JP2007119563A - Fluorine-containing (meth)acrylic ester polymer and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluororesin which does not require specific polymerization facilities, enables its simple production, and reduces the deterioration of properties. <P>SOLUTION: The fluorine-containing (meth)acrylic ester polymer is obtained by reacting a (meth)acrylic ester polymer with a fluorine atom-containing alcohol, and the alcohol component present in the above fluorine-containing (meth)acrylic ester polymer is less than 10,000 ppm, and the fluorine-containing (meth)acrylic ester polymer can sufficiently acquires expected properties including, for example, a low refractive index, water repellency and sliding properties. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluorine-containing (meth) acrylic acid ester polymer having a reduced amount of unreacted fluorine atom-containing alcohol and by-product alcohol, and a method for producing the same.

  In recent years, various characteristics such as low refractive index, water repellency, and slidability of organic fluorine compounds have been clarified, and various fluororesins are used as industrial materials. Such a fluororesin is generally produced by polymerizing a monomer containing a fluorine atom, and in that case, a special polymerization facility is required or a polymerization time may be required for a long time. It was general (see, for example, Patent Document 1).

In addition, as a method for producing a resin having high functionality without using a special polymerization facility, a resin having a structure different from the starting material is obtained by chemically reacting an existing resin with a modifier. Various manufacturing methods have been studied (see Patent Documents 2 and 3). When a new resin is produced using such a reaction system, the expected physical properties may not be obtained due to the unreacted modifier remaining in the resin.
Japanese Patent Publication No. 58-193501 Japanese Patent Laid-Open No. 05-181095 U.S. Pat. No. 4,246,374

  The problem to be solved by the present invention is to provide a fluororesin that does not require a special polymerization facility, can be easily produced, and has little deterioration in physical properties, and specifically, an unreacted modification in the resin. Fluorine-containing (meth) acrylic acid that has a sufficient amount of expected physical properties such as low refractive index, water repellency, and slidability with a small amount of alcohol components such as fluorine-containing alcohol and / or by-product alcohol. It is to obtain an ester polymer.

  As a result of intensive studies in view of the above problems, the present inventors have invented the fluorine-containing (meth) acrylic acid ester-based polymer described below and a method for producing the same. That is, the fluorine-containing (meth) acrylic acid ester polymer of the present invention is obtained by reacting a (meth) acrylic acid ester polymer with a fluorine atom-containing alcohol represented by the following general formula (1). A fluorine-containing (meth) acrylic acid ester-based polymer, wherein the alcohol component contained in the fluorine-containing (meth) acrylic acid ester-based polymer is less than 10,000 ppm. Based polymer.

  Fluorine-containing (meth) acrylic acid ester with sufficiently low alcohol content, so that the expected physical properties such as low refractive index, water repellency and slidability can be obtained sufficiently. Based polymer.

  Such a fluorine-containing (meth) acrylic acid ester polymer of the present invention comprises a step of reacting the (meth) acrylic acid ester polymer and the fluorine atom-containing alcohol in a shear kneading apparatus, and According to the method for producing a fluorine-containing (meth) acrylic acid ester-based polymer of the present invention, the step of removing the fluorine atom-containing alcohol and the by-product alcohol by devolatilization under reduced pressure is performed in this order. It can be manufactured efficiently.

  Further, when the shear kneading device is an extruder with a vent, it becomes possible to continuously produce a fluorine-containing (meth) acrylate polymer having a sufficiently reduced residual alcohol amount, Productivity is improved.

  According to the present invention, it is possible to obtain a fluorine-containing (meth) acrylic acid ester-based polymer that can sufficiently obtain expected physical properties such as low refractive index, water repellency, and slidability.

  The present invention is a fluorine-containing (meth) acryl obtained by reacting a (meth) acrylic acid ester-based polymer that is a raw material resin with a fluorine atom-containing alcohol that is a modifier represented by the following general formula (1). An acid ester polymer, wherein the alcohol component contained in the fluorine-containing (meth) acrylic acid ester polymer is less than 10000 ppm, and relates to a fluorine-containing (meth) acrylic acid ester polymer. is there.

