JPS6221805B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a fluorine-containing segmented polymer and a method for producing the same, particularly a multi-segmented polymer comprising at least two types of polymer chain segments, at least one of which is a fluorine-containing polymer chain segment, and a method for producing the same. . The fluorine-containing segmented polymer that is the object of the present invention basically consists of an iodine atom liberated from an iodide compound having an iodine atom bonded to a carbon atom, a residue obtained by removing the iodine atom from the iodide compound, and the iodine atom. It consists of at least two types of polymer chain segments (at least one of which is a fluorine-containing polymer chain segment) interposed between the atoms and the residues. In other words, the fluorine-containing segmented polymer of the present invention basically comprises at least two types of polymer chain segments (at least one of which is a fluorine-containing polymer chain segment).
It consists of such a chain, iodine atoms liberated from an iodide compound having iodine atoms bonded to carbon atoms present at both ends thereof, and residues obtained by removing the iodine atoms from the iodide compound as essential components. That is, a typical structure of the fluorine-containing segmented polymer of the present invention can be represented by _the following formula: The removed residues A, B, ... are each polymer chain segments (at least one of which is a fluorine-containing polymer chain segment), I is an iodine atom liberated from the iodide compound, n represents the number of bonds in Q. ]. Polymers having such a structure are generally called block or graft polymers. Conventionally, these have been synthesized by various methods, such as the sequential growth method used in the production of living polymers, the coupling method in which two or more types of polymers are coupled, the polyaddition or polycondensation method using terminal functional groups, Radical polymerization methods using polymer initiators or polymer transfer agents are known. While all of these methods require a prepolymer having a specific functional group at the end, various difficulties are generally involved in synthesizing such a prepolymer with high purity. On the other hand, various methods are already known for producing fluorine-containing segmented polymers having two or more types of polymer chain segments, at least one of which is a fluorine-containing polymer chain segment. . For example, a method for producing blocked telomers having low molecular weight polymer chain segments using Hg or ultraviolet rays as reaction accelerators (U.S. Pat. No. 3,900,380), A method for producing a block copolymer by polymerizing an unsaturated compound (Japanese Patent Application Laid-open No. 47-6193), a method for producing a co-telomer by reacting a bromine-containing telomer of tetrafluoroethylene with ethylene (Japanese Patent Application Laid-Open No. 1983-1999)
50-30984) and the like are known. In addition, a method of telomerizing fluoroolefins in the presence of a radical initiator using polyfluoroalkyl iodide as a telogen is also well known (for example, "telomerization" US Naval Res.Rab.Rept. .PB
131930, UK Patent No. 824229, etc.). Although the method of the present invention is carried out by a radical method, it is achieved by the method described below, which is different from the conventional telomerization method, and it also achieves the results that cannot be obtained by the conventional method described above. A new general method is provided by which molecular species of fluorine-containing multi-segmented polymers can be obtained. That is, in the method of the present invention, the carbon-iodine bond of the iodide compound is a relatively weak bond, which is easily radically cleaved by a radical generation source, and the radicals generated by the cleavage have high reactivity, so that radical polymerization is not possible. The addition-growth reaction can be caused to occur in the presence of a monomer with a specific property, and the chain reaction is then terminated by a so-called chain transfer reaction, which abstracts iodine from the iodide compound, but the resulting polymer end Since the bond between and iodine has the same reactivity as the carbon-iodine bond of the iodide compound, it is easily radicalized again by a radical generating source, and an addition growth reaction is carried out in the presence of other radically polymerizable monomers. This is based on the new knowledge that it is possible to continue the polymer chain as if it were a growing living terminal in ionic polymerization. In this way, the present invention is a new method for producing a fluorine-containing multi-segmented polymer by applying a previously unknown principle. The fluorine-containing segmented polymer provided by the present invention basically consists of a chain consisting of at least two types of polymer chain segments, an iodine atom and an iodide compound bonded to both ends of the chain, and at least one iodine atom from an iodide compound. Consists of residues excluding atoms as essential constituents. Therefore, the at least two types of polymer chain segments are different from each other (for example, the structures and compositions of the monomer units that constitute them are different) from the adjacent polymer chain segments, and their At least one of them is a fluorine-containing polymer chain segment,
and each polymer chain segment has a molecular weight
10,000 or more, but at least one of the polymer chain segments has a molecular weight of 30,000 or more, excluding the so-called telomer region. Furthermore, in the case where a polymerizable double bond exists in the iodide compound, the residue obtained by removing at least an iodine atom from the iodide compound is a monomer constituting the polymer chain segment or some substitution derived from the iodide compound. It is possible to have a certain amount of time. The fluorine-containing segmented polymer can be produced as follows. In other words, first,
At least one monomer selected from the group (A) below is radically polymerized in the presence of a radical generating source and an iodide compound to obtain a polymer chain segment having a molecular weight of 10,000 or more and composed of the monomer units, and both of them. An iodine atom free from the iodide compound bound to the terminal and a residue obtained by removing at least one iodine atom from the iodide compound (provided that the residue has a polymerizable double bond in the iodide compound). If present, it may have some substituent derived from the monomer or the iodide compound.) Produce a bresegmented polymer (first step). Next, at least one monomer selected from group (A) and group (B) described below is added to the radical generating source and the first monomer.
A chain consisting of a polymer chain segment with a molecular weight of 10,000 or more, which is radically polymerized in the presence of the pre-segmented polymer produced in the process and is composed of the polymer chain segment present in the pre-segmented polymer and the monomer unit, The iodine atoms free from the iodide compound and the residues from which at least one iodine atom has been removed from the iodide compound (provided that the residues are polymerizable to the presegmented polymer) are bonded to both ends thereof. (If a double bond is present, it may have some substituent derived from the monomer or the presegmented polymer.) A bisegmented polymer is produced (second step). If necessary, at least one monomer selected from Groups (A) and (B) described later is radically polymerized in the presence of a radical generating source and the bisegmented polymer produced in the second step. The molecular weight is composed of the polymer chain segments present in the bisegmented polymer and the monomer units.
