U.S. patent application number 11/079276 was filed with the patent office on 2005-08-18 for fluorinated diene compound and fluoropolymer, and methods for their production.
This patent application is currently assigned to ASAHI GLASS COMPANY LIMITED. Invention is credited to Kashiwagi, Kimiaki, Murotani, Eisuke, Ogawa, Gen, Oharu, Kazuya, Okazoe, Takashi, Watanabe, Kunio.
Application Number | 20050182217 11/079276 |
Document ID | / |
Family ID | 19149496 |
Filed Date | 2005-08-18 |
United States Patent
Application |
20050182217 |
Kind Code |
A1 |
Kashiwagi, Kimiaki ; et
al. |
August 18, 2005 |
Fluorinated diene compound and fluoropolymer, and methods for their
production
Abstract
A novel fluoropolymer which can be an optical resin material
having a low refractive index and excellent heat resistance, and a
novel fluorinated diene compound having two unsaturated bonds,
capable of presenting such a fluoropolymer, are presented. Further,
by virtue of the low refractive index and excellent heat
resistance, the polymer presents a high performance optical
transmitter and a plastic optical fiber. A fluorinated diene
compound represented by CF.sub.2.dbd.CFCF(OR.sup.f)CF.-
sub.2OCF.dbd.CF.sub.2 (wherein R.sup.f is a perfluoroalkyl group
such as a trifluoromethyl group), and a fluoropolymer thereof.
Further, an optical transmitter made by using such a fluoropolymer,
and a plastic optical fiber having a core comprising such a
fluoropolymer and a fluorinated low molecular compound contained
therein as a refractive index-increasing agent.
Inventors: |
Kashiwagi, Kimiaki;
(Kanagawa, JP) ; Ogawa, Gen; (Kanagawa, JP)
; Okazoe, Takashi; (Kanagawa, JP) ; Watanabe,
Kunio; (Kanagawa, JP) ; Murotani, Eisuke;
(Kanagawa, JP) ; Oharu, Kazuya; (Kanagawa,
JP) |
Correspondence
Address: |
OBLON, SPIVAK, MCCLELLAND, MAIER & NEUSTADT, P.C.
1940 DUKE STREET
ALEXANDRIA
VA
22314
US
|
Assignee: |
ASAHI GLASS COMPANY LIMITED
Tokyo
JP
100-8405
|
Family ID: |
19149496 |
Appl. No.: |
11/079276 |
Filed: |
March 15, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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11079276 |
Mar 15, 2005 |
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10834076 |
Apr 29, 2004 |
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6911513 |
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10834076 |
Apr 29, 2004 |
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PCT/JP02/11311 |
Oct 30, 2002 |
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Current U.S.
Class: |
526/252 ;
526/247; 526/253; 568/683 |
Current CPC
Class: |
G02B 1/046 20130101;
C07C 43/17 20130101; G02B 1/046 20130101; G02B 6/02033 20130101;
C08F 16/32 20130101; G02B 6/02038 20130101; C08F 214/18 20130101;
C08L 29/10 20130101 |
Class at
Publication: |
526/252 ;
526/253; 526/247; 568/683 |
International
Class: |
C08F 136/16 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 31, 2001 |
JP |
2001-334352 |
Claims
What is claimed is:
1. A fluorinated diene compound represented by the following
formula (1):CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2
(1)wherein R.sup.f is a perfluoroalkyl group.
2. The fluorinated diene compound according to claim 1, wherein
R.sup.f is a trifluoromethyl group.
3. A method for producing a fluorinated diene compound represented
by the following formula (1), characterized in that a
dehalogenation reaction is carried out at halogen atoms other than
fluorine atoms in at least one compound selected from a compound
represented by the following formula (2) and a compound represented
by the following formula
(3):CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2
(1)CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2
(2)CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCFZ.sup.3CF.sub.2Z.sup.4
(3)wherein R.sup.f is a perfluoroalkyl group, and each of Z.sup.1,
Z.sup.2, Z.sup.3 and Z.sup.4 which are independent of one another,
is a halogen atom other than a fluorine atom.
4. A fluoropolymer comprising monomer units formed by
cyclopolymerization of a fluorinated diene compound represented by
the formula (1), or monomer units formed by cyclopolymerization of
a fluorinated diene compound represented by the formula (1) and
monomer units formed by polymerization of other monomer
polymerizable with the fluorinated diene compound represented by
the formula (1):CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub-
.2OCF.dbd.CF.sub.2 (1)wherein R.sup.f is a perfluoroalkyl
group.
5. The fluoropolymer according to claim 4, wherein R.sup.f is a
trifluoromethyl group.
6. The fluoropolymer according to claim 4, wherein the monomer
units formed by the cyclopolymerization of the fluorinated diene
monomer represented by the formula (1), are monomer units
represented by any one of the following formulae, wherein R.sup.f
is as defined above: 6
7. The fluoropolymer according to claim 4, wherein the monomer
units of other polymerizable monomer are monomer units formed by
polymerization of at least one member selected from a fluorinated
diene which is cyclopolymerizable, other than the fluorinated diene
compound represented by the formula (1), a monomer having a
fluorinated aliphatic cyclic structure, a fluorinated non-cyclic
vinyl ether monomer and a fluoroolefin.
8. The fluoropolymer according to claim 4, wherein the other
monomer units are monomer units formed by polymerization of at
least one member selected from tetrafluoroethylene,
perfluoro(butenyl vinyl ether) and
perfluoro(2,2-dimethyl-1,3-dioxole).
9. A fluoropolymer solution having the fluoropolymer as defined in
claim 4 dissolved in at least one fluorocarbon solvent selected
from perfluoro(2-butyltetrahydrofuran), perfluorooctane,
perfluorohexane, perfluoro(tributylamine),
perfluoro(tripropylamine), perfluorobenzene and
dichloropentafluoropropane.
10. An optical transmitter made by using the fluoropolymer as
defined in claim 4.
11. A plastic optical fiber having a core formed of a mixture
comprising the fluoropolymer as defined in claim 4 and a
fluorinated low molecular compound as a refractive index-increasing
agent.
12. The plastic optical fiber according to claim 11, wherein the
fluorinated low molecular compound is at least one compound
selected from perfluoro(triphenyltriazine),
perfluoro(1,3,5-triphenylbenzene) and a chlorotrifluoroethylene
oligomer.
13. The plastic optical fiber according to claim 11, wherein the
plastic optical fiber is a refractive index distribution type
optical fiber.
Description
TECHNICAL FIELD
[0001] The present invention relates to a fluorinated diene
compound having two unsaturated bonds, and a method for its
production, as well as a fluoropolymer, a fluoropolymer solution
employing it, an optical transmitter and a plastic optical
fiber.
BACKGROUND ART
[0002] As a fluorinated diene compound having two carbon-carbon
unsaturated double bonds (hereinafter referred to as unsaturated
bonds), CF.sub.2.dbd.CF(CF.sub.2).sub.kOCF.dbd.CF.sub.2 (wherein k
is an integer of from 1 to 3) is known (JP-A-1-143843). By
cyclopolymerization of this compound, it is possible to obtain an
amorphous polymer. Such a polymer has high elastic modulus, yield
and breaking elongation and is tough and excellent also in impact
resistance. Further, it has high transparency, and it is useful for
an optical material for e.g. optical fibers and optical waveguides.
However, the optical material employing this polymer has a low
glass transition temperature (T.sub.g) and thus has a drawback that
the optical characteristics are likely to change when it is used at
a high temperature for a long period of time. Accordingly, it is
desired to develop a material having a higher T.sub.g.