(However, _Rf is a C1-C15 fluoroalkyl group or fluoroalkylether group containing at least one fluorine atom, and n represents an integer of 0-10.)
The (meth) acrylic acid ester polymer used as the raw material resin of the present invention is not particularly limited. For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) ) Acrylate, t-butyl (meth) acrylate, benzyl (meth) acrylate, polymers composed of (meth) acrylic acid ester monomers such as cyclohexyl (meth) acrylate, and copolymers thereof. Among these, methyl methacrylate is preferable from the viewpoint of reactivity and cost.

  Moreover, the monomer which can be copolymerized with (meth) acrylic acid ester type monomers, such as (meth) acrylic acid, styrene, (alpha) -methylstyrene, and maleic anhydride, may be copolymerized.

  The fluorine atom-containing alcohol that can be used as the modifier of the present invention can be represented by the general formula (1).

The fluoroalkyl group R _f in the general formula (1) is not particularly limited as long as it is a fluoroalkyl group having 1 to 15 carbon atoms or a fluoroalkyl ether group containing one or more fluorine atoms.

The fluoroalkyl group referred to here is, for example, CF ₃ (CF ₂ ) _b (b is an integer of 0 to 14) or CF ₂ H (CHF) _c (CF ₂ ) _d (c and d are each an integer of 0 or more. , C + d = 0 to 14) or a branched structure such as (CF ₃ ) ₃ C.

The fluoroalkyl ether group referred to here is, for example, CF ₃ O (CF ₂ ) _e O (CF ₂ ) _f (e + f = 1 to 14, an integer of 1 or more) or CF ₂ HO (CHF ) _G O (CF ₂ ) _h (g + h = 1 to 14 and g is an integer of 1 or more), which has a linear structure represented by (CF ₃ ) ₃ CO (CF ₂ ) _j ( j may be of a branched structure represented as follows:

  Further, n representing the number of repeating units of the fluorine atom-containing alcohol represented by the general formula (1) may be an integer of 0 to 10, but the electron withdrawing property by the fluorine atom is very high and the reactivity is high. When decreasing, n is preferably 2 or more.

  Examples of such a fluorine atom-containing alcohol include 2,2,2-trifluoro-1-ethanol, 2,2,3,3,3-pentafluoro-1-propanol, 7,7,8,8,8. Pentafluoro-1-octanol, 2,2,3,3,4,4,4-heptafluoro-1-butanol, 3,3,4,4,5,5,6,6,6-nonafluoro-1 Hexanol, 4,4,5,5,6,6,7,7,7-nonafluoro-1-heptanol, 7,7,8,8,9,9,10,10,10-nonafluoro-1-decanol 2-perfluoropropoxy-2,2,3,3-tetrafluoropropanol, 2- (perfluorohexyl) ethanol, 2- (perfluorohexyl) propanol, 6- (perfluorohexyl) hexanol, 2- (Perfluorooctyl) ethanol, 3- (perfluorooctyl) propanol, 6- (perfluorooctyl) hexanol, 2- (perfluorodecyl) ethanol, 1H, 1H-2,5-di (trifluoromethyl) -3 , 6-Dioxaundecafluorononanol, 6- (perfluoro-1-methylethyl) -hexanol, 2- (perfluoro-3-methylbutyl) -ethanol, 2- (perfluoro-5-methylhexyl)- Ethanol, 2- (perfluoro-7-methyloctyl) -ethanol, 1H, 1H, 3H-tetrafluoropropanol, 1H, 1H, 5H-octafluoropentanol, 1H, 1H, 7H-dodecafluoroheptanol, 1H, 1H, 9H-hexadecafluorononanol, 2H-hexafluo 2-propanol, IH, IH, 3H-hexafluoro-butanol, 2,2-bis (trifluoromethyl) can be exemplified propanol.

