JP2006274225A - Heat-resistant fluorine-containing (meth)acrylate-based polymer and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin capable of solving problems in which PTFE requires high temperature to melt and it was difficult to apply general-purpose molding and processing, because viscosity in melting is extremely high and the applications were limited. <P>SOLUTION: The fluorine atom-containing (meth)acrylate-based polymer has a specific structure and has 10% weight reduction temperature of ≥350°C. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a fluorine atom-containing (meth) acrylic acid ester polymer having good thermal decomposition resistance, and further to a method for producing this polymer.

  In various industrial materials, an acrylic resin used as a representative of general-purpose resins has been developed for various uses, but there is a problem that its heat-decomposability is low and uses are limited. On the other hand, polytetrafluoroethylene is generally used for applications that require thermal decomposition resistance. However, polytetrafluoroethylene requires a high temperature to be melted, and furthermore, since the viscosity at the time of melting is very high, it is difficult to apply a general molding process. Moreover, when manufacturing such a resin by superposition | polymerization, there also exists a subject that a process becomes complicated.

Responding to such problems, a resin copolymerized with 2,2,3,3,3-pentafluoropropyl methacrylate, a vinyl monomer copolymerizable therewith, and a hydrophilic homopolymer has been studied. However, since it is necessary to use an expensive raw material, it was difficult to implement in terms of cost (see, for example, Patent Document 1).
JP 59-15411 A

  This invention is made | formed in view of the said subject which a prior art has, and aims at providing resin which has both heat-decomposability and favorable moldability. Moreover, it aims at providing the manufacturing method of the resin.

  As a result of intensive studies in view of the above problems, the present inventor is formed to include a repeating unit represented by the following general formulas (1) and (2), and has a 10% weight reduction temperature of 350 ° C. or higher. A fluorine atom-containing (meth) acrylic acid ester polymer is provided.

（但し、Ｒ¹およびＲ²は、それぞれ独立に、水素または炭素数１〜８のアルキル基を示し、Ｒ³は、炭素数１〜１８のアルキル基、炭素数３〜１２のシクロアルキル基、または炭素数６〜１０のアリール基を示す。）

(However, R ¹ and R ² each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, Or an aryl group having 6 to 10 carbon atoms.)

（但し、Ｒ⁴およびＲ⁵は、それぞれ独立に、水素または炭素数１〜８のアルキル基を示し、Ｒ⁶は少なくとも１個以上のフッ素原子を含有する炭素数１〜１５のフルオロアルキル基であり、ｎは０〜１０の整数を表す。）
また、一般式（２）で示される繰り返し単位の割合が、１０重量％以上であることを特徴とする前記のフッ素原子含有（メタ）アクリル酸エステル系重合体を提供した。

(However, R ⁴ and R ⁵ each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ⁶ represents a fluoroalkyl group having 1 to 15 carbon atoms containing at least one fluorine atom. And n represents an integer of 0 to 10.)
Moreover, the said fluorine atom containing (meth) acrylic acid ester type polymer characterized by the ratio of the repeating unit shown by General formula (2) being 10 weight% or more was provided.

  According to this, since it has a skeleton of a (meth) acrylic acid ester polymer and has a structure in which a fluorine atom is introduced, it is possible to achieve both high thermal decomposition resistance and good moldability. .

  In addition, the present inventors transesterify a (meth) acrylic acid ester polymer comprising a repeating unit represented by the general formula (1) with a fluorine atom-containing alcohol represented by the following general formula (3). The present invention provides a method for producing the fluorine atom-containing (meth) acrylic acid ester-based polymer, which is reacted in the presence.

（但し、Ｒ⁶は少なくとも１個以上のフッ素原子を含有する炭素数１〜１５のフルオロアルキル基またはフルオロエーテル基であり、ｎは０〜１０の整数を表す。）
また、前記一般式（３）で表されるフッ素原子含有アルコールが、下記一般式（４）であることを特徴とする前記のフッ素原子含有（メタ）アクリル酸エステル系重合体の製造方法を提供した。

(Wherein, R ⁶ is a fluoroalkyl group or a fluoroether group having 1 to 15 carbon atoms containing at least one fluorine atom, n represents an integer of 0.)
Further, the fluorine atom-containing alcohol represented by the general formula (3) is represented by the following general formula (4), and the method for producing the fluorine atom-containing (meth) acrylic acid ester polymer is provided. did.