[0003] It is an object of the present invention to provide a novel
polymer which not only maintains the mechanical properties which
the above-mentioned amorphous polymer has, but also has a higher
glass transition temperature, so that it can be an optical resin
material having a low refractive index and being excellent in heat
resistance, and a novel fluorinated diene compound having two
unsaturated bonds, which presents such a polymer. Further, it is an
object of the present invention to provide a high performance light
transmitter and a plastic optical fiber, which have a low
refractive index and excellent heat resistance.
DISCLOSURE OF THE INVENTION
[0004] As a result of an extensive study, the present inventors
have produced a new specific fluorinated diene compound and further
have found it possible to accomplish the above objects by
polymerizing this fluorinated diene compound. That is, the present
invention provides the following:
[0005] 1. A fluorinated diene compound represented by the following
formula (1):
CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2 (1)
[0006] wherein R.sup.f is a perfluoroalkyl group.
[0007] 2. The fluorinated diene compound, wherein R.sup.f is a
trifluoromethyl group.
[0008] 3. A method for producing a fluorinated diene compound
represented by the following formula (1), characterized in that a
dehalogenation reaction is carried out at halogen atoms other than
fluorine atoms in at least one compound selected from a compound
represented by the following formula (2) and a compound represented
by the following formula (3):
CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2 (1)
CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2
(2)
CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCFZ.sup.3CF.sub.2Z.sup.4
(3)
[0009] wherein R.sup.f is a perfluoroalkyl group, and each of
Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 which are independent of one
another, is a halogen atom other than a fluorine atom.
[0010] 4. A fluoropolymer comprising monomer units formed by
cyclopolymerization of a fluorinated diene compound represented by
the formula (1), or monomer units formed by cyclopolymerization of
a fluorinated diene compound represented by the formula (1) and
monomer units formed by polymerization of other monomer
polymerizable with the fluorinated diene compound represented by
the formula (1):
CF.sub.2.dbd.CFCF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2 (1)
[0011] wherein R.sup.f is a perfluoroalkyl group.
[0012] 5. The fluoropolymer, wherein R.sup.f is a trifluoromethyl
group.
[0013] 6. The fluoropolymer, wherein the monomer units formed by
the cyclopolymerization of the fluorinated diene monomer
represented by the formula (1), are monomer units represented by
any one of the following formulae, wherein R.sup.f is as defined
above: 1
[0014] 7. The fluoropolymer, wherein the monomer units of other
polymerizable monomer are monomer units formed by polymerization of
at least one member selected from a fluorinated diene which is
cyclopolymerizable, other than the fluorinated diene compound
represented by the formula (1), a monomer having a fluorinated
aliphatic cyclic structure, a fluorinated non-cyclic vinyl ether
monomer and a fluoroolefin.
[0015] 8. The fluoropolymer, wherein the other monomer units are
monomer units formed by polymerization of at least one member
selected from tetrafluoroethylene, perfluoro(butenyl vinyl ether)
and perfluoro(2,2-dimethyl-1,3-dioxole).
[0016] 9. A fluoropolymer solution having the fluoropolymer
dissolved in at least one fluorocarbon solvent selected from
perfluoro(2-butyltetrahyd- rofuran), perfluorooctane,
perfluorohexane, perfluoro(tributylamine),
perfluoro(tripropylamine), perfluorobenzene and
dichloropentafluoropropan- e.
[0017] 10. An optical transmitter made by using the
fluoropolymer.
[0018] 11. A plastic optical fiber having a core formed of a
mixture comprising the fluoropolymer and a fluorinated low
molecular compound as a refractive index-increasing agent.
[0019] 12. The plastic optical fiber, wherein the fluorinated low
molecular compound is at least one compound selected from
perfluoro(triphenyltriazine), perfluoro(1,3,5-triphenylbenzene) and
a chlorotrifluoroethylene oligomer.
[0020] 13. The plastic optical fiber, wherein the plastic optical
fiber is a refractive index distribution type optical fiber.
BEST MODE FOR CARRYING OUT THE INVENTION
[0021] The fluorinated diene compound of the present invention is a
compound represented by the formula (1) (hereinafter, the compound
represented by the formula (1) may be referred to also as the
compound (1), and compounds represented by other formulae may
likewise be referred to.). In the formulae, R.sup.f represents a
perfluoroalkyl group.
[0022] The perfluoroalkyl group (hereinafter, the perfluoroalkyl
group may be referred to as a R.sup.f group) is a group having all
of hydrogen atoms of an alkyl group substituted by fluorine atoms.
The structure of the R.sup.f group may, for example, be a linear
structure, a branched structure, a cyclic structure or a structure
having a partially cyclic structure.
[0023] As the R.sup.f group having a linear structure, a R.sup.f
group having from 1 to 8 carbon atoms, is preferred, and it may,
for example, be --CF.sub.3, --CF.sub.2CF.sub.3, -nC.sub.3F.sub.7,
-nC.sub.4F.sub.9, -nC.sub.5F.sub.11, -nC.sub.6F.sub.13,
-nC.sub.7F.sub.15 or -nC.sub.8F.sub.17, and particularly preferred
is --CF.sub.3.
[0024] As the R.sup.f group having a branched structure,
--CF(CF.sub.3).sub.2, -isoC.sub.4F.sub.9, -secC.sub.4F.sub.9 or
-tertC.sub.4F.sub.9 may, for example, be mentioned.
[0025] As R.sup.f having a cyclic structure (i.e. a
perfluorocycloalkyl group), a perfluorocyclopropyl group, a
perfluorocyclobutyl group, a perfluorocyclopentyl group, a
perfluorocyclohexyl group or a group having a perfluoroalkyl group
having a linear structure or branched structure bonded to a carbon
atom constituting the ring of such a group, may be mentioned.
[0026] As the R.sup.f group having a partially cyclic structure, a
group having perfluorinated an alkyl group having a linear
structure substituted by a cycloalkyl group, or a group having
perfluorinated an alkyl group having a branched structure
substituted by a cycloalkyl group may be mentioned, and, for
example, a perfluoro(cyclohexylmethyl) group or a
perfluoro(cyclohexylethyl) group is preferred.
[0027] R.sup.f in the compound (1) of the present invention is
particularly preferably a trifluoromethyl group.
[0028] The following compounds may be mentioned as specific
examples of the compound (1) of the present invention.
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2CF.dbd.CF.sub.2
CF.sub.2.dbd.CFCF(OCF.sub.2CF.sub.3) CF.sub.2OCF.dbd.CF.sub.2
CF.sub.2.dbd.CFCF(OCF.sub.2CF.sub.2CF.sub.3)CF.sub.2OCF.dbd.CF.sub.2
CF.sub.2.dbd.CFCF(OCF.sub.2
CF.sub.2CF.sub.2CF.sub.3)CF.sub.2OCF.dbd.CF.su- b.2
CF.sub.2.dbd.CFCF(OCF(CF.sub.3).sub.2)CF.sub.2OCF.dbd.CF.sub.2
CF.sub.2.dbd.CFCF(OCF.sub.2CF(CF.sub.3).sub.2)CF.sub.2OCF.dbd.CF.sub.2
CF.sub.2.dbd.CFCF (OC(CF.sub.3).sub.3)CF.sub.2OCF.dbd.CF.sub.2
[0029] The fluorinated diene compound of the present invention is
preferably produced by a method wherein a dehalogenation reaction
is carried out at halogen atoms other than fluorine atoms in at
least one compound selected from a compound represented by the
following formula (2) and a compound represented by the following
formula (3):
CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCF.dbd.CF.sub.2
(2)
CF.sub.2Z.sup.1CFZ.sup.2CF(OR.sup.f)CF.sub.2OCFZ.sup.3CF.sub.2Z.sup.4
(3)
[0030] In the above formulae, R.sup.f is a perfluoroalkyl group
corresponding to R.sup.f in the formula (1).