A chain consisting of 10,000 or more polymer chain segments, and an iodine atom free from the iodide compound bonded to both ends of the chain, and a residue obtained by removing at least one iodine atom from the iodide compound (if the remaining The group may have some substituents derived from the monomer or the bisegmented polymer if polymerizable double bonds are present in the bisegmented polymer. Sesame (3rd step). If necessary, at least one monomer selected from Groups (A) and (B) described later is radically polymerized in the presence of a radical generating source and the trisegmented polymer produced in the third step. The molecular weight is composed of the polymer chain segments present in the trisegmented polymer and the monomer units.
A chain consisting of 10,000 or more polymer chain segments, and an iodine atom free from the iodide compound bonded to both ends of the chain, and a residue obtained by removing at least one iodine atom from the iodide compound (if the remaining The group may have some substituent derived from the monomer or the trisegmented polymer if a polymerizable double bond is present in the trisegmented polymer.)
(4th step). If necessary, the polymer chain segments can be successively grown by further repeating the radical polymerization in the same manner as above. In addition, in the fluorine-containing segmented polymer obtained as the final product, the molecular weight of each polymer chain segment is 10,000 or more, but at least one polymer chain segment should have a molecular weight of 30,000 or more, and the above The radical polymerization reaction in each step also needs to be carried out in such a way that such polymer chain segments are obtained. Also, although adjacent polymer chain segments are required to be dissimilar from each other, this does not mean that all polymer chain segments are dissimilar from each other. In short, it is sufficient that at least two types of polymer chain segments and at least one type of fluorine-containing polymer chain segment exist in the fluorine-containing segmented polymer. The iodide compound used in the first step described above has 1 to 16 carbon atoms (preferably 1 to 16 carbon atoms).
8) is a perhalohydrocarbon in which at least one of the halogen atoms (preferably only one on two mutually adjacent carbon atoms) is an iodine atom, and the other halogen atoms are fluorine atoms. or consisting of a fluorine atom and a chlorine atom (if chlorine atoms are present, their number is not greater than the number of fluorine atoms, and there is no more than one chlorine atom on a carbon atom) There is no chlorine atom present.) However, the iodide compound has an oxygen bond (-
O-) may also be present. It can have a substituent represented by _-CF2H or = _CF2 . The number of iodine atoms in the perhalohydrocarbon is preferably one or two, but is not necessarily limited to this. If the perhalohydrocarbon is totally unsaturated, such as when it has =CF ₂ , it is itself polymerizable and will undergo radical polymerization reactions. Therefore, an unsaturated perhalohydrocarbon, i.e., an unsaturated iodide compound, has a structure in which its (-I bond participates in the chain initiation of the radical polymerization reaction, and at the same time, the unsaturated bond participates in the chain initiation of the radical polymerization reaction. It is also useful as a monomer.Therefore, when such iodide compounds are used,
The resulting fluorine-containing segmented polymer will have a more or less complex structure. Specific examples of iodide compounds include: monoiodoperfluoromethane, monoiodoperfluoroethane, monoiodoperfluoropropane, monoiodoperfluorobutane (e.g. 2-iodoperfluorobutane, 1-iodoperfluorobutane). iodoperfluoro(1,1-dimethylethane)), monoiodoperfluoropentane (e.g. 1-iodoperfluoro(4-methylbutane)), 1-iodoperfluoro-n-nonane, monoiodoperfluorocyclobutane, 2-
Iodoperfluoro(1-cyclobutyl)ethane, monoiodoperfluorocyclohexane, 2
-Iodo-1-hydroperfluoroethane, 3
-iodo-1-hydroperfluoropropane,
Monoiodomonochlorodifluoromethane, monoiododichloromonofluoromethane, 2-iodo-
1,2-dichloro-1,1,2-trifluoroethane, 4-iodo-1,2-dichloroperfluorobutane, 6-iodo-1,2-dichloroperfluorohexane, 4-iodo-1,2- 4-Trichloroperfluorobutane, 1-iodo-2-hydroperfluoropropane, monoiodotrifluoroethylene, 3-iodoperfluoropropene-1, 4-iodoperfluoropentene-1,
4-iodo-5-chloroperfluoropentene-
1,2-iodoperfluoro(1-cyclobutenyl)ethane, 1,2-diiodoperfluoroethane, 1,3-diiodoperfluoro-n-propane, 1,4-diiodoperfluoro-n-butane, 1,3 -diiodo-2-chloroperfluoro-n-propane, 1,5-diiodo-2,4-dichloroperfluoro-n-pentane, 1,7-diiodoperfluoro-n-octane, 1-iodoperfluorodecane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, 1,2-di(iododifluoromethyl)perfluorocyclobutane, 2-iodo-
2,2-dichloro-1,1,1-trifluoroethane, 2-iodoperfluoroethyl perfluorovinyl ether, 2-iodoperfluoroethyl perfluoroisopropyl ether, and the like. In each of the above steps, monomers used to form polymer chain segments by radical polymerization include the following groups (A) and (B). That is, the (A) group includes fluorine-containing unsaturated polymerizable monomers represented by the formula: CF ₂ =CXY. Here, X represents a hydrogen atom or a fluorine atom, and when X is a hydrogen atom, Y is a hydrogen atom, and when X is a fluorine atom, Y represents a hydrogen atom, a chlorine atom, or a fluorine atom. Elementary atom, trifluoromethyl group, difluoromethyl group, perfluoroalkoxy group having 1 to 3 carbon atoms, formula: -(CF ₂ ) _n COOM
(In the formula, m is an integer of 0 to 3, M is hydrogen, sodium or potassium.) Group or formula: -(OCF ₂ ) _p -(OCF ₂ CF ₂ ) _q -(OCF ₂ CF
(CF ₃ )) _r −Z (where Z is −COF, −COOM, −
SO ₂ F or -SO ₃ M, M has the same meaning as above, p,
q and r are each integers from 0 to 3, but at least one of them is not 0. ). In addition, as group (B), carbon number 2 to