  The amount of fluorine atom-containing alcohol used in the present invention can be in any range as long as the reaction proceeds, but the number of moles of ester groups (A) in the (meth) acrylic acid ester polymer that is a raw material resin When the ratio {(B) / (A)} of the number of moles (B) of the fluorine atom-containing alcohol which is a modifier for the above is usually in the range of 0.01 to 2.0, preferably 0.02 to 1. A range of 5 is more preferred. By making it within this range, the modification reaction proceeds sufficiently, and it becomes possible to sufficiently reduce the amount of unreacted residual components of the fluorine atom-containing alcohol and by-product alcohol contained in the acrylic ester polymer. In addition, raw material costs can be reduced.

  By making the total amount of the unreacted residual component of the fluorine atom-containing alcohol and the by-produced alcohol component contained in the fluorine-containing (meth) acrylic acid ester polymer less than 10,000 ppm, it contains substantially unreacted fluorine atoms. A fluorine-containing (meth) acrylic acid ester-based polymer having sufficient physical properties and sufficient heat resistance and strength as in the case where the total amount of residual alcohol components and by-product alcohol components is zero. More preferably, the total amount of the unreacted residual component of the fluorine atom-containing alcohol and the by-produced alcohol component contained in the fluorine-containing (meth) acrylic acid ester polymer is less than 1000 ppm.

  In order to make the total amount of the unreacted residual component of the fluorine atom-containing alcohol and the by-produced alcohol component contained in the fluorine-containing (meth) acrylic acid ester polymer less than 10,000 ppm, the reaction product is once used as a good solvent. It is also effective to produce a product which is dissolved in the solution and reprecipitated in a poor solvent and then dried. In addition, using a shear kneader, the (meth) acrylic acid ester polymer and the fluorine atom-containing alcohol are reacted, and the unreacted fluorine atom-containing alcohol and by-product alcohol are devolatilized under reduced pressure from the vent devolatilization port. A manufacturing method is also preferable.

  As a shear kneading apparatus used in the present invention, a (meth) acrylic acid ester polymer, a fluorine atom-containing alcohol, and, if necessary, a catalyst and an additive may be added and kneaded, and a vent devolatilization port may be provided. If there is no particular limitation, an extruder, a Banbury mixer, a roller, a mixer and the like can be mentioned. Examples of the extruder include a screw extruder such as a single screw extruder and a twin screw extruder, a hydrodynamic extruder, a ram type continuous extruder, a roll type extruder, a gear type extruder and the like. Among them, a screw extruder, particularly a twin screw extruder is preferable. There are two types of twin-screw extruders: non-mesh type co-rotating type, mesh type co-rotating type, non-mesh type counter-rotating type, and meshing type co-rotating type. Is preferable because it can rotate at high speed and can promote the mixing of the fluorine-containing alcohol with the (meth) acrylic acid ester polymer.

  In the present invention, after reacting the (meth) acrylic acid ester polymer and the fluorine atom-containing alcohol using a shear kneading apparatus, the unreacted fluorine atom-containing alcohol and by-product alcohol are separately devolatilized under reduced pressure. Even after removal, unreacted fluorine atom containing by continuously devolatilizing under reduced pressure while reacting (meth) acrylate polymer and fluorine atom-containing alcohol using a shear kneader equipped with a devolatilization port It is also possible to remove alcohol and by-product alcohol. The shear kneader is preferably an extruder equipped with one or more vent devolatilization ports with good devolatilization efficiency, and more preferably a twin screw extruder equipped with one or more vent devolatilization ports with good devolatilization efficiency. The extruders may be used alone or connected in series. The mixing order of the components is not particularly limited. In addition to the extruder, for example, a high-viscosity reactor such as a horizontal biaxial reactor such as Vivolak manufactured by Sumitomo Heavy Industries, Ltd. or a vertical biaxial agitation tank such as Super Blend is preferably used. it can.