[0031] Further, each of Z.sup.1, Z.sup.2, Z.sup.3 and Z.sup.4 which
are independent of one another, is a halogen atom other than a
fluorine atom, and may, for example, be a chlorine atom, a bromine
atom or an iodine atom, preferably a chlorine atom or a bromine
atom, particularly preferably each being a chlorine atom. By the
dehalogenation of such halogen atoms, a double bond will be formed,
whereby a fluorinated diene compound represented by the formula (1)
will be formed.
[0032] The dehalogenation in the method for producing a fluorinated
diene compound of the present invention, is preferably carried out
by having a dehalogenating agent reacted in a polar solvent. The
dehalogenating agent is a reactive agent which reacts with halogen
atoms in a substrate to withdraw the halogen atoms. Such a
dehalogenating agent may, for example, be zinc, sodium, magnesium,
tin, copper, iron or other metals. Zinc is particularly preferred
from the viewpoint of such a reaction condition that a relatively
low reaction temperature can be thereby employed.
[0033] As the polar solvent, an organic polar solvent such as
dimethylformamide, 1,4-dioxane, diglime or methanol, or water, is
preferred.
[0034] The amount of the dehalogenating agent is preferably from 1
to 20 times by mol, particularly preferably from 1 to 10 times by
mol, especially preferably from 2 to 10 times by mol, based on the
total amount of the compound (2) and/or the compound (3) to be used
for the reaction. The reaction temperature is usually from 40 to
100.degree. C., preferably from 50 to 80.degree. C. The
dehalogenation reaction is usually carried out by dropwise adding
the compound (2) in the presence of the dehalogenating agent and
the solvent. Isolation of the reaction product is preferably
carried out by withdrawing the reaction product from the reaction
system quickly after the reaction, by reactive distillation.
[0035] As a preferred embodiment of the compound (2) herein R.sup.f
is a trifluoromethyl group and each of Z.sup.1 and Z.sup.2 is a
chlorine atom, the following compound (2-1) can be obtained by
pyrolyzing the compound (2-2). This compound (2-2) can be
synthesized by adding hexafluoropropylene oxide to the compound
(2-3):
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2 (2-1)
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCF(CF.sub.3)COF (2-2)
CF.sub.2ClCFClCF(OCF.sub.3)COF (2-3)
[0036] The compound (2-3) is preferably produced by the following
method 1 or 2.
[0037] Method 1:
[0038] A method wherein the following compound (A) and the
following compound (B) are subjected to an esterification reaction
to form the following compound (C), the compound (C) is fluorinated
to form the following compound (D), and the compound (D) is
subjected to decomposition of the ester bond.
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OH (A)
R.sup.f2COX (B)
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOR.sup.f2 (C)
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCOR.sup.f2 (D)
[0039] In the above formulae, R.sup.f2 is a perfluoro monovalent
saturated organic group, and X is a halogen atom.
[0040] Method 2:
[0041] A method wherein the following compound (A.sup.1) is reacted
with the following compound (B) for esterification to form the
following compound (C.sup.1), the compound (C.sup.1) is chlorinated
to form the following compound (C), the compound (C) is fluorinated
to form the following compound (D), and the compound (D) is
subjected to decomposition of the ester bond.
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OH (A.sup.1)
R.sup.f2COX (B)
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCOR.sup.f2 (C.sup.1)
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOR.sup.f2 (C)
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCOR.sup.f2 (D)
[0042] In the above formulae, X is a halogen atom, and R.sup.f2 is
a perfluoro monovalent saturated organic group.
[0043] R.sup.f2 is preferably a perfluoroalkyl group, a
perfluoro(etheric oxygen atom-containing alkyl) group, a
perfluoro(partially chloroalkyl) group, or a perfluoro(partially
chloro(etheric oxygen atom-containing alkyl)) group, particularly
preferably a perfluoro(partially chloro(etheric oxygen
atom-containing alkyl)) group, especially preferably
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2--.
[0044] As specific examples of R.sup.f2, the following groups may
be mentioned, wherein n is an integer of from 1 to 9, r is an
integer of from 0 to 10, each of m and p is an integer of at least
0, preferably an integer of from 0 to 10, and k is an integer of at
least 1, preferably an integer of from 1 to 10.
[0045] CF.sub.3--,
[0046] CF.sub.3(CF.sub.2).sub.n--,
[0047] CF.sub.3(CF.sub.2).sub.mO(CF.sub.2).sub.k--,
[0048] CF.sub.3(CF.sub.2).sub.mOCF(CF.sub.3)--
[0049] CF.sub.2ClCFCl(CF.sub.2).sub.p--
[0050] CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2--,
[0051] CF.sub.2ClCFClCF(O(CF.sub.2).sub.rCF.sub.3)CF.sub.2--
[0052] Further, as R.sup.f2, CF.sub.2ClCFClCF(OCF.sub.3)--is
preferred.
[0053] X is a fluorine atom, a chlorine atom, a bromine atom or an
iodine atom, preferably a fluorine atom, a chlorine atom or a
bromine atom, particularly preferably a fluorine atom.
[0054] In the above methods 1 and 2, the esterification reaction
can be carried out under conditions for a usual esterification
reaction. Such a reaction may be carried out by using a solvent
(hereinafter referred to as an esterification solvent), but it is
preferred not to use an esterification solvent, from the viewpoint
of the volume efficiency.
[0055] In the esterification reaction, HX will be formed as a
by-product. When X is a fluorine atom, HF will be formed as a
by-product, and as a HF scavenger, an alkali metal fluoride (such
as NaF, KF or the like) or a base such as a trialkylamine or
pyridine, may be present in the reaction system. In a case where
such a HF scavenger is employed, its amount is preferably from 1 to
10 times by mol, to the compound (B) or the compound (B.sup.1). In
a case where no such a HF scavenger is used, the reaction may be
carried out at a reaction temperature where HF can be vaporized,
and HF is discharged out of the system as carried by a nitrogen
stream.
[0056] The lower limit temperature for the esterification reaction
is, in a usual case, preferably at least -50.degree. C., and the
upper limit is preferably whichever is lower +100.degree. C. or the
boiling point of the esterification solvent. Further, the reaction
time may optionally be changed depending upon the supply rate of
the raw material and the amount of the compound to be used for the
reaction. The reaction pressure (the gauge pressure, the same
applies hereinafter) is preferably from 0 to 2 MPa.
[0057] In the method 2, the compound (C.sup.1) formed by the
esterification reaction, is chlorinated to form the compound (C).
The chlorination reaction can be carried out under the operational
and reaction conditions for a usual chlorination reaction by means
of a chlorinating agent. The chlorinating agent is preferably
chlorine (Cl.sub.2). In a case where chlorine is used, the amount
is preferably from 1 to 10 times by mol, particularly preferably
from 1 to 5 times by mol, to the compound (C.sup.1). The reaction
of the compound (C.sup.1) with the chlorinating agent may be
carried out by using a solvent (hereinafter referred to as a
chlorination solvent), but it is preferred not to use a
chlorination solvent from the viewpoint of the volume efficiency.
In a case where a chlorination solvent is employed, it is preferred
to employ a halogenated hydrocarbon solvent. The halogenated
hydrocarbon solvent may, for example, be dichloromethane or
chloroform. The amount of the chlorination solvent is preferably
from 0.5 to 5 times the mass of the compound (C.sup.1). Further,
the temperature for the chlorination reaction is preferably from
-78.degree. C. to +200.degree. C.