Included are unsaturated polymerizable monomers of No. 8, which do not have a fluorine atom on a carbon atom constituting a double bond. However, when the above monomers included in group (B) are used, after the radical polymerization reaction has temporarily stopped, under normal reaction conditions, further radical polymerization is performed to grow the chain of polymer chain segments. Because it is difficult to cause a reaction,
It is desirable to avoid the use of such monomers except in final steps where further chain growth is not required. In other words, for radical polymerization reactions other than the final step, it is preferable to use monomers selected from group (A) alone or together with monomers selected from group (B). In the radical polymerization reaction of each step, the number of monomers used may be one or more. When one type of monomer is used, the polymer chain segment formed is a homopolymer, and when two or more types of monomer are used, the polymer chain segment formed is a copolymer. By selecting and using appropriate monomers, the polymer chain segment formed can be made to be different from the polymer chain segments formed in the steps before and after it, for example, in steric structure and monomer composition. Bye. Specific examples of monomers belonging to group (A) include tetrafluoroethylene, trifluoroethylene, vinylidene fluoride, chlorotrifluoroethylene, hexafluoropropylene, pentafluoropropylene, perfluoro(methyl vinyl ether), perfluoro(ethyl vinyl ether). ),
Perfluoro(propyl vinyl ether), perfluoroacrylic acid, perfluorovinyl acetic acid,
Examples include perfluoro(3-vinyloxypropionic acid) and perfluoro[2-(2-fluorosulfonylethoxy)propyl vinyl ether]. Specific examples of monomers belonging to group (B) include ethylene, propylene, butene, vinyl esters (e.g. vinyl acetate), vinyl ethers (e.g. methyl vinyl ether), acrylic acid, methacrylic acid, alkyl acrylates (e.g. Methyl acrylate, ethyl acrylate,
butyl acrylate), alkyl methacrylates (eg, methyl methacrylate, ethyl methacrylate), styrene, vinyl chloride, and the like. As the radical generating source, conventionally known sources can be used as they are. Preferred radical generating sources are light and heat, which can selectively cleave I-C bonds in iodide compounds. As the light, it is possible to use a wide range of light ranging from the infrared region to the ultraviolet region. Although it is not impossible to use chemical ultraviolet light, it has the disadvantage that it sometimes generates radicals not only from I-C bonds but also from other bonds. Similar defects are observed when using ionizing radiation. When only heat is used as a radical generation source, heating to 200°C or higher is desirable. As other radical generation sources, it is also possible to use known radical initiators that do not substantially cause chain transfer reactions and exhibit an appropriate decomposition rate under radical polymerization reaction conditions. Examples of such radical initiators include inorganic or organic peroxides, azo compounds, organometallic compounds, and metals. Among these, organometallic compounds are not necessarily good because they may extract not only iodine atoms but also other atoms or atomic groups to generate radicals. Particularly recommended are persulfates, hydrogen peroxide, (R _f
CO) ₂ O ₂ , R _f OOR _f , R _f C(O)OOR _f , (R _f )
₃ COOC(O)OC(R _f ) ₃ , N ₂ F ₂ , R _f −N=N
-R _f , HgR _f2 , Li, K, Na, Mg, Zn, Hg, _Al
etc. (R _f : polyfluoroalkyl group). When using these radical initiators, it is desirable to keep their concentration as low as possible, to suppress termination due to bonding between radicals as much as possible, and to give priority to chain growth reactions. The quantitative ratio of the iodide compound and the monomer in the radical polymerization reaction may be appropriately determined so that the formed polymer chain segment has a desired molecular weight. In this case, the chain transfer constant of the iodide compound can be used as an index. For example, if the chain transfer constant of the iodide compound is relatively large, most of the iodide compound will bind to the polymer chain segment at the beginning of the radical polymerization reaction, so the reaction will proceed smoothly without special precautions. proceed. On the other hand, if the chain transfer constant is relatively small, an excess amount of iodide compound is used in the early stages of the reaction to form polymer chain segments of relatively low molecular weight, and this step allows the iodide compound to be It is desirable to remove the compound and perform further reactions to reach the desired molecular weight. Such sequential polymerization is generally effective in forming polymer chain segments with a narrow molecular weight distribution. The temperature of the radical polymerization reaction can be freely selected as long as the reaction occurs and the resulting polymer chains are not thermally decomposed, but is usually about -20 to 150°C. However, when heat is used as a radical generation source, an even higher temperature is used, and a high temperature of about 250°C may be required. Although the pressure is not limited at all, a pressure below the autogenous pressure of the monomers involved in polymerization is generally employed. However, if the chain growth reaction does not occur unless it is under extremely high pressure (for example, hexafluoropropylene or tetrafluoroethylene is polymerized with hexafluoropropylene homopolymer or hexafluoropropylene/tetrafluoroethylene copolymer with a large proportion of hexafluoropropylene). In the case of manufacturing (manufacturing) several thousand atmospheres may be required, and if the monomer is non-volatile under the reaction conditions, pressurization is virtually not required, so the range cannot be set unconditionally. The radical polymerization reaction can be carried out in any form, including bulk, solution, suspension, and emulsion. The shape may be the same throughout all steps, or a different shape may be adopted for each step.