（但し、ｍは１以上の整数であり、ｌは１以上の整数を表す。）
また、エステル交換触媒として特定のルイス酸を用いることを特徴とする前記のフッ素原子含有（メタ）アクリル酸エステル系重合体の製造方法を提供した。

(However, m is an integer of 1 or more, and l represents an integer of 1 or more.)
Moreover, the manufacturing method of the said fluorine atom containing (meth) acrylic-ester type polymer characterized by using a specific Lewis acid as a transesterification catalyst was provided.

  According to this, it becomes possible to provide a fluorine atom containing (meth) acrylic acid ester polymer suitably.

  The (meth) acrylic acid ester polymer of the present invention has both high heat decomposability and good moldability, so it can be easily shaped into various materials that require water repellency using a general molding method. Can be shaped. Moreover, according to this production method, a special polymerization facility is not required, and a fluorine atom-containing (meth) acrylic acid ester polymer can be produced easily and inexpensively.

  The present invention is a fluorine atom-containing (meth) acrylic acid formed by including repeating units represented by the following general formulas (1) and (2) and having a 10% weight loss temperature of 350 ° C. or higher. The present invention relates to an ester polymer.

（但し、Ｒ¹およびＲ²は、それぞれ独立に、水素または炭素数１〜８のアルキル基を示し、Ｒ³は、炭素数１〜１８のアルキル基、炭素数３〜１２のシクロアルキル基、または炭素数６〜１０のアリール基を示す。）

(However, R ¹ and R ² each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, Or an aryl group having 6 to 10 carbon atoms.)

（但し、Ｒ⁴およびＲ⁵は、それぞれ独立に、水素または炭素数１〜８のアルキル基を示し、Ｒ⁶は少なくとも１個以上のフッ素原子を含有する炭素数１〜１５のフルオロアルキル基であり、ｎは０〜１０の整数を表す。）
一般式（１）で表される繰り返し単位は、Ｒ¹が水素または炭素数１〜８のアルキル基であり、Ｒ²が水素または炭素数１〜８のアルキル基であり、Ｒ³が炭素数１〜１８のアルキル基、炭素数３〜１２のシクロアルキル基、または炭素数６〜１０のアリール基であれば、どのような構造であっても良い。

(However, R ⁴ and R ⁵ each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ⁶ represents a fluoroalkyl group having 1 to 15 carbon atoms containing at least one fluorine atom. And n represents an integer of 0 to 10.)
In the repeating unit represented by the general formula (1), R ¹ is hydrogen or an alkyl group having 1 to 8 carbon atoms, R ² is hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ³ is the number of carbon atoms. Any structure may be used as long as it is an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, or an aryl group having 6 to 10 carbon atoms.

  When the repeating unit represented by the general formula (1) is polymerized from a monomer unit, for example, methyl methacrylate, ethyl methacrylate, t-butyl methacrylate, methyl acrylate, ethyl acrylate, butyl acrylate or the like is used as the monomer unit. it can.

As the repeating unit represented by the general formula (2), R ⁴ is hydrogen or an alkyl group having 1 to 8 carbon atoms, R ⁵ is hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ⁶ is at least 1 As long as it is a C1-C15 fluoroalkyl group containing one or more fluorine atoms and n represents an integer of 0 to 10, any structure may be used.

  The proportion of the repeating unit represented by the general formula (2) can be arbitrarily set depending on the intended use and conditions, but is preferably 10% by weight or more. If it is less than 10% by weight, the 10% weight reduction temperature may be less than 350 ° C.

  The fluorine atom-containing (meth) acrylic acid ester polymer in the present invention can have other repeating units such as styrene and (meth) acrylic acid as long as the essence of the present invention is not impaired.

  In the present invention, the 10% weight reduction temperature is the temperature when the weight when the temperature is increased at a rate of 10 ° C./min under a nitrogen flow using a thermogravimetric measuring device is reduced by 10% with respect to room temperature. The higher the temperature, the better the thermal decomposition resistance.