[0058] With respect to the compound (C) in the methods 1 and 2, a
fluorination reaction is then carried out. The fluorination
reaction may be carried out by an electrochemical fluorination
method (ECF method), a method for fluorination by means of cobalt
fluoride, or a method for a reaction with fluorine gas in a gas
phase, but such methods have various problems such that the yield
of the fluorinated reaction product is very small, a special
apparatus is required, the operation is difficult, etc.
Accordingly, in the present invention, it is preferred to employ a
liquid phase fluorination method wherein a reaction with fluorine
is carried out in a liquid phase, from the viewpoint of a high
yield, simplicity of the operation, etc. Now, the liquid phase
fluorination method will be described.
[0059] The fluorine content in the compound (C) is preferably
appropriately changed depending upon the type of the liquid phase
to be used for the fluorination reaction. The lower limit of the
fluorine content (the proportion of the total amount of fluorine
atoms to the molecular weight of the substrate to be fluorinated)
is usually preferably 10 mass %, particularly preferably 30 mass %.
Further, the upper limit is preferably 86 mass %, particularly
preferably 80 mass %.
[0060] Further, it is preferred to adjust the structure of R.sup.f2
so that the molecular weight of the compound (C) will be from 300
to 1000. It is preferred that the molecular weight is within the
above range, since the fluorination reaction in the liquid phase
can be carried out smoothly. If the molecular weight is too small,
the substrate to be fluorinated, tends to be easily vaporized,
whereby a decomposition reaction in a gas phase is likely to take
place during the fluorination reaction in the liquid phase. On the
other hand, if the molecular weight is too large, purification of
the substrate to be fluorinated tends to be difficult.
[0061] The following compounds may be mentioned as examples of the
compound (C) and the compound (C.sup.1) as substrates to be
fluorinated. Here, m in the following formulae is as defined
above.
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)O(CF.sub.2).sub.mCF.sub.-
3,
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF.sub.2CF(OCF.sub.3)CFClCF.sub.2Cl,
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)O(CF.sub.2).sub.mCF.sub-
.3,
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCOCF.sub.2CF(OCF.sub.3)CFClCF.sub.2Cl-
.
[0062] The liquid phase fluorination is preferably carried out by
introducing fluorine in the solvent constituting the liquid phase
and reacting it with the compound. As the fluorine, 100% fluorine
gas may be employed, or fluorine gas diluted with an inert gas may
be employed. As such an inert gas, nitrogen gas or helium gas is
preferred, and nitrogen gas is particularly preferred. The fluorine
gas content in the gas mixture of the inert gas and the fluorine
gas, is preferably at least 5 vol % from the viewpoint of the
efficiency, particularly preferably from 5 to 30 vol % from the
viewpoint of withdrawing chlorine or preventing migration of
chlorine.
[0063] As the solvent (hereinafter referred to as a fluorination
solvent), a solvent which essentially contains a C--F bond without
containing a C--H bond, is preferred. Further, a perfluoroalkane or
an organic solvent obtained by perfluorinating a known organic
solvent having in its structure at least one atom selected from a
chlorine atom, a nitrogen atom and an oxygen atom, is preferred.
Further, as the fluorination solvent, it is preferred to employ a
solvent having a high solubility of the compound (C), and it is
particularly preferred to employ a solvent capable of dissolving at
least 1 mass %, particularly preferably at least 5 mass %, of the
compound (C), based on the total amount of the solvent and the
compound (C).
[0064] Examples of such a fluorination solvent include the compound
(D) as a product of a fluorination reaction, the compound (B),
perfluoroalkanes (trade name: FC-72, etc.), perfluoroethers (trade
name: FC-75, FC-77, etc.), perfluoropolyethers (trade name: KRYTOX,
FOMBLIN, GALDEN, DEMNUM, etc.), chlorofluorocarbons (trade name:
FLON LUBE), chlorofluoropolyethers, perfluoroalkylamines (such as
perfluorotrialkylamine, etc.), and inert fluids (trade name:
FLUORINERT). Among them, the compound (D) is preferred as the
fluorination solvent. When the compound (D) is used, there will be
an advantage that post treatment after the reaction may be easy.
The amount of the fluorination solvent is preferably at least 5
times by mass, particularly preferably from 10 to 100 times by
mass, relative to the compound (C).
[0065] The reaction system for the liquid phase fluorination
reaction is preferably a batch system or a continuous system. From
the viewpoint of the yield and selectivity of the reaction, the
reaction system is preferably the following system 2. Further, as
the fluorine gas, one diluted with an inert gas such as nitrogen
gas may be employed either in a case where the reaction is carried
out by a batch system or a case where the reaction is carried out
by a continuous system. The following systems may be mentioned as
methods for the fluorination reaction by a continuous system.
[0066] System 1
[0067] A method wherein into a reactor, the compound (C) and the
fluorination solvent are charged, and stirring is initiated. Then,
the reaction is carried out while continuously supplying fluorine
gas into the fluorination solvent at the prescribed reaction
temperature and reaction pressure.
[0068] System 2
[0069] A method wherein into a reactor, the fluorination solvent is
charged and stirred, and then the compound (C) and fluorine gas are
continuously and simultaneously supplied into the fluorination
solvent in a prescribed molar ratio at a predetermined reaction
temperature and reaction pressure.
[0070] When supplying the compound (C), it may or may not be
diluted with the fluorination solvent. In a case where it is
diluted, the amount of the fluorination solvent to the mass of the
compound (C) is preferably adjusted to be at least 5 times,
particularly preferably at least 10 times.
[0071] In the liquid phase fluorination reaction, in order to let
the fluorination reaction proceed efficiently, it is preferred to
charge fluorine gas so that at a later stage of the reaction, the
amount of fluorine will be always excess in equivalent to hydrogen
atoms present in the compound (C) and it is particularly preferred
to charge fluorine gas so that it will be at least 1.5 times by
equivalent (i.e. at least 1.5 times by mol), from the viewpoint of
the selectivity. The amount of fluorine is preferably maintained to
be always in excess from the initiation to the end of the
reaction.
[0072] The reaction temperature for the liquid phase fluorination
reaction is preferably at least -60.degree. C. and at most the
boiling point of the compound (C). It is particularly preferably
from -50.degree. C. to +100.degree. C. from the viewpoint of the
yield by the reaction, the selectivity and the industrial operation
efficiency, and it is especially preferably from -20.degree. C. to
+50.degree. C. from the viewpoint of withdrawing chlorine or
preventing migration of chlorine. The reaction pressure for the
fluorination reaction is not particularly limited, and it is
particularly preferably from atmospheric pressure to 2 MPa (gauge
pressure, and the pressure will hereinafter be represented by a
gauge pressure unless otherwise specified) from the viewpoint of
the yield by the reaction, the selectivity and the industrial
operation efficiency.
[0073] Further, in the liquid phase fluorination, it is preferred
to let a C--H bond-containing compound be present in the reaction
system, or to carry out radiation with ultraviolet rays. For
example, it is preferred to add the C--H bond-containing compound
to the action system or to carry out irradiation with ultraviolet
rays at a later stage of the fluorination reaction, whereby
hydrogen atoms present in the compound C), which are hardly
fluorinated, can efficiently be fluorinated, and the conversion can
remarkably be improved. The time for irradiation with ultraviolet
rays s preferably from 0.1 to 3 hours.
[0074] The C--H bond-containing compound is preferably an organic
compound other than the compound (C), particularly preferably an
aromatic hydrocarbon, especially preferably benzene, toluene or the
like. The amount of the C--H bond-containing compound is preferably
from 0.1 to 10 mol %, particularly preferably from 0.1 to 5 mol %,
based on the hydrogen atoms in the compound (C).