In view of the uniformity of the reaction system, emulsion polymerization is usually most recommended. Next to emulsion polymerization,
Solution or suspension polymerization in the presence of a solvent essentially inert to radical attack may be employed. Specific examples of such solvents include perfluoro(dimethylcyclobutane), perfluorocyclohexane, dichlorotetrafluoroethane, trichlorotrifluoropropane, polyfluoroalkanes, and perfluoro(ethylene glycol methyl ethyl ether). . In the case of emulsion polymerization, it is generally desirable to use emulsifiers. However, the formed polymer chain segments are −COOM′, −OH, −
Because it has a hydrophilic group such as SO ₃ M′ (M′ is a cation such as hydrogen, sodium, or potassium), the use of an emulsifier is not necessarily necessary when it exhibits a surfactant effect. . Specific examples of emulsifiers include fluorine-containing carboxylic acids, fluorine-containing sulfonates, and the like. The emulsifier may be added to the reaction system all at once in the initial stage, or may be added in appropriate amounts continuously or intermittently. The amount of emulsifier used is preferably 5% by weight or less based on the weight of the general reaction mixture. Use of excess emulsifier should be avoided. In addition to the emulsifier, an appropriate emulsion stabilizer may be used if necessary. As mentioned above, the fluorine-containing segmented polymer is
Usually, it can be advantageously produced by emulsion polymerization, but
When the iodide compound is present in a relatively large amount in a reaction system for producing a presegmented polymer, the particles of the produced presegmented polymer easily aggregate, resulting in a significant reduction in the reaction rate. Additionally, non-segmented polymer species may be formed. Such disadvantages can be avoided by adding appropriate amounts of polymer particles corresponding to the polymer chain segments in the presegmented polymer as a seed polymer to the reaction system prior to the polymerization reaction. One feature of the fluorine-containing segmented polymer produced as described above is that it has an iodine atom at its terminal position. The terminal iodine atom can be appropriately substituted with another atom or atomic group to stabilize or activate the fluorine-containing segmented polymer. For example, hydrogen, fluorine, chlorine, bromine, hydroxy, amino, carboxyl, alkyl, thioalkyl,
By acting with a compound having an atom or atomic group such as silyl or fluorine-containing alkyl, the terminal iodine atom can be substituted with such an atom or atomic group. In addition, allyl alcohol, α-methylstyrene, diallyl phthalate,
It is also possible to add a compound having an unsaturated bond such as tetraallyl pyromellitate to the terminal. The fluorine-containing segmented polymer of the present invention exhibits various remarkable properties depending on the chain structure and composition of its polymer chain segments. In particular, a fluorine-containing segmented polymer having the following configuration collectively possesses the advantages of each polymer chain segment present in its chain, or which cannot be expected from the properties of each polymer chain segment. Due to its special properties, it has a wide range of uses in molded articles, films, sheets, filaments, etc.: A chain consisting of two or three polymer chain segments, an iodine atom present at one end of the chain, and an iodine atom present at one end of the chain; consisting of the residue of the iodide compound present at the other end of the chain with at least one iodine atom removed, one (if the chain consists of two polymer chain segments) or one or two of said polymer chain segments; (if the chain consists of 3 polymer chain segments) is (1) vinylidene fluoride/hexafluoropropylene/tetrafluoroethylene (molar ratio 45-90:5-50:0-35) polymer and (2) polymer Fluoro(alkyl vinyl ether) (alkyl has 1 to 3 carbon atoms)/tetrafluoroethylene/vinylidene fluoride (mole ratio 15-75: 0-85 (excluding 0): 0-
85) Selected from polymers, molecular weight 30000 ~
1200000 elastomeric polymer chain segments, the remainder of the polymer chain segments being (3) vinylidene fluoride/tetrafluoroethylene (molar ratio 30-100:0-70) polymer, (4) tetrafluoroethylene/hexafluoropropylene. (molar ratio
50-100:0-50) polymer and (5) tetrafluoroethylene/ethylene (molar ratio 40-60:40-
60) Selected from polymers, molecular weight 30000 ~
10,000,000 non-elastomeric polymer chain segments, with a weight ratio of elastomeric polymer chain segments to non-elastomeric polymer chain segments of 5 to 5.
40:60-95 (excluding 40:60). Polymers that generally have the properties of two or more different polymers can be obtained, for example, by blending each polymer or by random copolymerization of their respective monomers, but the fluorine-containing polymer obtained by the method of the present invention Segmented polymers can result in microblends that are not achievable with blending techniques, which can lead to completely unexpected effects, such as: That is, when rubber segments are bonded to polytetrafluoroethylene, a transparent and extremely strong soft sheet can be obtained by rolling. This can be used as a dense membrane for selectively permeable membranes, etc., and the same rubber as the above-mentioned rubbery segment is blended with this segmented polymer, and the blended rubber component is extracted from a similarly molded sheet with a solvent such as acetone. This makes it possible to obtain a semipermeable membrane or an ultrapermeable membrane having micropores. In addition, a copolymer of vinylidene fluoride and perfluoro(vinyl acetic acid) has a content of the same acid of 25 mol% or more and is a water-soluble strong polymer electrolyte. By combining them, it is possible to obtain a transparent sheet similar to that described above, and at the same time to obtain an ion exchange membrane or electrolytic diaphragm that has the properties of a strong polymer electrolyte and is moderately swellable but insoluble in water. I can do it. Furthermore, a film obtained by molding a segmented polymer obtained by bonding a segment of polytetrafluoroethylene or a copolymer segment of perfluoro(alkyl vinyl ether) and tetrafluoroethylene to poly(trifluorostyrene) using a hot roll is It has better brittleness resistance than poly(trifluorostyrene) homopolymer, and can be reacted with sulfuric anhydride to produce useful ion exchange membranes. Furthermore, the polymer having the hydrophilic group can form a so-called reversible mechanochemical system in which it rapidly contracts in the presence of an electrolyte and expands by lowering the electrolyte concentration. In addition, in particular, the fluorine-containing segmented polymer having the following structure has the brittleness of the non-elastomeric polymer chain segment improved by the elastomeric polymer chain segment, so in addition to the advantages of the non-elastomeric polymer chain segment,
Has toughness, flexibility, etc.: A chain consisting of two or three polymer chain segments and at least one iodine atom present at one end of the chain and an iodide compound present at the other end of the chain. one (if the chain consists of two polymer chain segments) or one or two (if the chain consists of three polymer chain segments) of said polymer chain segments; is (1) vinylidene fluoride/hexafluoropropylene/tetrafluoroethylene (mole ratio 45-90:5-50:0-35) polymer and (2) perfluoro(alkyl vinyl ether) (alkyl has 1 to 3 carbon atoms) )/tetrafluoroethylene/vinylidene fluoride (molar ratio 15-75: 0-85 (excluding 0): 0-
85) Selected from polymers, molecular weight 30000 ~
600,000 elastomeric polymer chain segments, the remainder of said polymer chain segments being (3) vinylidene fluoride/tetrafluoroethylene (molar ratio
30-100: 0-70) polymer, (4) tetrafluoroethylene/hexafluoropropylene (molar ratio 50
~100:0~50) polymer and (5) tetrafluoroethylene/ethylene (molar ratio 40~60:40~60)
Selected from polymers, molecular weight 100000-800000
non-elastomeric polymer chain segments, wherein the weight ratio of elastomeric polymer chain segments to non-elastomeric polymer chain segments is from 5 to
40: Something that is 60-95. In order to produce a fluorine-containing segmented polymer having the above-mentioned composite properties, monomers to constitute each polymer chain segment may be sequentially polymerized in the presence of a radical generating source and an iodide compound as described above. That is, first, at least one type of monomer is radically polymerized in the presence of a radical generating source and an iodide compound, and the molecular weight composed of the monomer units is
10,000 or more polymer chain segments, iodine atoms free from the iodide compound bonded to both ends thereof, and residues from which at least one iodine atom has been removed from the iodide compound.