  The fluorine atom-containing (meth) acrylic acid ester polymer in the present invention can be polymerized from a monomer unit. It can also be produced by reacting the coal with a fluorine atom-containing alcohol represented by the following general formula (3) in the presence of a transesterification catalyst. According to this production method, a special polymerization facility is not required, and a fluorine atom-containing (meth) acrylic acid ester polymer can be produced easily and inexpensively.

  Fluorine atom-containing alcohol represented by the following general formula 3 of the present invention

（但し、Ｒ⁶は少なくとも１個以上のフッ素原子を含有する炭素数１〜１５のフルオロアルキル基またはフルオロエーテル基であり、ｎは０〜１０の整数を表す。）
におけるＲ_fは１個以上のフッ素原子が含有される炭素数１〜１５のフルオロアルキル基又はフルオロエーテル基であれば特に制限はない。

(Wherein, R ⁶ is a fluoroalkyl group or a fluoroether group having 1 to 15 carbon atoms containing at least one fluorine atom, n represents an integer of 0.)
R _f in is not particularly limited as long as it is a fluoroalkyl group having 1 to 15 carbon atoms or a fluoroether group containing one or more fluorine atoms.

The fluoroalkyl group mentioned 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, where g is an integer of 1 or more) having a linear structure represented by (CF ₃ ) ₃ CO (CF ₂ ) _j ( j may be of a branched structure represented as follows:

  Examples of the fluorine atom-containing alcohol include 2,2,2-trifluoro-1-ethanol, 2,2,3,3,3-pentafluoro-1-propanol, and 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-decanol, 2-perfluoropropoxy- 2,2,3,3-tetrafluoropropanol, 2- (perfluorohexyl) ethanol, 2- (perfluorohexyl) propanol, 6- (perfluorohexyl) hexanol, 2- (perfluorooctyl) ethane Nord, 3- (perfluorooctyl) propanol, 6- (perfluorooctyl) hexanol, 2- (perfluorodecyl) ethanol, 1H, 1H-2,5-di (trifluoromethyl) -3,6-dioxa Undecafluorononanol, 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-hexa Decafluorononanol, 2H-hexafluoro-2-propanol, 1H, H, 3H-hexafluoro-butanol, 2,2-bis (trifluoromethyl) propanol can be exemplified.

  In the present invention, a fluorine atom-containing alcohol represented by the following general formula (4) is preferable because it provides particularly high heat decomposition resistance.

（但し、ｍは１以上の整数であり、ｌは１以上の整数を表す。）
これらの具体例としては、１Ｈ，１Ｈ，３Ｈ−テトラフルオロプロパノール、１Ｈ，１Ｈ，５Ｈ−オクタフルオロペンタノール、１Ｈ，１Ｈ，７Ｈ−ドデカフルオロヘプタノール、１Ｈ，１Ｈ，９Ｈ−ヘキサデカフルオロノナノール等を例示できる。

(However, m is an integer of 1 or more, and l represents an integer of 1 or more.)
Specific examples thereof include 1H, 1H, 3H-tetrafluoropropanol, 1H, 1H, 5H-octafluoropentanol, 1H, 1H, 7H-dodecafluoroheptanol, 1H, 1H, 9H-hexadecafluorononanol. Etc. can be illustrated.

  The transesterification catalyst in the present invention accelerates the reaction rate of the transesterification reaction.

  In the present invention, any commonly used transesterification catalyst can be used. For example, alkali metal carbonate, alkali metal bicarbonate, alkaline earth metal carbonate, alkaline earth metal bicarbonate, alkali Examples thereof include metal hydroxides, alkaline earth metal hydroxides, Lewis acids, and proton acids.

  Here, the alkali metal carbonate refers to lithium carbonate, potassium carbonate, sodium carbonate, rubidium carbonate, cesium carbonate, and francium carbonate, and potassium carbonate and cesium carbonate are particularly preferable.

  The alkaline earth metal carbonate means magnesium carbonate, calcium carbonate, strontium carbonate, or barium carbonate, and magnesium carbonate and calcium carbonate are particularly preferable.

  Alkali metal bicarbonate refers to lithium bicarbonate, potassium bicarbonate, sodium bicarbonate, rubidium bicarbonate, cesium bicarbonate, francium bicarbonate, and potassium bicarbonate is particularly preferred.

