this time, the step 2, after reaching a reaction temperature of 60 to 90 ℃ and a reaction pressure of 10 to 100 bar, and stirred at a rate of 100 to 1,000 rpm, vinylidene fluoride (Vnylidene fluoride, VDF) 0.5 to 2 and at a rate of g/min.

As a specific example, the reaction temperature in step 2 is preferably 60 to 90 ℃. If, in step 2, the reaction temperature is less than 60 °C, there is a problem that the reaction does not occur, and when it exceeds 90 °C, it is difficult to control the molecular weight of the polyvinylidene fluoride nanoparticles produced due to the high reaction temperature. There is.

In addition, as an example, the reaction pressure in step 2 is preferably 10 to 100 bar. If, in step 2, the reaction pressure is less than 10 bar, there is a problem that the reaction rate is too low to form polyvinylidene fluoride nanoparticles, and if it exceeds 100 bar, the cost of a high-pressure device required is large. There is.

Furthermore, for example, the stirring speed in step 2 is preferably 100 to 1000 rpm. If, in step 2, the stirring speed is less than 100 rpm, there is a problem that the size of the polyvinylidene fluoride particles to be produced is non-uniform and very large, and if it exceeds 1000 rpm, the polyvinylidene fluoride nanoparticles to be produced are There is a problem that it is difficult to form a particle.

In addition, for example, in step 2, vinylidene fluoride (Vnylidene fluoride, VDF) is preferably added at a rate of 0.5 to 2 g/min. If, in step 2, when vinylidene fluoride is added at a rate of 0.5 g/min, there is a problem that the time until completion of the reaction is very slow, and when it is added at a rate exceeding 2 g/min, the reactor pressure This increases, and there is a problem that there is a risk in the process.

The molecular weight of the polyvinylidene fluoride nanoparticles can be controlled by performing emulsion polymerization under various reaction conditions as described above, and accordingly, physical properties required in various fields can be satisfied.

In addition, in another aspect of the present invention

Polyvinylidene fluoride (PVDF) nanoparticles, which are prepared by emulsion polymerization using the compound represented by Chemical Formula 1, are provided.

The polyvinylidene fluoride nanoparticles presented in the present invention are polyvinylidene fluoride nanoparticles that do not use a compound containing a fluorine atom or carbon fluoride, which is generally used, and are manufactured using environmentally friendly materials such as polyethylene glycol.

In addition, the nanoparticles can be easily produced in a much smaller amount than the conventionally used compound containing a fluorine atom or a carbon fluoride, which has the advantage of low cost.

Furthermore, in another aspect of the present invention

Preparing a mixed solution by mixing a radical initiator, distilled water, and a compound represented by the following Chemical Formula 1 in a reaction vessel (step 1); And

After the reaction vessel containing the mixed solution prepared in step 1 reached a reaction temperature of 60 to 90° C. and a reaction pressure of 10 to 100 bar, the mixture was stirred at a rate of 100 to 1,000 rpm, and vinylidene fluoride. , VDF) is reacted by adding at a rate of 0.5 to 2 g/min (step 2); a method for controlling the molecular weight of polyvinylidene fluoride (PVDF) nanoparticles is provided.

[Formula 1]

(In the formula 1,

R ₁ is hydrogen or C _1-3 alkyl,

n is 2 to 200.)

Hereinafter, a method for adjusting the molecular weight of the polyvinylidene fluoride nanoparticles according to the present invention will be described in detail for each step.

First, in the method for adjusting the molecular weight of polyvinylidene fluoride nanoparticles according to the present invention, step 1 is a step of preparing a mixed solution by mixing a radical initiator, distilled water and a compound represented by the following formula (1).

In step 1, the reaction materials are mixed with distilled water to prepare a polyvinylidene fluoride nanoparticle through emulsion polymerization to prepare a mixed solution. At this time, the present invention does not use a compound containing a fluorine atom or carbon fluoride, and includes a compound represented by the formula (1).