When the iodide compound has a polymerizable double bond, the residue may have some substituent derived from the monomer or the iodide compound. ) to produce a pre-segmented polymer consisting of Next, at least one monomer is radically polymerized in the presence of a radical generating source and the pre-segmented polymer produced in the first step, so that the polymer chain segments present in the pre-segmented polymer and the monomer units are A chain consisting of polymer chain segments with a molecular weight of 10,000 or more, and an iodine atom released from the iodide compound bonded to both ends of the chain, and a residue obtained by removing at least one iodine atom from the iodide compound ( However, if the presegmented polymer has a polymerizable double bond, the residue may have some substituent derived from the monomer or the presegmented polymer. A bisegmented polymer is produced. Furthermore, if necessary, at least one monomer is radically polymerized in the presence of a radical generating source and the bisegmented polymer produced in the second step, so that the polymer chain segments present in the bisegmented polymer and the A chain consisting of a polymer chain segment having a molecular weight of 10,000 or more and composed of monomer units, an iodine atom released from the iodide compound bonded to both ends of the chain, and a residue obtained by removing at least one iodine atom from the iodide compound. group (if the bisegmented polymer has a polymerizable double bond, the residue may have some substituent derived from the monomer or the bisegmented polymer) A trisegmented polymer is produced. Of all the above steps, one step (if it consists of two steps) or one or two steps (if it consists of three steps) is (1) vinylidene fluoride/hexafluoropropylene/tetrafluoroethylene (molar ratio 45 to 90:5). ~50:0~35) polymer and (2) perfluoro(alkyl vinyl ether) (alkyl has 1 to 3 carbon atoms)/tetrafluoroethylene/vinylidene fluoride (molar ratio 15~75:0
~85 (excluding 0): Forms an elastomeric polymer chain segment with a molecular weight of 30,000 to 1,200,000 selected from polymers (0 to 85), and the remaining steps are (3) vinylidene fluoride/
Tetrafluoroethylene (mole ratio 30-100:0-
70) Polymer, (4) Tetrafluoroethylene/hexafluoropropylene (molar ratio 50-100:0-
50) Polymer and (5) Tetrafluoroethylene/
forming non-elastomeric polymer chain segments with a molecular weight of 30,000 to 1,000,000 selected from ethylene (40-60:40-60 molar ratio) polymers, wherein such elastomeric polymer segments and non-elastomeric polymer chains The type and composition of monomers and the conditions of the radical polymerization reaction are appropriately selected so that the segments are formed at a weight ratio of 5 to 40:60 to 95 (excluding 40:60). In addition, when the purpose is to produce a fluorine-containing segmented polymer with particularly improved brittleness, one step (in the case of two steps) or one or two steps (in the case of three steps) of all the above steps. )teeth
(1) Vinylidene fluoride/hexafluoropropylene/tetrafluoroethylene (molar ratio 45~
90:5-50:0-35) polymer and (2) perfluoro(alkyl vinyl ether) (alkyl has 1-3 carbon atoms)/tetrafluoroethylene/vinylidene fluoride (molar ratio 15-75:0-85 ( However, the remaining steps are (3) vinylidene fluoride/tetrafluoroethylene (mol (30-100:0-70) polymer, (4) tetrafluoroethylene/hexafluoropropylene (molar ratio 50-100:0-50) polymer, and (5) tetrafluoroethylene/ethylene (molar ratio 40-60:40) ~60) forming a non-elastomeric polymer chain segment having a molecular weight of 100,000 to 800,000 selected from polymers,
The type and composition of monomers and the conditions of the radical polymerization reaction are selected so that such elastomeric polymer chain segments and non-elastomeric polymer chain segments are formed in a weight ratio of 5 to 40:60 to 95. Just do it as appropriate. The present invention will be explained in more detail with reference to Examples below. In addition, the abbreviations in the examples have the following meanings: VdF, vinylidene fluoride; HFP, hexafluoropropylene; APS, ammonium persulfate; TFE, tetrafluoroethylene;
PTFE, polytetrafluoroethylene; PVdF,
Polyvinylidene fluoride; 6FI, perfluoroisopropyl iodide. Example 1 200 ml of the VdF/HFP presegmented polymer dispersion obtained in Reference Example 1 and 800 ml of pure water were placed in a pressure-resistant reaction tank with an internal volume of 3000 ml, and the internal space was sufficiently replaced with nitrogen gas. 95℃ under pressure
Heat treated for 40 min at 70 min followed by removal of nitrogen gas.
It was pressurized to the indicated pressure with the indicated monomer-based gas at °C. Subsequently, 6 ml of a 0.5% aqueous solution of APS was injected under stirring, and polymerization started immediately. Polymerization was continued while maintaining the indicated pressure range by pressurizing the mixed gas. The time (minutes) for the polymerization pressure to drop from the highest pressure to the lowest pressure is divided by the pressure difference and is shown in the table as minutes/cycle. When the proportion of each monomer-based polymer in the produced polymer reached the indicated value, the temperature was lowered and the pressure of the monomers was completely released to stop the polymerization. The contents are a white aqueous dispersion, which is coagulated by freezing, washed with water, and dried. The resulting bisegmented polymer was extracted using a Soxhlet extraction apparatus using acetone as a solvent for 18 hours, and separated into acetone-soluble and insoluble polymers. The following table shows the proportion of undissolved matter (% by weight) and also shows the iodine content of both.

【table】

[Table] TFE segmented polymer is transparent and has rubber-like properties, but when pressed with a roll at room temperature to 200℃, the elongation rate is less than 100% and the tensile strength is more than 500Kg/ ^cm2. Furthermore, it can be made into a thin film. Such properties are not limited only to the composition of this example, but also to a few percent of the TFE segment.