A Lewis acid is a compound that can accept an electron pair. Specifically, an electron pair such as a tin compound, a zinc compound, an ytterbium compound, a titanium compound, a vanadium compound, a zirconium compound, or a hafnium compound. Although there are acceptable metal compounds, titanium compounds, vanadium compounds, zirconium compounds, and hafnium compounds are preferred. Among these, a compound represented by titanium tetrachloride, Ti (OR _FL ) ₄ (R _FL is a C 1-15 fluoroalkyl group or fluoroalkyl ether group containing at least one fluorine atom), Vanadyl triflate (VO (SO ₃ CF ₃ ) ₂ ) is more preferable.

Protonic acid is a substance capable of releasing H ⁺ , and specifically includes hydrogen chloride, hydrogen sulfide, sulfuric acid, acetic acid, p-toluenesulfonic acid, and the like.

  Moreover, the transesterification catalyst to be used may be used singly or as a mixture of plural kinds as long as the transesterification proceeds.

  In the production method of the present invention, the (meth) acrylic acid ester-based polymer can be reacted with a fluorine atom-containing alcohol after being dissolved in a non-reactive solvent inert to the transesterification reaction.

  When the (meth) acrylic acid ester polymer is dissolved in a non-reactive solvent and then transesterified, the dissolved solution can be heated and stirred, and the structure can add a fluorine atom-containing alcohol. There is no restriction | limiting in particular, Even if it carries out in a pressure vessel, you may react using a glass container etc. under a normal pressure. In addition, the reaction progress is often promoted by removing the reaction by-product alcohol, and in some cases, it may be possible to use a device or apparatus that excludes the reaction by-product from the system. Absorbents such as molecular sieves that absorb or reactants that react only with by-products may be used and excluded from the reaction system.

  When the boiling point of the non-reactive solvent or the fluorine atom-containing alcohol to be used is very low, the transesterification reaction often requires a reaction at a high temperature.

  The non-reactive solvent is not particularly limited as long as it dissolves the (meth) acrylic acid ester polymer, but the fluorine atom-containing (meth) acrylic acid ester polymer that is a reaction product can also be dissolved. Solvents are preferred, among which fluorine atom-containing solvents such as benzotrifluoride, 2-chloro-benzotrifluoride, 4-chloro-benzotrifluoride and the like are more preferred.

  The transesterification catalyst, unreacted fluorine-containing alcohol and reaction by-product alcohol in the present invention are separated from the fluorine atom-containing (meth) acrylic acid ester polymer of the reaction product according to a conventional method, and filtered as necessary. The product is obtained as a desired product by performing a purification process such as extraction with a solvent and devolatilization.

  The present invention will be described in more detail based on examples, but the present invention is not limited to only 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 reaction rate The reaction product was divided by 3 by the integral value of OCH ₃ group of polymethyl methacrylate detected in the vicinity of 3.5 to 3.7 ppm by ¹ H-NMR (Varian Gemini-300 MHz). The integrated value of C (= O) OCH ₂ -of the ester group of the fluorine-containing (meth) acrylic acid ester polymer, which is a reaction product detected in the vicinity of (D), 4.1 to 4.4 ppm. The value divided by 2 was defined as (E), and the reaction rate was calculated as (E) / {(D) + (E)}.

(2) Measurement of fluorine content The fluorine content in the reaction product was determined by decomposing the reaction product by an oxygen flask combustion method, and then using an ion chromatograph (DX-500 manufactured by Dionex) and IonPac AG12A and AS12A (4 mmφ) as a column. × 250 mm), 0.3 mM NaHCO ₃ +2.7 mM Na ₂ CO _{3 as} an eluent, eluent flow rate 1.2 mL / min, detected with an electric conductivity detector, fluorine ion standard solution (manufactured by Kanto Chemical) ).

(3) Glass transition temperature (Tg)
Using 10 mg of the product, a differential scanning calorimeter (DSC, model DSC-50 manufactured by Shimadzu Corporation) was used to measure under a nitrogen atmosphere at a heating rate of 20 ° C./min, and determined by the midpoint method. .

(4) Using 10 mg of the contact angle measuring instrument product, using a thermogravimetric apparatus (TGA, TGA-50 type, manufactured by Shimadzu Corporation), under a nitrogen atmosphere (flow rate 50 mL / min), a rate of temperature increase of 10 The temperature was measured at 0 ° C./min, and the temperature decreased by 10% relative to the room temperature was defined as the 10% weight loss temperature.