As a specific example, the compound represented by Chemical Formula 1 in step 1 is a compound such as polyethylene glycol (poly(ethylene glycol)) and polyethylene glycol methyl ether (poly(ethylene glycol) methyl ether).

The present invention does not use a compound containing a fluorine atom or carbon fluoride, which is generally used in the process of manufacturing polyvinylidene fluoride nanoparticles, and uses environmentally friendly materials such as polyethylene glycol.

In addition, the compound represented by the formula (1) in step 1 is a water-soluble substance soluble in water, and is easily removed in a purification process after a polymerization reaction.

In addition, as an example, the number average molecular weight (M _n ) of the compound represented by Formula 1 in step 1 may be 200 g/mol to 10,000 g/mol, and may be 200 g/mol to 5,000 g/mol, 200 It may be from g/mol to 1,000 g/mol, and from 200 g/mol to 900 g/mol. In addition, in Chemical Formula 1, n may be 2 to 200, 2 to 100, 2 to 50, 2 to 20, and 5 to 20.

In step 1, the molecular weight, particle diameter, and thermal properties of the polyvinylidene fluoride nanoparticles prepared by adjusting the number average molecular weight of the compound represented by Chemical Formula 1 can be controlled.

In one example, the content of the compound represented by Formula 1 in step 1 is preferably 0.001% to 0.5% by weight, more preferably 0.003% to 0.1% by weight, and more preferably 0.003% to 0.1% by weight relative to the total mixed solution. It is preferably 0.01% by weight. If, when the content of the compound represented by the formula (1) in step 1 is less than 0.001% by weight relative to the total mixed solution, a normal emulsion droplet is not formed, so a uniform polymer cannot be obtained, and the dispersion degree of the product obtained is extremely low, so the product is actually There is a problem that can not be used, and when it exceeds 0.5% by weight, the input rate of the monomer is lowered, and it is not easy to remove the compound after the polymerization reaction, resulting in problems in the process.

In addition, as an example, the radical initiator of step 1 is sodium persulfate (Sodium persulfate), potassium persulfate (Potassium persulfate), ammonium persulfate (Ammonium persulfate), n-propyl peroxydicarbonate (n-propyl peroxydicarbonate and ammonium perfluoride As a nononate (Ammonium perfluorononanoate) can be used.

At this time, the content of the radical initiator in step 1 is preferably 0.1 to 2.0% by weight, more preferably 0.1 to 1.0% by weight relative to the total mixed solution. If, in step 1, the content of the radical initiator is less than 0.1% by weight relative to the total mixed solution, there is a problem in that the solubility of the product rapidly decreases due to an increase in molecular weight, and when it exceeds 2.0% by weight, the molecular weight falls and the mechanical However, there is a problem that leads to a decrease in thermal properties.

Next, in the method for adjusting the molecular weight of the polyvinylidene fluoride nanoparticles according to the present invention, step 2 is a reaction temperature of 60 to 90 °C and a reaction temperature of 10 to 100 bar in the reaction vessel containing the mixed solution prepared in step 1 above. After reaching the reaction pressure, the mixture is stirred at a rate of 100 to 1,000 rpm, and then reacted by adding vinylidene fluoride (VDF) at a rate of 0.5 to 2 g/min.

In step 2, polyvinylidene fluoride nanoparticles are prepared under various reaction conditions using a reaction vessel containing the mixed solution prepared in step 1. The molecular weight of the polyvinylidene fluoride nanoparticles prepared by controlling the reaction temperature, the reaction pressure, the stirring speed and the rate at which the monomer is added may be controlled.

As described above, by adjusting the molecular weight of the polyvinylidene fluoride nanoparticles to be produced, suitable physical properties (diameter, thermal properties, etc. of nanoparticles) can be obtained according to the application to be used, and thus it can be used in various fields.

As a specific example, the reaction temperature in step 2 is preferably 60 to 90 ℃. If, in step 2, the reaction temperature is less than 60 °C, there is a problem that the reaction does not occur, and when it exceeds 90 °C, it is difficult to control the molecular weight of the polyvinylidene fluoride nanoparticles produced due to the high reaction temperature. There is.