It is allowed to contain up to 90% or more, and the more TFE segments there are, the higher the temperature required for the pressing operation. In addition, the properties of the TFE segment are that the melting temperature of the TFE segment is 320°C or higher in differential thermal analysis (heating rate of 10°C/min), and the intrinsic viscosity [η] (35°C, dl /g, methyl ethyl ketone) of 0.2 or more exhibited sufficient performance, and the higher the molecular weight of both segments, the greater the strength and the tendency to become more tenacious. Further, this property is particularly excellent when polyiodide or unsaturated iodide is used as the iodide for preparing the presegmented polymer. In addition, when preparing the above-mentioned sheet, even if a terminally reacted presegmented polymer is mixed in, or another rubber may be further blended, the roll operation will be easier. Furthermore, there is no particular problem in mixing a small amount of PTFE-only molecules. The sheet thus obtained has no residual stress;
It did not shrink even when heated above 327℃, and differential thermal analysis showed that when the content of polymer chain segments in TFE was small, that is, when its molecular weight was relatively small, the temperature at 327℃ In addition, there may be a double peak type with a melting peak at even lower temperatures, but for those with a molecular weight of at least tens of thousands or more, the melting point is 327°C, which is recognized as the equilibrium melting point of PTFE. In addition, according to the X-ray diffraction of the sheet thus obtained, there are cases in which a relatively wide diffraction peak with a maximum value at a diffraction angle of 2θ = 17.7° is observed;
It is different from the sharp diffraction peak at °. Furthermore, according to the infrared absorption spectrum of the sample made into a thin film with a heating roll, it is 2850 cm ^-1 and 2920 cm ^-1
In some cases, absorption that is not present in segmented polymers may appear, but this is probably due to recrystallization of radicals generated by molecular scission.

This is thought to be due to the formation of the structure: [Formula] (X and Y are fluorine-containing alkyl groups). These properties can be obtained by the so-called dispersion blending method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated, or by the same dispersion blending method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated, or by the same dispersion blend method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated, or by the same dispersion blend method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated, or by the same dispersion blend method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated, or by the same dispersion blend method, in which aqueous dispersions of the same HFP/VdF rubber and PTFE are mixed and then coagulated.
It was virtually impossible to obtain this by polymerizing TFE in the presence of HFP/VdF rubber. The sheets and thin films obtained as described above are useful materials for gaskets, various membranes, packaging materials, building materials, etc. A sheet formed by compression molding a segmented polymer with VdF at 200°C is much softer than PVdF. This polymer could be dissolved in hot acetone to form a homogeneous solution. Even when this was cooled to room temperature, it remained a solution, and a transparent film was obtained by coating it on a glass plate and drying it. According to the infrared absorption spectrum of this film, it was found that the polymer chain segment of VdF was crystallized and assumed the β type, which was also confirmed by X-ray diffraction at a diffraction angle of 2θ.
It can be seen that this is an almost pure β-type crystal with a peak only at =18°. Mix 10g of titanium oxide for paint with 100ml of this acetone solution (10% by weight), shake well with hard glass beads in a high-vibration shaker to evenly disperse the composition, and apply the resulting composition uniformly onto the steel plate with a brush. death,
A white coating film was obtained by air drying. This coating film adhered relatively firmly to the steel plate, and no change in performance was observed even after it was left outdoors for about 10 months. It is useful as a paint resin and a plastic with good adhesive properties. 20 in segmented polymers with TFE/HFP system
The polymer combined with ~30% by weight of VdF/HFP rubber component was hot plate molded at 340°C to easily obtain a film. Although the molecular weight is less than 100,000, it is extremely strong and has almost no change in hardness, whereas a TFE/HFP copolymer with the same molecular weight and the same TFE/HFP composition will break due to bending. Note that this film could be easily bonded to the VdF/HFP rubber sheet using a hot plate press. However, the heat resistance limit of the segmented polymer of this example is 350° C., and at temperatures higher than this, thermal decomposition of the segments occurs, and when heated for a long time, the polymer as a whole becomes colored and deteriorates. It has been found in other examples that when a HFP content of 40 mol% or more is used, deterioration occurs but coloring property disappears. In addition, temperature-rising differential thermal analysis (10
The melting of the TFE/HFP-based segment occurred between 290 and 310°C according to the temperature increase rate (°C/min). Example 2 Reference example 2 was placed in a glass pressure-resistant reaction tank with an internal volume of 1000 ml.
Pour 300 ml of the PTFE dispersion obtained in step 1, and after sufficiently replacing the internal space with VdF/HFP (molar ratio 45:55) mixed gas, pressurize the mixed gas.
The temperature was maintained at 30° C. and 12 Kg/cm ² G, and ultraviolet rays were irradiated from a distance of 10 cm from the bottom using a 400 W high-pressure mercury lamp to carry out polymerization. Polymerization began to occur gradually over an induction period of about 1 hour, with a pressure drop of 0.5 Kg/cm ² G after 6 hours. The resulting dispersion was coagulated by freezing, washed with water, and dried to yield a slightly sticky PTFE-like polymer. This was subjected to Soxhlet extraction with acetone for 18 hours, and then an infrared absorption spectrum analysis of the unextracted polymer was performed.
The bonding of the PTFE segments was confirmed. Even if the same thing is done with a PTFE dispersion that does not contain iodine, no bonding between the rubber and PTFE is observed. Example 3 (1) Put 400 ml of the dispersion obtained in Reference Example 3 and 600 ml of pure water into a 3000 ml internal volume pressure-resistant reaction tank, and after sufficiently replacing the internal space with VdF/HFP (78/22 molar ratio) mixed gas. , 14Kg/cm ² G for the same gas at 80℃
10 ml of a 0.4% by weight aqueous solution of APS was injected. A pressure drop began immediately, but the polymerization virtually stopped after 2.5 hours when a pressure drop of about 2 kg/cm ² G occurred. (2) In exactly the same manner as (1), after 2.5 hours the same concentration as above.
When 5 ml of APS aqueous solution is additionally pressurized, polymerization starts again at the same speed as in (1). Then, after 1.8 hours, the polymerization actually stopped again, so APS was added under pressure again to carry out the reaction, and after a total of 7 hours, the temperature was rapidly lowered and the pressure was released to stop the polymerization. After freezing and coagulating from the dispersion produced in (1) and (2), the powdered polymer is obtained by washing with water and drying.