(Production Example 1)
In a 50 mL autoclave (made by pressure-resistant glass industry) having a pressure resistance of 10 MPa, 1.0 g of commercially available polymethyl methacrylate (Sumitex LG, manufactured by Sumitomo Chemical Co., Ltd.), 2.39 g of 1H, 1H, 5H-octafluoropentanol as a non-reactive solvent After putting 10 ml of 2-chloro-benzotrifluoride and 120 mg of titanium tetrachloride as a transesterification catalyst, it was sealed. Thereafter, the autoclave was reacted in an oil bath heated to 200 ° C. for 3 hours. After allowing to cool, a solution obtained by diluting the reaction mixture 4 times with methylene chloride was added dropwise to hexane for reprecipitation, followed by filtration / drying to recover the product. The reaction rate of the obtained fluorine-containing (meth) acrylic acid ester polymer was calculated to be 34%, and the fluorine content was 31 wt%.

(Production Example 2)
The same procedure as in Production Example 1 was conducted except that 1H, 1H, 3H-tetrafluoropropanol was used as the fluorine atom-containing alcohol. The reaction rate of the obtained fluorine-containing (meth) acrylic acid ester polymer was calculated to be 34%, and the fluorine content was 19 wt%.

Example 1
Using fluorine-containing (meth) acrylic polymer obtained in Production Example 1 with a DTG-50H manufactured by Shimadzu Corporation under a nitrogen atmosphere (flow rate 50 mL / min), the heating rate is 10 ° C./min up to 500 ° C. The temperature was raised. The 10% weight loss temperature was determined from the obtained chart and found to be 363 ° C.

(Example 2)
The 10% weight reduction temperature of the fluorine-containing (meth) acrylic polymer obtained in Production Example 2 was determined by the same method as in Example 1. The temperature was 355 ° C.

(Comparative Example 1)
When the 10% weight reduction temperature of polymethyl methacrylate (Sumitex LG, manufactured by Sumitomo Chemical Co., Ltd.) was determined in the same manner as in Example 1, it was 342 ° C.

(Comparative Example 2)
When the 10% weight reduction temperature of polytetrafluoroethylene, which is a fluororesin, was determined by the same method as in Example 1, it was 500 ° C. or higher. However, although an attempt was made to produce a cast film of polytetrafluoroethylene, it was insoluble in an organic solvent, and the production of the film was difficult.

Claims (5)

Fluorine atom-containing (meth) acrylic acid ester-based polymer formed by including repeating units represented by the following general formulas (1) and (2) and having a 10% weight loss temperature of 350 ° C. or higher .

(However, R ¹ and R ² each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ³ represents an alkyl group having 1 to 18 carbon atoms, a cycloalkyl group having 3 to 12 carbon atoms, Or an aryl group having 6 to 10 carbon atoms.)

(However, R ⁴ and R ⁵ each independently represent hydrogen or an alkyl group having 1 to 8 carbon atoms, and R ⁶ represents a fluoroalkyl group having 1 to 15 carbon atoms containing at least one fluorine atom. And n represents an integer of 0 to 10.)   The fluorine atom-containing (meth) acrylic acid ester polymer according to claim 1, wherein the proportion of the repeating unit represented by the general formula (2) is 10% by weight or more. Reacting a fluorine-containing alcohol represented by the following general formula (3) with a (meth) acrylic acid ester-based polymer composed of the repeating unit represented by the general formula (1) in the presence of a transesterification catalyst. The method for producing a fluorine atom-containing (meth) acrylic acid ester polymer according to any one of claims 1 and 2.

(Wherein, R ⁶ is a fluoroalkyl group or a fluoroether group having 1 to 15 carbon atoms containing at least one fluorine atom, n represents an integer of 0.) The fluorine atom-containing (meth) acrylic acid according to any one of claims 1 to 3, wherein the fluorine atom-containing alcohol represented by the general formula (3) is the following general formula (4): A method for producing an ester polymer.

(However, m is an integer of 1 or more, and l represents an integer of 1 or more.)   The process for producing a fluorine atom-containing (meth) acrylic acid ester polymer according to claim 3, wherein a Lewis acid is used as the transesterification catalyst.