In addition, as an example, the reaction pressure in step 2 is preferably 10 to 100 bar. If, in step 2, the reaction pressure is less than 10 bar, there is a problem that the reaction rate is too low to form polyvinylidene fluoride nanoparticles, and if it exceeds 100 bar, the cost of a high-pressure device required is large. There is.

Furthermore, for example, the stirring speed in step 2 is preferably 100 to 1000 rpm. If, in step 2, the stirring speed is less than 100 rpm, there is a problem that the size of the polyvinylidene fluoride particles to be produced is non-uniform and very large, and if it exceeds 1000 rpm, the polyvinylidene fluoride nanoparticles to be produced are There is a problem that it is difficult to form a particle.

In addition, for example, in step 2, vinylidene fluoride (Vnylidene fluoride, VDF) is preferably added at a rate of 0.5 to 2 g/min. If, in step 2, when vinylidene fluoride is added at a rate of 0.5 g/min, there is a problem that the time until completion of the reaction is very slow, and when it is added at a rate exceeding 2 g/min, the reactor pressure This increases, and there is a problem that there is a risk in the process.

The molecular weight of the polyvinylidene fluoride nanoparticles can be controlled by performing emulsion polymerization using the compound of Formula 1 under various reaction conditions as described above, and accordingly, physical properties required in various fields can be satisfied.

In addition, in one aspect of the present invention

A film material including the polyvinylidene fluoride (PVDF) nanoparticles is provided.

Polyvinylidene fluoride, a kind of fluorinated polymer, may be used in the form of a film with an electrolyte of a solar cell, or may be used in various fields such as a separator or a cathode material of a secondary battery, a water treatment membrane, and a fuel cell separator.

In particular, since a toxic surfactant is not used and the compound of Formula 1 used in the present invention is not toxic even if a small amount remains, it can be widely used in bio fields such as cell growth medium.

Accordingly, after obtaining the required properties by adjusting the molecular weight of the polyvinylidene fluoride nanoparticles according to the present invention according to the application, it can be prepared in a film form and applied to various fields.

Hereinafter, the present invention will be described in detail by the following examples and experimental examples.

However, the following examples and experimental examples are only illustrative of the present invention, and the scope of the invention is not limited by the examples and experimental examples.

< Example 1> Polyvinylidene Fluoride Preparation of nanoparticles 1

Step 1: Add 280 g of distilled water to a 1 L reaction vessel, and add 0.01 g of polyethylene glycol ((H-(O-CH ₂ -CH ₂ ) _n -OH), M _n =300) After that, the mixture was stirred at a temperature of 82° C. for 1 hour at 300 rpm.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Example 2> Polyvinylidene Fluoride Preparation of nanoparticles 2

Step 1: Add 280 g of distilled water to a 1 L reaction vessel, and add 0.01 g of polyethylene glycol ((H-(O-CH ₂ -CH ₂ )n-OH), M _n =600) After that, the mixture was stirred at a temperature of 82° C. for 1 hour at 300 rpm.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Example 3> Polyvinylidene Fluoride Preparation of nanoparticles 3

Step 1: Add 280 g of distilled water to a 1 L reaction vessel, and add 0.01 g of polyethylene glycol ((H-(O-CH ₂ -CH ₂ )n-OH), M _n =1,000) After that, the mixture was stirred at a temperature of 82° C. for 1 hour at 300 rpm.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Example 4> Polyvinylidene Fluoride Preparation of nanoparticles 4

Step 1: Add 280 g of distilled water to a 1 L reaction vessel, polyethylene glycol methyl ether, (CH ₃ -(O-CH ₂ -CH ₂ )n-OH), M _n =550 ) After adding 0.01 g, the mixture was stirred at a temperature of 82° C. for 1 hour at 300 rpm.