[0075] The C--H bond-containing compound is preferably added in a
state where fluorine is present in the reaction system. Further, in
a case where the C--H bond-containing compound is added, the
reaction system is preferably pressurized. The pressurizing
pressure is preferably from 0.01 to 5 MPa.
[0076] The liquid phase fluorination reaction is carried out until
hydrogen atoms in the compound (C) are perfluorinated. In the
liquid phase fluorination reaction, hydrogen atoms are replaced by
fluorine atoms, and in a case where an unsaturated bond is present,
fluorine atoms will be added to the unsaturated bond portion.
[0077] In the liquid phase fluorination reaction, HF will be formed
as a by-product. In order to remove HF formed as a by-product, it
is preferred to let a HF scavenger be coexistent in the reaction
system or to contact a HF scavenger and the discharge gas at the
gas outlet of the reactor. As such a HF scavenger, a base such as
an alkali metal fluoride (such as NaF, KF or the like) is lo
preferred, and such a base may be present in the reaction system.
As the HF scavenger, NaF is particularly preferred.
[0078] In a case where the HF scavenger is incorporated in the
reaction system, its amount is preferably from 1 to 20 times by
mol, more preferably from 1 to 5 times by mol, to the total amount
of hydrogen atoms present in the compound (C). In a case where the
HF scavenger is disposed at the gas outlet of the reactor, it is
preferred to install (a) a cooler (maintained to be preferably from
10.degree. C. to room temperature, particularly preferably at about
20.degree. C.), (b) a packed layer of the HF scavenger such as NaF
pellets, and (c) a cooler (maintained to be preferably from
-78.degree. C. to +10.degree. C., more preferably from -30.degree.
C. to 0.degree. C.) in series in the order of (a)-(b)-(c). Further,
a liquid-returning line may be installed to return a condensed
liquid from the cooler (c) to the reactor.
[0079] Then, the compound (D) is subjected to a decomposition
reaction of the ester bond to obtain the desired compound
(2-3).
[0080] The decomposition reaction is a reaction to break
--CF.sub.2OCO-- to form two --COF groups. Such a reaction is
preferably carried out by a pyrolysis reaction or by a
decomposition reaction carried out in the presence of a
nucleophilic agent or an electrophilic agent.
[0081] The pyrolysis reaction can be carried out by heating the
compound (D). The reaction system for the pyrolysis reaction is
preferably selected depending upon the boiling point and stability
of the compound (D).
[0082] For example, for a pyrolysis reaction in a case where the
compound (D) is a compound which is easily vaporized, it is
possible to employ a vapor phase pyrolysis method wherein
decomposition is carried out in a vapor phase continuously, and the
outlet gas containing the obtained compound (2-3) is condensed and
recovered. The reaction temperature for the vapor phase pyrolysis
method is preferably from 50 to 350.degree. C., particularly
preferably from 50 to 300.degree. C., especially preferably from
150 to 250.degree. C. Further, in the reaction system, an inert gas
which is not directly involved in the reaction, may be present. As
such an inert gas, nitrogen gas or carbon dioxide gas may, for
example, be mentioned. The inert gas is preferably incorporated in
an amount of from about 0.01 to 50 vol %, based on the compound
(D). If the amount of the inert gas to be incorporated, is large,
the recovery of the product may sometimes decrease.
[0083] On the other hand, for a pyrolysis reaction in a case where
the compound (D) is a hardly vaporizable compound, it is preferred
to employ a liquid phase pyrolysis method wherein the liquid is
heated in the state of liquid in the reactor. The reaction pressure
in such a case is not limited. In a usual case, products formed by
decomposition of the ester bond have lower boiling points.
Accordingly, it is preferred to carry out the reaction while
continuously withdrawing the low boiling point products by means of
a reactor equipped with a distillation column. Otherwise, a method
may be employed wherein the products are withdrawn from the reactor
all at once after completion of the heating. The reaction
temperature for such a liquid phase pyrolysis method is preferably
from 50 to 300.degree. C., particularly preferably from 80 to
250.degree. C.
[0084] In a case where pyrolysis is carried out by a liquid phase
pyrolysis method, it may be carried out in the absence of a solvent
or in the presence of a solvent (hereinafter referred to as a
decomposition reaction solvent). However, it is preferred to carry
out the reaction in the absence of any solvent. In a case where the
decomposition reaction solvent is employed, the solvent is not
particularly limited so long as it is a solvent which does not
react with the compound (D) and is compatible with the compound (D)
and which does not react with the compound (2-3). Further, as the
decomposition reaction solvent, it is preferred to select one which
can easily be separated at the time of purification of the
product.
[0085] As a specific example of the decomposition reaction solvent,
an inert solvent such as a perfluorotrialkylamine or
perfluoronaphthalene, or a chlorotrifluoroethylene oligomer (such
as FLON LUBE, trade name, manufactured by Asahi Glass Company,
Limited) having a high boiling point among chlorofluorocarbons, is
preferred. Further, the decomposition reaction solvent is
preferably used in an amount of from 10 to 1000 mass %, based on
the compound (D).
[0086] Further, the compound (D) may be subjected to decomposition
of the ester bond by reacting it with a nucleophilic agent or an
electrophilic agent in a liquid phase. In such a case, the reaction
may be carried out in the absence of any solvent or in the presence
of a decomposition reaction solvent. The nucleophilic agent is
preferably a fluorine ion (F.sup.-), particularly preferably a
fluorine ion derived from an alkali metal fluoride. As such an
alkali metal fluoride, NaF, NaHF.sub.2, KF or CsF is preferred, and
particularly preferred is NaF. By carrying out the pyrolysis
reaction in the presence of NaF, it is possible to carry out the
pyrolysis reaction at a low temperature, whereby it is possible to
prevent a decomposition reaction of the compound.
[0087] The nucleophilic agent to be used at the initial stage of
the reaction, is preferably in a catalytic amount, but may be used
in excess. The amount of the nucleophilic agent is preferably from
1 to 500 mol %, particularly preferably from 10 to 100 mol %,
especially preferably from 5 to 50 mol %, based on the compound
(D). The lower limit of the reaction temperature is preferably at
least -30.degree. C., and the upper limit is whichever is lower the
boiling point of the solvent or the boiling point of the compound
(D), and usually, it is particularly preferably from -20.degree. C.
to +250.degree. C. The decomposition reaction is preferably carried
out by means of a reactor equipped with a distillation column.
[0088] In the decomposition reaction of the ester bond, together
with the compound (2-3), the compound (B) represented by the
formula R.sup.f2COX, will be formed.
[0089] The compound (B) wherein R.sup.f2 is
CF.sub.2ClCFClCF(OCF.sub.3)CF.- sub.2--, is the same as the
compound of the formula (2-3), whereby no separation operation of
the formed product is required. However, in a case where R.sup.f2
is a group other than CF.sub.2ClCFClCF(OCF.sub.3)CF.s- ub.2--, it
is preferred to separate the compound (B) in the product. And, such
a compound (B) is preferably reused as a compound (B) to be reacted
with the compound (A) or the compound (A.sup.1).
[0090] The reaction for adding hexafluoropropylene oxide to the
compound (2-3) to obtain the compound (2-2), is preferably carried
out by reacting a metal fluoride to the compound (2-3) in a solvent
and reacting it with hexafluoropropylene oxide. The reaction
temperature for the reaction is preferably at most 50.degree. C.,
particularly preferably from 5 to 25.degree. C. The metal fluoride
may, for example, be potassium fluoride, cesium fluoride, sodium
fluoride or silver fluoride. The solvent for the reaction is
preferably an ether solvent or an aprotic polar solvent. The
reaction pressure of hexafluoropropylene oxide is preferably from 0
to 1 MPa, particularly preferably from 0.1 to 0.5 MPa.