  In the present invention, in the presence of a transesterification catalyst, a (meth) acrylic acid ester polymer and a fluorine atom-containing alcohol are used for the purpose of accelerating the transesterification reaction between the (meth) acrylic acid ester polymer and the fluorine atom-containing alcohol. You may react with.

  The transesterification catalyst accelerates the reaction rate of the transesterification reaction for converting the substituent of the ester group as in the reaction of the present invention. In the present invention, any commonly used transesterification catalyst can be used, and examples thereof include alkali metal carbonates, alkali metal bicarbonates, alkali metal hydroxides, Lewis acids, and protonic acids. .

  Here, examples of the alkali metal carbonate include lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, cesium carbonate, francium carbonate and the like, and potassium carbonate and cesium carbonate are particularly preferable.

  Examples of the alkali metal bicarbonate include lithium bicarbonate, potassium bicarbonate, sodium bicarbonate, rubidium bicarbonate, cesium bicarbonate, and francium bicarbonate, with potassium bicarbonate being particularly preferred.

  A Lewis acid is a compound that can accept an electron pair. Specifically, a tin compound, a zinc compound, an ytterbium compound, a titanium compound, a vanadium compound, a zirconium compound, a hafnium compound, and a scandium compound. , Manganese compounds, nickel compounds, samarium compounds, cadmium compounds, cobalt compounds, aluminum compounds, indium compounds, lanthanum compounds and other metal compounds that can accept an electron pair, particularly titanium compounds Vanadium compounds, zirconium compounds, hafnium compounds, and scandium compounds are preferred.

Of the metal compounds, vanadium chloride compounds, titanium chloride compounds, zirconium chloride compounds, and hafnium chloride compounds are preferred from the viewpoint of improving the reaction rate. For example, titanium tetrachloride, titanium trichloride, titanium dichlorodiisopropoxide, vanadyl chloride (VOCl ₂ ), zirconium chloride, hafnium chloride and the like can be exemplified. Among these, titanium tetrachloride is more preferable from the viewpoint of high reaction rate.

  In view of ease of handling in air, the vanadium chloride compound, titanium chloride compound, zirconium chloride compound, and hafnium chloride compound are preferably tetrahydrofuran complexes. Examples include tetrachlorobis (tetrahydrofuran) zirconium, tetrachlorobis (tetrahydrofuran) titanium, tetrachlorobis (tetrahydrofuran) hafnium, and the like.

For the same reason, it is conceivable to use an acetylacetonate complex. For example, vanadyl acetylacetonate (VO (acac) ₂ ), titanium acetylacetonate diisopropoxide, acetylacetonate hafnium, acetylacetonate zirconium and the like can be exemplified.

Further, if the titanium compound, vanadium compound, zirconium compound, and hafnium compound are alkoxides, it is preferable because no harmful hydrogen chloride is generated during the reaction. For example, titanium tetramethoxide, titanium tetraisopropoxide, titanium n-tetrabutoxide, zirconium n-butoxide, zirconium t-butoxide, zirconium n-propoxide, zirconium isopropoxide, zirconium ethoxide, hafnium tetra t-butoxide, etc. Can be illustrated. The compound is more preferably a fluorine-containing alkoxide from the viewpoint of improving the reaction rate. For example, a compound represented by Ti (OR _fc ) ₄ (R _fc is a C 1-15 fluoroalkyl group or fluoroalkyl ether group containing at least one fluorine atom) or vanadyl triflate (VO ( SO ₃ CF _{3) 2)} or the like can be exemplified.

  Among Lewis acid catalysts, those in the form of carbonates such as zirconium carbonate and scandium carbonate, scandium trifluoromethanesulfonate, ytterbium trifluoromethanesulfonate, tin trifluoromethanesulfonate, indium trifluoromethanesulfonate, trifluoromethane Those in the form of trifluoromethane sulfonates or alkyl sulfonates such as hafnium sulfonate and lanthanum trifluoromethane sulfonate can also be suitably used.