Thereafter, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Example 5> Polyvinylidene Fluoride Preparation of nanoparticles 5

Step 1: In a 1 L reaction vessel, 280 g of distilled water is added, and polyethylene glycol methyl ether (CH ₃ -(O-CH ₂ -CH ₂ )n-OH), M _n =750 ) After adding 0.01 g, the mixture was stirred at a temperature of 82° C. for 1 hour at 300 rpm.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring rate of.

< Comparative example 1> Polyvinylidene Fluoride Preparation of nanoparticles 1

Step 1: Add 280 g of distilled water to a 1 L reaction vessel, add 0.01 g of ammonium decafluorooctanoate (APFO) as a surfactant, and then stir at 300 rpm for 1 hour at a temperature of 82°C. Did.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Comparative example 2> Polyvinylidene Fluoride Preparation of nanoparticles 2

Step 1: After adding 280 g of distilled water to a 1 L reaction vessel, 0.7 g of Ammonium pentadecafluorooctanoate (APFO) was added as a surfactant, followed by stirring at 300° C. for 1 hour at a temperature of 82° C. Did.

Then, 0.558 g of sodium persulfate as an initiator was dissolved in 20 g of distilled water, and then added to the reaction vessel to prepare a mixed solution.

Step 2: 110 g of vinylidene fluoride (VDF) was added to the mixed solution prepared in step 1 at a rate of about 1.0 g/min, 300 rpm at a reaction temperature of 82° C. and a reaction pressure of 19.5 bar. Polyvinylidene fluoride nanoparticles were prepared by reacting at a stirring speed of.

< Experimental Example 1> Vinylidene Fluoride Analysis of polymer conversion rate of monomer

In order to confirm the reaction rate of the method for preparing polyvinylidene fluoride nanoparticles according to the present invention, in the Examples 1 to 5 and Comparative Example 1, the amount of vinylidene fluoride in the reactor was calculated and converted according to time The speed was analyzed, and the results are shown in FIGS. 1 and 2.

As shown in FIG. 1, when polyethylene glycol (poly(ethylene glycol), PEG) is used, the conversion rate is compared to that of using an ammonium-based surfactant (ammonium perfluorinated octanoate, APFO) having 8 carbon fluorides. I could confirm that it was fast. In particular, when the molecular weight is 200 to 900, preferably 300 to 600, it was confirmed that it is significantly faster.

In addition, in the case of Comparative Example 1, the conversion rate was very slow compared to the case of applying the PEG proposed in the present invention, so the amount of use was increased from 0.01 g to 0.7 g, but the conversion rate became faster, but the molecular weight and PDI were not adjusted. It was confirmed that there was a problem.

In addition, as shown in Figure 2, when using a polyethylene glycol methyl ether (poly (ethylene glycol) methyl ether, mPEG) it was confirmed that the conversion rate is fast compared to using AFPO. In particular, when the molecular weight is 300 to 600, preferably 750, it was confirmed that it is significantly faster.

< Experimental Example 2> Polyvinylidene Fluoride Analysis of physical properties of nanoparticles

In order to confirm the physical properties of the polyvinylidene fluoride nanoparticles according to the present invention, the nuclear magnetic resonance spectroscopy of the polyvinylidene fluoride nanoparticles prepared in Examples 1 to 5 and Comparative Examples 1 and 2 ¹ H-NMR, Bruker DRX-300), Scanning Electron Microscopy (SEM), Differential Scanning Calorimetry (DSC), Gel permeation chromatography (GPC), and the like were analyzed using the results. It is shown in Table 1 below.

At this time, the differential scanning calorimetry (DSC) was performed at a heating rate of 10° C./min in a temperature range of 0 to 250° C., and after heating up to the temperature of the first 250° C. to remove the heat history, it was 0 at a constant rate. After cooling to a temperature of ℃ to obtain the first cooling data, and then heated to a temperature of 250 ℃ at a constant rate to obtain the second heating data and analyzed.

3 and 4, it was confirmed that the polyvinylidene fluoride nanoparticles prepared in Examples 2 to 1 show a characteristic peak of polyvinylidene fluoride adjacent carbon.