[0091] Further, the compound (2-2) can be synthesized from the
compound (2-4) by the method disclosed in WO01/46093. Namely, the
compound (2-4) is reacted with the compound (2-5) to obtain a
compound (2-6). Further, the compound (2-6) is contacted with
chlorine gas to obtain a compound (2-7). The compound (2-7) is
subjected to liquid phase fluorination to obtain the compound
(2-2).
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCF(CF3)COF (2-2)
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCH(CH.sub.3)CH.sub.2OH
(2-4)
R.sup.f3COF (2-5)
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCH(CH.sub.3)CH.sub.2OCOR.sup.f3
(2-6)
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCH(CH.sub.3)CH.sub.2OCOR.sup.f3
(2-7)
[0092] In the above formulae, R.sup.f3 is preferably a fluoroalkyl
group, a fluoro(partially chloroalkyl) group, a fluoro(hetero
atom-containing alkyl) group or a fluoro(partially chloro(hetero
atom-containing alkyl)) group, particularly preferably such a group
which is perfluorinated.
[0093] The compound (2-2) will then be pyrolyzed to obtain the
compound (2-1). The pyrolysis can be carried out by a method of
directly pyrolyzing the compound (2-2), or a method of converting
the compound (2-2) to an alkali salt of the corresponding
carboxylic acid, followed by pyrolysis. Further, it is also
possible to employ a method wherein the active group (--COF) in the
compound (2-2) is converted to a practically stable group, which is
then converted to an alkali salt of the carboxylic acid, followed
by pyrolysis. As such a method, a method may, for example, be
mentioned wherein the compound (2-2) is reacted with an alkanol to
convert it to an alkyl ester of the corresponding carboxylic acid,
which is then converted to an alkali salt, followed by
pyrolysis.
[0094] In a case where the compound (2-2) is directly pyrolyzed, it
is preferred that the compound (2-2) is vaporized, then if
necessary, diluted with an inert gas such as nitrogen gas, and
contacted with a solid basic salt or glass beads at a high
temperature. The reaction temperature is usually from 200 to
500.degree. C., particularly preferably from 250 to 350.degree. C.
As the solid basic salt, sodium carbonate, potassium carbonate or
sodium phosphate may, for example, be used, and sodium carbonate is
particularly preferred.
[0095] Whereas, in a case where the compound (2-2) is converted to
an alkali metal salt of the corresponding carboxylic acid and then
pyrolyzed, it is preferred firstly to react the compound (2-2) with
an alkali metal hydroxide to form an alkali metal salt of the
carboxylic acid. The pyrolysis reaction of this alkali metal salt
is preferably carried out from 100 to 300.degree. C., particularly
preferably from 150 to 250.degree. C. By the pyrolysis reaction,
the compound (2-1) will be obtained. The pyrolysis reaction of an
alkali metal salt of the carboxylic acid is preferred, since it can
be carried out at a low temperature as compared with the method of
carrying out the pyrolysis directly, and the yield is also high.
The production of the alkali metal salt of the carboxylic acid is
preferably carried out by using water or an alcohol as a solvent,
and it is preferred that the obtained alkali metal salt is
sufficiently dried and then pyrolyzed. Further, as the alkali metal
salt, a sodium salt or a potassium salt may be mentioned, and a
potassium salt is preferred, since it can be pyrolyzed at a lower
temperature.
[0096] Further, the fluorinated diene compound (1) of the present
invention can be obtained also by carrying out dehalogenation at
halogen atoms other than fluorine atoms of the compound (3). A
compound (3-1) as a preferred embodiment of the compound (3)
wherein R.sup.f is a trifluoromethyl group, and Z.sup.1, Z.sup.2,
Z.sup.3 and Z are chlorine atoms, can be produced as follows.
Namely, a compound (2-3) is esterified to produce a compound (3-2)
(wherein R is an alkyl group). Otherwise, the compound (3-2) may
also be obtained by ester exchange of the above-mentioned compound
(D) and an alkanol represented by the formula ROH (wherein R is as
defined above). Further, the compound (3-2) is reduced to obtain a
compound (3-3). Then, this compound is reacted with an alkali metal
hydride or an alkali metal to form a metal alkoxide (3-3a) (wherein
M is an alkali metal atom), which is then reacted with
tetrafluoroethylene to obtain a compound (3-4). This compound (3-4)
is further contacted with chlorine gas to add chlorine atoms to the
unsaturated bond thereby to produce a compound (3-5). Finally,
hydrogen atoms in this compound (3-5) are all replaced by fluorine
atoms by liquid phase fluorination to obtain the compound
(3-1).
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCFClCF.sub.2Cl (3-1)
CF.sub.2ClCFClCF(OCF.sub.3)COF (2-3)
CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2R (3-2)
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OH (3-3)
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OM (3-3a)
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCF.dbd.CF.sub.2 (3-4)
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCFClCF.sub.2Cl (3-5)
[0097] The esterification of the compound (2-3) can be carried out
by dropwise adding the acid fluoride represented by the formula
(2-3) into an alkanol represented by the formula ROH. The
temperature for the reaction is preferably from 0.degree. C. to
20.degree. C. R is preferably a C.sub.1-4 alkyl group. On the other
hand, in a case where the compound (3-2) is produced by the ester
exchange, usual ester exchange reaction conditions can be
applied.
[0098] Then, the compound (3-2) is reduced to produce the compound
(3-3). The reduction reaction is preferably carried out, for
example, by sodium boron hydride or lithium aluminum hydride. The
reaction temperature is preferably from 0.degree. C. to 20.degree.
C. The reduction reaction is preferably carried out in the presence
of a reaction solvent, and as the reaction solvent, an alcohol or a
non-cyclic or cyclic ether solvent may be mentioned. Specifically,
methanol, ethanol, isopropanol, n-butanol, t-butanol, diethyl
ether, methyl t-butyl ether, tetrahydrofuran, dioxane, monoglime,
diglime, triglime or tetraglime may, for example, be used. These
solvents may be used alone or in combination as a mixture of an
optional ratio. By mixing the solvent, it is possible to control
the reaction. In the case of a mixture, it is preferred to employ
an ether solvent in an amount of from 1 to 10 times by volume, to
an alcohol. To control a side reaction, it is particularly
preferred to use diethyl ether or tetrahydrofuran as mixed in an
amount of from 1 to 2 times by volume to ethanol.
[0099] Then, the compound (3-3) is reacted with an alkali metal
hydride or an alkali metal (such as sodium) to obtain the compound
(3-3a). The temperature for such a reaction is preferably from
0.degree. C. to 20.degree. C. The alkali metal atom in the alkali
metal hydride may, for example, be sodium, lithium, potassium or
cesium. Such a reaction may be carried out in the presence of a
reaction solvent, and as such a reaction solvent, a non-cyclic or
cyclic ether solvent or an aprotic polar solvent may be employed.
Specifically, diethyl ether, methyl t-butyl ether, tetrahydrofuran,
dioxane, monoglime, diglime, triglime, tetraglime, acetonitrile,
benzonitrile, sulfolane, dimethylacetamide or dimethylsulfoxide
may, for example, be used. The formed compound (3-3a) is preferably
used for the next reaction together with the reaction solvent,
without isolating it.