As the protonic acid, various substances capable of releasing H ⁺ can be used. Specific examples include hydrogen chloride, hydrogen sulfide, sulfuric acid, acetic acid, p-toluenesulfonic acid, and trifluoromethanesulfonic acid. The

  In the present invention, the transesterification catalyst used may be used singly or as a mixture of a plurality of types as long as the transesterification proceeds.

  The addition amount of the transesterification catalyst in the present invention can be in any range as long as the reaction proceeds, but the mole of the transesterification catalyst relative to the number of moles of ester groups (A) in the (meth) acrylic acid ester polymer. When the ratio ((C) / (A)} of the number (C) is used, a range of 0.0001 to 1.0 is usually preferable, and a range of 0.001 to 0.5 is more preferable. When the amount is less than this range, the progress of the reaction becomes difficult, and when the amount is more, a side reaction may occur.

  In the present invention, when a fluorine atom-containing alcohol is reacted with a (meth) acrylic acid ester polymer, it can be produced using a solvent inert to this reaction.

  Further, the solvent may be added to the fluorine-containing alcohol, may be added to the molten (meth) acrylic acid ester polymer, or may be added to the transesterification catalyst, and the method of adding is not particularly limited. . When the air-labile transesterification catalyst is used in the production method of the present invention, it can be suitably used as a solvent for the catalyst. Moreover, it can be suitably used as a diluent in the case of adding a viscous fluorine-containing alcohol. Solvents that are inert to the transesterification reaction include aliphatic hydrocarbons such as pentane, hexane, and cyclohexane, aromatic hydrocarbons such as benzene, toluene, xylene, chlorobenzene, and chlorotoluene, and ketones such as methyl ethyl ketone, tetrahydrofuran, and dioxane. , Fluorine compounds such as ether compounds, benzotrifluoride and 2-chloro-benzotrifluoride. These may be used singly or may be a mixture of at least two.

  The reaction temperature in the production method of the present invention is not particularly limited as long as the (meth) acrylic acid ester polymer can be melted and the transesterification proceeds, but usually it is in the range of 100 to 320 ° C. preferable. Below 100 ° C., the (meth) acrylic acid ester polymer is not sufficiently melted, and the transesterification reaction is difficult to proceed. When it exceeds 320 ° C., there is a problem that the thermal decomposition of the (meth) acrylic acid ester polymer becomes remarkable.

  As mentioned above, it is a fluorine-containing (meth) acrylic acid ester polymer obtained by reacting a (meth) acrylic acid ester polymer with a fluorine-containing alcohol, and contains fluorine atoms contained in the polymer. By setting the total amount of the unreacted residual component of alcohol and the by-produced alcohol component to less than 10,000 ppm, a material with less deterioration in mechanical and thermal properties can be provided. In addition, a fluorine-containing (meth) acrylic acid ester-based polymer can be easily produced continuously by a reaction using a shear kneader, particularly an extruder with a vent. The fluorine-containing (meth) acrylic acid ester polymer thus obtained has water repellency, oil repellency, heat resistance, weather resistance (light) resistance, chemical resistance, non-adhesiveness and releasability, low refractive index, The present invention can be advantageously used in fields where low dielectric constant, low friction coefficient, high gas permeability, low surface tension and the like are utilized.

  The present invention will be described in more detail based on examples, but the present invention is not limited only to these examples. In addition, each measuring method of the physical property measured in the following Examples and Comparative Examples is as follows.

(1) Measurement of introduction rate 10 mg of the produced reaction product was dissolved in 1 g of deuterated chloroform, and ¹ H-NMR was measured at room temperature using Varian Gemini-300 (300 MHz). From the obtained spectrum, the integrated intensity of 3.5 to 3.7 ppm attributed to the methyl ester group and the C (= O) of the methyl ester group of the raw material and the ester group of the fluorine-containing (meth) acrylic acid ester polymer. ) OCH ₂ - from the integrated intensity of 4.2~4.4ppm attributed to methylene groups, was determined introduction rate.