In addition, as shown in Figures 5 to 9, it was confirmed that the polyvinylidene fluoride nanoparticles prepared in Examples 1 to 5 have a uniform size in the shape of a sphere.

Furthermore, as shown in Table 1 below, it was possible to confirm the molecular weight, particle diameter, and thermal properties as a result of preparing the polyvinylidene fluoride nanoparticles prepared in Examples 1 to 5, Comparative Examples 1 and 2, .

In particular, it was observed that Example 1 and Example 2 did not use a surfactant, and had only little difference in physical properties obtained even though only environmentally friendly polyethylene glycol was used.

Accordingly, it can be confirmed that the polyvinylidene fluoride nanoparticles produced by the manufacturing method using the eco-friendly dispersant of the present invention can satisfy physical properties required in various fields.

division
Number average molecular weight
(PDI) Particle diameter
(nm) Thermal properties Solids
content
(%) 1st cooling
Exothermic temperature (℃)/
△ H (J/g) 2nd heating
Endothermic temperature (℃)/
△ H (J/g) Example 1 387 K (2,3) 179.0 130.5 (55.5) 165.7 (57.1) 18.2 Example 2 448 K (2.6) 211.4 128.9 (54.6) 163.7 (52.1) 18.5 Example 3 414 K (2.2) 193.3 127.2 (55.3) 165.4 (53.5) 18.6 Example 4 398 K (2.3) 183.3 131.9 (53.3) 166.4 (49.4) 17.5 Example 5 448 K (2.2) 227.9 125.7 (53.5) 163.8 (51.6) 17.8 Comparative Example 1 408 K (2.5) 209.4 134.9 (56.3) 162.3 (53.3) 18.6 Comparative Example 2 240 K (3.3) 193.0 143.7 (51.8) 167.6 (56.5) 20.0

Claims (12)

Preparing a mixed solution by mixing a radical initiator, distilled water and polyethylene glycol methyl ether having a number average molecular weight (M _n ) of 750 g/mol (step 1); And
Method of producing polyvinylidene fluoride (Polyvinylidene fluoride, PVDF) nanoparticles comprising the step (step 2) of adding vinylidene fluoride (Vinylidene fluoride, VDF) to the mixed solution prepared in step 1.
delete delete According to claim 1,
The method of producing polyvinylidene fluoride nanoparticles, characterized in that the content of the compound represented by Formula 1 in step 1 is 0.001% to 0.5% by weight relative to the total mixed solution.
According to claim 1,
The radical initiator of step 1 is sodium persulfate, potassium persulfate, ammonium persulfate, n-propyl peroxydicarbonate and ammonium perfluoro nonano Method for producing polyvinylidene fluoride nanoparticles, characterized in that it is one member selected from the group consisting of eight (Ammonium perfluorononanoate).
According to claim 1,
The method for producing polyvinylidene fluoride nanoparticles, characterized in that the content of the radical initiator in step 1 is 0.1 to 1.0% by weight relative to the total mixed solution.
According to claim 1,
Step 2, after reaching a reaction temperature of 60 to 90 ℃ and a reaction pressure of 10 to 100 bar, and stirred at a rate of 100 to 1,000 rpm, vinylidene fluoride (Vnylidene fluoride, VDF) 0.5 to 2 g / Method for producing polyvinylidene fluoride nanoparticles, characterized in that it is carried out by adding at a rate of minutes.
delete Preparing a mixed solution by mixing a radical initiator, distilled water and polyethylene glycol methyl ether having a number average molecular weight (M _n ) of 750 g/mol in a reaction vessel (step 1); And
After the reaction vessel containing the mixed solution prepared in step 1 reached a reaction temperature of 60 to 90° C. and a reaction pressure of 10 to 100 bar, the mixture was stirred at a rate of 100 to 1,000 rpm, and vinylidene fluoride. , VDF) is reacted by adding at a rate of 0.5 to 2 g / min (step 2); molecular weight control method of polyvinylidene fluoride (Polyvinylidene fluoride, PVDF) nanoparticles.
delete delete delete

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