[0100] Then, tetrafluoroethylene is added to the compound (3-3a) to
obtain the compound (3-4). This reaction is preferably carried out
by transferring the reaction product containing the compound (3-3a)
as it contains the reaction solvent, to an autoclave and
introducing tetrafluoroethylene. The reaction temperature for the
reaction is preferably from -10 to +50.degree. C., particularly
preferably from 0 to +30.degree. C. The reaction pressure is
preferably from 0.5 to 3.5 MPa, particularly preferably from 1.0 to
2.2 MPa. Further, it is preferred to raise the reaction temperature
after completion of the introduction of tetrafluoroethylene, and
the temperature raised is preferably from 30 to 100.degree. C.,
particularly preferably from 50 to 70.degree. C. The reaction time
is preferably from 30 minutes to 120 hours, particularly preferably
from 5 hours to 10 hours.
[0101] Then, the compound (3-4) is chlorinated to obtain the
compound (3-5) having chlorine atoms introduced to the unsaturated
double bond of the vinyl ether. This reaction involves heat
generation, and it is accordingly preferred to carry out the
reaction while cooling the system. The reaction temperature for
this reaction is preferably adjusted from -50 to 100.degree. C.,
particularly preferably from -20 to 10.degree. C.
[0102] Then, the compound (3-5) is reacted with fluorine in a
liquid phase to obtain the compound (3-1). This can be carried out
in the same manner as the above-mentioned fluorination. And, the
compound (3-1) is subjected to the above-mentioned dehalogenation
reaction, whereby the compound (1) of the present invention can be
produced.
[0103] The fluorinated diene compound (1) of the present invention
is polymerizable, and is useful as a monomer for the production of
a fluoropolymer. This fluorinated diene compound (1) undergoes
cyclic polymerization alone by an action of a radical
polymerization initiator to form a polymer having monomer units
having fluorinated aliphatic cyclic structures in its main chain.
Further, the fluorinated diene compound (1) may be copolymerized
with another monomer.
[0104] Namely, the present invention presents a fluoropolymer
comprising monomer units formed by cyclopolymerization of the
fluorinated diene compound (1), or a fluoropolymer comprising
monomer units formed by cyclopolymerization of the fluorinated
diene compound (1) and monomer units formed by polymerization of
another monomer polymerizable with the fluorinated diene compound
(1). The proportion of the monomer units of the fluorinated diene
compound (1) contained in the fluoropolymer is preferably from 30
to 100 mol %, particularly preferably from 50 to 100 mol %, based
on the total monomer units. Further, the molecular weight of the
fluoropolymer is preferably from 500 to 1.times.10.sup.6,
particularly preferably from 500 to 5.times.10.sup.5.
[0105] The monomer units formed by cyclopolymerization of the
fluorinated diene compound (1) are preferably either one of monomer
units represented by the following formulae. The monomer units
present in the fluoropolymer may be of one type, or of two or more
types. 2
[0106] Another polymerizable monomer is not particularly limited so
long as it is a radically polymerizable monomer, and it may, for
example, be a fluorinated monomer other than the compound (1), a
hydrocarbon monomer or other monomer. For example, it may be an
olefin such as ethylene, a fluoroolefin such as
tetrafluoroethylene, a fluorinated vinyl ether monomer such as a
perfluoro(alkyl vinyl ether), a cyclopolymerizable fluorinated
diene (other than the fluorinated diene compound (1)) such as a
perfluoro(allyl vinyl ether) or a monomer having a fluorinated
aliphatic ring structure, such as
perfluoro(2,2-dimethyl-1,3-dioxole). As another polymerizable
monomer, at least one member selected from tetrafluoroethylene,
perfluoro(butenyl vinyl ether) and
perfluoro(2,2-dimethyl-1,3-dioxole) is particularly preferred. The
proportion of monomer units of another polymerizable monomer is
preferably from 0 to 70 mol %, particularly preferably from 0 to
50%, based on the total monomer units in the fluoropolymer. Such
another monomer may be used alone or in combination of two or more
types.
[0107] As the radical polymerization initiator to be used for
polymerization of the fluorinated diene compound (1), a
polymerization initiator commonly used for radical polymerization
of e.g. an azo compound, an organic peroxide or an inorganic
peroxide, may be used. Specifically, diisopropyl peroxydicarbonate,
an azo compound such as 2,2'-azobis(2-amidinopropane)
dihydrochloride, 4,4'-azobis(4-cyanopentano- ic acid),
2,2'-azobis(4-methoxy-2,3-dimethylvaleronitrile) or
1,1'-azobis(1-cyclohexanecarbonitrile), an organic peroxide such as
benzoyl peroxide, perfluorobenzoyl peroxide, perfluorononanoyl
peroxide or methyl ethyl ketone peroxide, or an inorganic peroxide
such as K.sub.2S.sub.2O.sub.8 or (NH.sub.4).sub.2S.sub.2O.sub.8,
may, for example, be mentioned.
[0108] The polymerization method is not particularly limited, and
it may, for example, be a polymerization wherein the fluorinated
diene compound (1) is directly polymerized (so-called bulk
polymerization), a solution polymerization wherein the fluorinated
diene compound (1) is dissolved in a fluorinated hydrocarbon, a
chlorinated hydrocarbon, a chlorinated fluorohydrocarbon, an
alcohol, a hydrocarbon or other organic solvents and polymerized, a
suspension polymerization wherein polymerization is carried out in
an aqueous medium, if necessary, in the presence of an organic
solvent, or an emulsion polymerization wherein polymerization is
carried out in an aqueous medium in the presence of an emulsifier.
The temperature and the pressure for the polymerization are not
particularly limited, and it is advisable to suitably set them
taking into consideration the boiling point of the fluorinated
diene compound, the heating source, removal of the polymerization
heat, etc. The polymerization temperature is usually preferably
from 0 to 200.degree. C., particularly preferably from 30 to
100.degree. C. The polymerization pressure may be a reduced
pressure or an elevated pressure, and it is practically preferably
from atmospheric pressure to about 10 MPa, more preferably from
atmospheric pressure to about 5 MPa.
[0109] The fluoropolymer of the present invention has
characteristics such that it is excellent in transparency, the
glass transition temperature is high, and the heat resistance is
high. By utilizing such characteristics, the fluoropolymer of the
present invention is useful by itself as an optical resin material
excellent in heat resistance, to be used for an optical fiber, an
optical waveguide or an optical transmitter such as a lens.
Further, the fluoropolymer of the present invention has
characteristics that it is optically transparent, and it has a low
refractive index as compared with a conventional transparent
fluorocarbon resin (such as CYTOP, trade name, manufactured by
Asahi Glass Company, Limited or Teflon AF, trade name, manufactured
by DuPont). By utilizing such characteristics, the fluoropolymer of
the present invention may be combined with a conventional
transparent fluorocarbon resin having a low refractive index and
use as a high performance optical device excellent in optical
transparency, such as an optical fiber or an optical waveguide.
[0110] Particularly, a plastic optical fiber comprising a core made
of a mixture comprising the fluoropolymer of the present invention
and a refractive index-increasing agent, and a clad made of the
fluoropolymer of the present invention, has excellent heat
resistance. Such a plastic optical fiber may be used as of a step
index type or a refractive index-distribution type, and it is
particularly preferably a plastic optical fiber of refractive
index-distribution type. As the above refractive index-increasing
agent, a fluorinated low molecular weight compound is preferred,
since the transparency of the obtainable mixture will be excellent.
As such a fluorinated low molecular weight compound,
perfluoro(triphenyltriazine), perfluoro(1,3,5-triphenylbenzene) or
chlorotrifluoroethylene oligomer may, for example, be preferably
mentioned. Such low molecular weight compounds may be used alone or
in combination as a mixture of two or more of them.