When these were dissolved in hot acetone, they formed a homogeneous solution even at room temperature, making it possible to create a transparent and tough film on a glass plate. Also, a hot plate can be used to mold transparent sheets of any thickness. According to the infrared absorption spectrum of the film produced by solution casting described above, the degree of crystallinity is low, but it is found that it is rich in the previously known β-type crystal structure.
This can be seen from the presence of significant absorption at 980, 800, 770, 617, and 536 ^{cm -1} . In addition, X-ray diffraction of the sheet obtained by compression molding at 200°C and rapid cooling shows that it is different from ordinary PVdF as shown in Figure 1, and as shown in case (2), solution casting showed a different pattern with the film. These results are considered to be due to the influence of the segment ratio and molding conditions on the crystallinity and microphase-separated structure. The polymer of this example (particularly produced by solution casting using acetone) is unique in that it contains a large amount of β-type crystals, and is useful for obtaining a film element with excellent dielectric constant and piezoelectric coefficient. Moreover, the elongation specific tension curve (25°C) of the hot plate molded sheet is shown in FIG. As is clear from FIG. 2, the introduction of the HFP/VdF rubber segment softens the PVdF slightly, but increases the elongation and improves the so-called brittleness. Example 4 (1) Add 3000 parts of pure water to a pressure-resistant reaction tank that can hold 6000 parts of water.
part and ammonium perfluorooctanoate 3
After the internal space was completely replaced with pure nitrogen gas, the pressure was increased to 15 Kg/cm ² G with stirring at 80° C. using a mixed gas of VdF/HFP/TFE (20/69/11 molar ratio). When 4 parts of 1% APS aqueous solution is pressurized into the tank,
The pressure will drop immediately, so make sure to maintain the pressure.
The reaction was continued while a mixed gas of VdF/HFP/TFE (50/30/20 molar ratio) was injected under pressure, and when the reaction amount reached 2 parts, 3.1 parts of 1,4-diiodoperfluorobutane was injected under pressure. After that, APS 1 every 3 hours.
After carrying out the reaction for 15 hours while pressurizing 2 parts of % aqueous solution, the reaction was terminated by rapidly lowering the temperature and releasing gas. A white aqueous dispersion with a solids content of 25% was obtained. This dispersion is
It was possible to coagulate using a line mixer with strong shearing force, and the coagulated product was washed with water and dried to obtain a colorless and transparent elastic polymer. Iodine content 0.18%.
[η] 0.45 (dl/g, 35°C, MEK). (2) 350ml of dispersion obtained in (1), pure water
1150ml, ammonium perfluorooctanoate
Put 1.15g into a 3000ml reaction tank and empty the internal space.
After sufficient replacement with TFE, pressurize to 15Kg/cm ² G with stirring at 80℃ with TFE/ethylene (90/10 molar ratio) mixed gas.
10 ml of a 0.1% aqueous solution of APS was injected under pressure to initiate polymerization. The reaction was continued by injecting a mixed gas of TFE/ethylene (52/48 molar ratio) to compensate for the pressure drop and adding 5 ml of 0.1% aqueous solution of APS every 3 hours. After 13.5 hours, 400 g of When the mixed gas was consumed, the reaction was stopped by depressurizing and cooling. The reaction product was a powdered polymer dispersed in slightly cloudy water. The granular powder obtained by thoroughly washing the polymer with water in a mixer and drying it was able to be compression molded on a hot plate at 290°C to form a strong sheet. In comparison with TFE/ethylene-based copolymers that do not contain soft segments, the bending annealing test at 180°C (JIS No. 3 dumbbell specimen bent and fixed at 180°
It has the characteristic that it will not be destroyed even if it becomes white when annealed at 180℃ for 24 hours. Example 5 In a stirred reaction tank with an internal volume of 400 ml, 200 ml of pure water, 1 g of ammonium perfluorooctanoate, and
After adding 10mg of APS and thoroughly replacing the internal space with TFE, 1,4-diiodoperfluorobutane was added.
0.1g and VdF/TFE/perfluoro(methyl vinyl ether) (PMVE) (60/20/20 molar ratio)
Immediately after injecting 27.5 g of the mixture, under stirring,
The temperature was raised to 60°C. The pressure rises to a maximum of 34Kg/cm ² G, but gradually decreases to 4Kg/cm ² after 2.5 hours.
It dropped to G. Here again the above monomer mixture
After 27.5 g was injected, the reaction continued. After 2 hours, the pressure decreased again to 4 kg/cm ² G, so the pressure was released, the temperature was lowered, and the contents were taken out to obtain a white aqueous dispersion. A portion of the dispersion was broken with a 2% aqueous magnesium chloride solution, washed with water, and dried to obtain a rubbery copolymer. The solid content concentration of the dispersion was 20.5%. 100 ml of this dispersion was diluted twice, the internal space was sufficiently replaced with VdF in the same reaction tank, and when the pressure was increased to 15 Kg/cm ² G with VdF while stirring at 70°C, the pressure began to decrease. The reaction was continued for 7 hours while injecting 10 ml of APS 0.01% aqueous solution every 3 hours, and when 35 g of VdF was consumed, the reaction was stopped by releasing the pressure and cooling. The properties of the polymer obtained by processing the product in a mixer and drying were almost the same as in Example 3. Example 6 (1) Put 1.5 g of pure water and 30 g of ammonium perfluorooctanoate into a pressure-resistant reaction tank with an internal volume of 3,
After sufficiently replacing the internal space with nitrogen gas, add 300g of perfluoro(propyl vinyl ether) (PPVE).
Press into the TFE and set the temperature to 50℃ while stirring.
The pressure was adjusted to 3.5 Kg/cm ² G. here,
When 20ml of 1% aqueous solution of APS is injected, the pressure starts to drop, so when the pressure drops to 3Kg/cm ² G, 1.
1.6 g of 4-diiodoperfluorobutane was press-fitted. The reaction rate decreased slightly once, but when TFE was continuously injected and the reaction was continued at 3.0 to 3.5 Kg/cm ² G, the reaction rate gradually recovered. After continuing the reaction for 14 hours, the internal pressure was released and the temperature was lowered to room temperature.