(2) Glass transition temperature (Tg)
Using a differential scanning calorimeter (DSC, model DSC-50 manufactured by Shimadzu Corporation), the temperature of 10 mg of the product was raised at 20 ° C./min in a nitrogen atmosphere. Used to determine the glass transition temperature (Tg).

(3) Determination of total residual amount of fluorine atom-containing alcohol and by-product alcohol component Fluorine atom-containing alcohol and methanol were dissolved in methylene chloride (made by Wako Pure Chemicals, special grade reagent), respectively, 5, 50, 500, 5000, A solution having a concentration of 50,000 PPM was prepared. 3 μl of a sample was injected into a gas chromatograph (Gas Chromatograph GC-2010AF manufactured by Shimadzu Corporation, detector FID, capillary column (Rtx-1 manufactured by Restec Co., Ltd.)) using a microsyringe. Each was measured. Measurement conditions were such that the column temperature was increased from 35 ° C. to 70 ° C. at a rate of 5 ° C./min and from 70 ° C. to 250 ° C. at a rate of 30 ° C./min. The injection temperature was 120 ° C and the detector temperature was 270 ° C. The carrier gas was helium and the flow rate was 0.5 cm ³ / sec. The split ratio was 1: 4. From the obtained chart, the peak area at each concentration of the fluorine atom-containing alcohol and methanol was read. From each concentration and peak area, a relational expression (calibration curve) between the concentration and peak area was obtained.

  Next, 0.5 g of the product was weighed into a volumetric flask having an internal volume of 10 ml and diluted with 10 ml of methylene chloride (manufactured by Wako Pure Chemicals, special grade reagent) to make a sample solution. This sample solution was measured with a gas chromatograph under the same measurement conditions as described above. The peak areas of the fluorine atom-containing alcohol and methanol were read from the obtained chart. Using the calibration curve, the fluorine atom-containing alcohol concentration and the methanol concentration (PPM) in the sample are calculated from the peak area of the fluorine atom-containing alcohol and methanol in the read sample solution. The total concentration (PPM) of the fluorine atom-containing alcohol remaining in and the alcohol component by-produced was calculated.

Example 1
Using an extruder, melted (meth) acrylic acid ester polymer (Sumitex MM manufactured by Sumitomo Chemical Co., Ltd.) was added to fluorine atom-containing alcohol 3,3,4,4,5,5,6, 6,6-Nonafluoro-1-hexanol and tin trifluoromethanesulfonate as a transesterification catalyst were added to produce a fluorine atom-containing (meth) acrylate polymer. The extruder used was a vented meshing co-rotating twin screw extruder with a bore of 15 mm. The set temperature of each temperature control zone of the extruder is 250 ° C., the screw rotation speed is 300 rpm, 100 parts by weight of (meth) acrylic ester polymer from the raw material supply port, and 5 parts by weight of tin trifluoromethanesulfonate as a transesterification catalyst. Blended in advance, the blend was charged at 0.5 kg / hr. Fluorine atom-containing alcohol was supplied to the extruder by a press-fitting pump on the downstream side from the raw material supply port of the extruder. The supply amount of the fluorine atom-containing alcohol was 65 parts by weight with respect to 100 parts by weight of the (meth) acrylic acid ester polymer. The resin was melted and filled with a kneading block and then reacted with a fluorine atom-containing alcohol. A seal ring was placed at the end of the reaction zone to fill the resin. By-products after the reaction and excess fluorine atom-containing alcohol were devolatilized by reducing the pressure at the vent port to -0.02 MPa. The resin that came out as a strand from a die provided at the exit of the extruder was cooled in a water tank and then pelletized with a pelletizer.

  The resulting fluorine atom-containing (meth) acrylic acid ester polymer has an introduction rate of 12%, a glass transition temperature of 85 ° C., and 3,3,4,4,5,5,6,6,6-nonafluoro. The total residual amount in the product of -1-hexanol and methanol was 5200 ppm.