The polymerization reaction was stopped. The product was a white aqueous dispersion with a small amount of vinyl ether remaining in liquid form. The solids content of an aqueous dispersion is
It was 20.7%. After removing volatile components under a reduced pressure of 200 mmHg at 60°C, a portion was added to a large amount of acetone and treated with a mixer to destroy the dispersion, washed with water, and dried to obtain a rubbery crumb. . The PPVE content by high temperature NMR analysis is
38 mol%, number average molecular weight by GPC (solvent: trichlorotrifluoroethane) is 1.1×10 ⁵ , DSC
The glass transition temperature was 2°C. Further, the iodine content according to chemical analysis was 0.22%. (2) 350ml of dispersion obtained in (1), pure water
Put 1150ml into the same reaction tank, replace the internal space with TFE, inject 60g of PPVE, and heat at 80℃ with stirring.
Pressure was applied to 8 Kg/cm ² G using TFE. As the pressure started to decrease, the pressure was compensated with TFE and the reaction was continued under constant pressure. After 2 hours, add APS 0.1% aqueous solution 10
After the reaction was continued for 7 hours, the pressure was released and the mixture was cooled to obtain an aqueous polymer dispersion. This was vigorously stirred in a mixer to form a powdered polymer, washed with water, and dried to yield 230 g. This polymer is rated at 260℃ according to DSC.
It showed a melting temperature of , and could be made into a transparent sheet by hot plate molding at 300℃. Reference example 1 15 kg of demineralized pure water and ammonium perfluorooctanoate are placed in a pressure-resistant reaction tank that can hold 35 kg of water.
After 0.075Kg was added and the internal space was sufficiently replaced with HFP while stirring, a HFP/VdF mixed gas with a molar ratio of 55/45 was introduced and the pressure was increased to 12Kg/cm ² G at 80℃, and 0.024Kg of 6FI was injected at the same time. do. After that, APS0.01
Dissolve Kg in 0.05Kg of pure water and inject it under pressure. The polymerization reaction starts immediately and a drop in pressure occurs, so the molar ratio
Pressurize and replenish the 21/79 HFP/VdF mixed gas and continue the reaction while maintaining the pressure. 6FI is mostly consumed in the very early stage of the reaction (about 10% of the total reaction). After 5 hours, the pressure was released to terminate the reaction. The contents are a white aqueous dispersion with a polymer concentration of 13% by weight. After freezing and coagulating this, the product obtained by washing with water has an HFP content of 20 mol% and an iodine content of 0.38% by weight. In the infrared absorption spectrum of this material, absorption at 920 cm ^-1 cannot be detected due to the influence of other absorptions. The presegmented polymer obtained as described above is used for preparing the fluorine-containing segmented polymer of the present invention. Reference example 2 Water in a stainless steel autoclave with an internal volume of 3000ml
1000ml, ammonium perfluorooctanoate
Add 2.3g of n-paraffin wax and 50g of n-paraffin wax, replace the internal space with TFE, and heat at 80℃ for 50 minutes.
Pressurize to Kg/cm ² G. Next, press-fit 1ml of 6FI,
After 30 minutes with moderate stirring, 20 ml of an aqueous solution containing 1 g of APS/100 ml was injected under pressure to initiate polymerization. The pressure immediately started to drop, so TFE was added quantitatively and the reaction was continued for 2 hours while maintaining the pressure.
Obtain PTFE dispersion. Reference example 3 Pure water 1500ml in a pressure-resistant reaction tank with an internal volume of 3000ml
ml, add 30g of ammonium perfluorooctanoate, replace the internal space with VdF, and then add 0.5ml of 6FI.
(25℃) followed by 21Kg/cm ² G at 80℃
Pressure was applied to the tube, and 10 ml of an APS 0.4% by weight aqueous solution was then pressurized. Since the pressure immediately started to drop, the pressure was continued for 4 hours by injecting VdF, and then the polymerization was stopped by rapidly cooling and releasing the pressure. The product was a white translucent aqueous dispersion with a polymer concentration of 12.3% by weight. In addition, the intrinsic viscosity [η] = 0.84 was measured for the polymer powder obtained by coagulation, washing, and drying.
(dl/g, 35°C, dimethylacetamide) was obtained.

[Brief explanation of the drawing]

Figure 1 is an X-ray diffraction graph, and (a) is a normal
PVdF, (b) shows the pattern of the polymer of Example 3(1), and (c) shows the pattern of the polymer of Example 3(2) (the broken line is the solution casting film). FIG. 2 is a graph showing the elongation specific tension curve (25° C.) of the hot plate molded sheet according to the present invention, and the numbers on the shoulders indicate the weight percent of the rubber segments relative to the whole. Note that the arrow indicates that the fracture occurred there.

Claims (1)

[Claims] 1. A chain consisting of two or three polymer chain segments, an iodine atom present at one end of the chain, and at least one iodine atom from an iodide compound present at the other end of the chain. one (if the chain consists of two polymer chain segments) or one or two (if the chain consists of three polymer chain segments) of said polymer chain segments (1) Vinylidene fluoride/hexafluoropropylene/tetrafluoroethylene (molar ratio 45-90:5-50:0-35) polymer and (2) perfluoro(alkyl vinyl ether) (alkyl has 1 to 3 carbon atoms)/tetrafluoro Ethylene/vinylidene fluoride (molar ratio 15-75: 0-85 (excluding 0): 0-
85) Selected from polymers, molecular weight 30000 ~
1200000 elastomeric polymer chain segments, the remainder of the polymer chain segments being (3) vinylidene fluoride/tetrafluoroethylene (molar ratio 30-100:0-70) polymer, (4) tetrafluoroethylene/hexafluoropropylene. (molar ratio
50-100:0-50) polymer and (5) tetrafluoroethylene/ethylene (molar ratio 40-60:40-
60) Selected from polymers, molecular weight 30000~
10,000,000 non-elastomeric polymer chain segments, with a weight ratio of elastomeric polymer chain segments to non-elastomeric polymer chain segments of 5 to 5.
A fluorine-containing segmented polymer having a ratio of 40:60 to 95 (excluding 40:60).