(Example 2)
As a transesterification catalyst, 10 parts by weight of TiCl ₄ was used instead of tin trifluoromethanesulfonate, and a mixture dissolved in the same amount of hexane was supplied to the extruder by a press-in pump. The supply port was on the downstream side of the fluorine atom alcohol supply port. Except this, the same procedure as in Example 1 was performed.

  The introduction rate of the obtained fluorine atom-containing (meth) acrylic acid ester polymer was 9%, the glass transition temperature was 92 ° C., and 3,3,4,4,5,5,6,6,6-nonafluoro The total residual amount in the product of -1-hexanol and methanol was 6200 ppm.

(Example 3)
100 parts by weight of 2,2,2-trifluoro-1-ethanol was used in place of 3,3,4,4,5,5,6,6,6-nonafluoro-1-hexanol as the fluorine atom-containing alcohol Except for this, the same procedure as in Example 1 was performed.

  The introduction rate of the obtained fluorine-containing (meth) acrylic acid ester polymer was 10%, the glass transition temperature was 105 ° C., and the total in the products of 2,2,2-trifluoro-1-ethanol and methanol The remaining amount was 800 ppm.

Example 4
In a 50 mL autoclave (made by pressure-resistant glass industry) with a pressure resistance of 10 MPa, 1.0 g of (meth) acrylic acid ester polymer (Sumipex MM manufactured by Sumitomo Chemical Co., Ltd.) and 3,3,4,4 which are fluorine atom-containing alcohol , 5,5,6,6,6-nonafluoro-1-hexanol, 2.64 g of non-reactive solvent, 10 ml of 2-chloro-benzotrifluoride, and 200 mg of tin trifluoromethanesulfonate as a transesterification catalyst The reaction was carried out at a temperature of 220 ° C. and a reaction time of 3 hours. After allowing to cool, a solution obtained by diluting the reaction mixture 4 times with acetone was added dropwise to methanol for reprecipitation, followed by filtration and drying in an oven at 100 ° C. for 24 hours to recover the product.

  The introduction rate of the obtained fluorine atom-containing (meth) acrylic acid ester polymer was 52%, the glass transition temperature was 50 ° C., and 3,3,4,4,5,5,6,6,6-nonafluoro The total residual amount in the product of -1-hexanol and methanol was 5 ppm.

(Comparative Example 1)
The same procedure as in Example 1 was performed except that the vent port was decompressed and not devolatilized, and the pressure was changed to atmospheric pressure.

  The resulting fluorine atom-containing (meth) acrylic acid ester polymer had an introduction rate of 12%, a glass transition temperature of 82 ° C., and 3,3,4,4,5,5,6,6,6-nonafluoro. The total residual amount in the product of -1-hexanol and methanol was 43000 ppm, and the introduction rate was the same as in Example 1, but the glass transition temperature was lowered, and the material was inferior in heat resistance.

Claims (3)

A fluorine-containing (meth) acrylate polymer obtained by reacting a (meth) acrylate polymer with a fluorine atom-containing alcohol represented by the following general formula (1), the fluorine-containing polymer The fluorine-containing (meth) acrylic acid ester polymer characterized in that the alcohol component contained in the (meth) acrylic acid ester polymer is less than 10,000 ppm.
(However, _Rf is a C1-C15 fluoroalkyl group or fluoroalkylether group containing at least one fluorine atom, and n represents an integer of 0-10.)   In a shear kneader, the step of reacting the (meth) acrylic acid ester polymer with the fluorine atom-containing alcohol, and the unreacted fluorine atom-containing alcohol and by-product alcohol are devolatilized under reduced pressure. The process of removing is performed in this order, The manufacturing method of the fluorine-containing (meth) acrylic acid ester-type polymer of Claim 1 characterized by the above-mentioned.   The method for producing a fluorine-containing (meth) acrylate polymer according to claim 2, wherein the shear kneading apparatus is an extruder with a vent.