[0111] The following methods may be mentioned as the method for
producing a plastic optical fiber of refractive index-distribution
type.
[0112] For example, a method wherein a columnar molded product of
the fluoropolymer of the present invention is prepared so that at
the center axis portion, a refractive index-increasing agent is
present at a predetermined concentration, and the refractive
index-increasing agent is diffused in a radial direction from the
center axis portion by thermal diffusion to form a refractive index
distribution, whereupon the obtained columnar molded product is
used as a preform to form an optical fiber (JP-A-8-5848).
[0113] A method wherein a cylindrical molded product is prepared by
the fluoropolymer of the present invention, a predetermined amount
of a refractive index-increasing agent is introduced into the
center portion, followed by thermal diffusion to form a cylindrical
preform having a refractive index distribution, which is formed
into an optical fiber (JP-A-8-334633).
[0114] Further, the fluoropolymer of the present invention is
soluble in a fluorocarbon solvent such as
perfluoro(2-butyltetrahydrofuran), perfluorooctane,
perfluorohexane, perfluoro(tributylamine),
perfluoro(tripropylamine), perfluorobenzene or
dichloropentafluoropropane- . A solution having the fluoropolymer
of the present invention dissolved in such a solvent, is a
fluoropolymer solution useful for various applications. As an
application of such a solution, an application may, for example, be
mentioned wherein it is coated on a substrate such as a glass or
silicon wafer by a spin coating method or a spraying method, and
then the solvent is vaporized for drying to form a thin film. The
amount of the fluoropolymer contained in such a fluoropolymer
solution is preferably from 0.01 to 20 mass %, particularly
preferably from 0.1 to 10 mass %.
[0115] Further, the fluoropolymer of the present invention may be
subjected to heat treatment or fluorine gas treatment, whereby the
terminal groups can easily be substituted. And, by changing the
structure of terminal groups by the treating method, the adhesion
property to various substrates can be changed. For example,
carboxyl groups can be introduced to the terminals by heating the
fluoropolymer of the present invention at a temperature of at least
200.degree. C. in the presence of air, followed by treatment with
water. Otherwise, it is possible to remove reactive functional
groups at the terminals by reacting them with fluorine gas, whereby
it is possible to improve the thermal stability of the
fluoropolymer.
EXAMPLES
[0116] Now, the present invention will be described in further
detail with reference to Examples. However, it should be understood
that the present invention is by no means restricted by such
Examples. In the following, gas chromatography will be referred to
as GC, a nuclear magnetic resonance spectrum analysis as NMR, a gas
chromatography mass spectrum as GC-MS, tetramethylsilane as TMS,
1,1,2-trichlorotrifluoroethane as R-113, and
dichloropentafluoropropane as R-225. Further, the GC purity is
meant for the purity obtained from the peak area ratio by gas
chromatography. Further, the refractive index was measured by means
of Abbe's refractometer, and the glass transition temperature
(T.sub.g) was measured by means of a differential scanning
calorimetry (DSC).
Example 1
Preparation of
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)OCF.sub.-
2CF.sub.2CF.sub.3
[0117] CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OH (270 g) was charged
together with NaF (334 g) into a 2 L pressure resistant reactor
equipped with a reflux condenser having a cooling medium of
20.degree. C. circulated, and stirred at -10.degree. C.
[0118] While bubbling nitrogen gas in the reactor to discharge HF
formed as a by-product by the reaction, out of the system from the
upper reflux condenser, FCOCF(CF.sub.3)OCF.sub.2CF.sub.2CF.sub.3
(1055 g) was dropwise added over a period of 1.5 hours. At that
time, the temperature was adjusted so that the internal temperature
of the reactor became at most 0.degree. C. After completion of the
dropwise addition, stirring was carried out at 30.degree. C. for 18
hours to complete the reaction. After completion of the reaction,
NaF contained in the crude solution was filtered off to obtain a
crude product (981 g) (yield: 86.4%). As a result of the analysis
by NMR, formation of the above identified compound was
confirmed.
[0119] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm): 3.29 (s, 3H), 3.85 to 3.90 (m, 1H), 4.24 to 4.45 (m,
2H), 5.34 (s, 1H), 5.39 (d, J=8.4 Hz, 1H), 5.59 to 5.71 (m,
1H).
[0120] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.13, standard:
CFCl.sub.3) .delta. (ppm): -81.8 (3F), -82.6 (3F), -79.9 to -87.5
(2F), -130.2 (2F), -132.3 (1F).
Example 2
Preparation of
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)OCF.sub.2-
CF.sub.2CF.sub.3
[0121]
CH.sub.2.dbd.CHCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)OCF.sub.2CF.sub.-
2CF.sub.3 (981 g) obtained in Example 1, was charged into a 2 L
three-necked flask cooled to 0.degree. C. and equipped with a
Dimroth condenser, and with stirring at from -10 to 0.degree. C.,
chlorine gas was introduced at a rate of 0.8 g/min to carry out the
reaction. When 170 g of chlorine gas was introduced, the reaction
was terminated to obtain a crude liquid (1084 g).
[0122] The obtained crude liquid was purified by distillation under
a reduced pressure of from 0.8 to 0.9 kPa (absolute pressure) to
obtain a product (744 g). As a result of the analyses by NMR and
GC, it was confirmed that the above identified compound was formed
as a mixture of three types of diastereomers having a GC purity of
98%.
[0123] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm): 3.45 (d, J=1.5 Hz) and 3.47 (s) and 3.55 (d J=0.6
Hz) total 3H, 3.56 to 3.80 (m, 2H), 3.82 to 4.12 (m, 2H), 4.43 to
4.57 (m, 1H), 4.65 (dd, J=6.3 Hz, 11.4 Hz) and 4.89 (ddd, J=42.4
Hz, 12.0 Hz, 3.0 Hz) and 5.49 (q, J=5.1 Hz) total 1H.
[0124] .sup.19F-NMR (376.0 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm): -79.93 to -80.65 (1F), -81.72 to -81.80
(3F), -82.47 to -82.56 (3F), -86.46 to -87.22 (1F), -130.07 to
-130.19 (2F), -132.26 to -132.47 (1F).
Example 3
Preparation of
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCOCF(CF.sub.3)OCF.sub.2-
CF.sub.2CF.sub.3 By a Fluorination Reaction
[0125] Into a 3 L autoclave made of nickel,
CF.sub.3CF.sub.2CF.sub.2OCF(CF- .sub.3)CF.sub.2OCF(CF.sub.3)COF
(3523 g, hereinafter referred to as the solvent A) was charged,
stirred and maintained at 5.degree. C. At the gas outlet of the
autoclave, a condenser maintained at -10.degree. C. was installed.
Nitrogen gas was blown thereinto for 3.5 hours, and then fluorine
gas diluted with nitrogen gas to 20% (hereinafter referred to as
the diluted fluorine gas) was blown thereinto at a flow rate of
26.52 L/hr for one hour. Then, while supplying fluorine gas at the
same flow rate, a part (415 g) of
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3-
)OCF.sub.2CF.sub.2CF.sub.3 obtained in Example 2 was injected over
a period of 22.5 hours. The reaction crude liquid (261 g) was
withdrawn.
[0126] Then, while supplying the diluted fluorine gas at the same
flow rate,
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)OCF.sub.2CF.sub.2-
CF.sub.3 (642 g) was injected over a period of 22.0 hours. A
reaction crude liquid (533 g) was withdrawn.
[0127] Further, while supplying the diluted fluorine gas at the
same flow rate,
CH.sub.2ClCHClCH(OCH.sub.3)CH.sub.2OCOCF(CF.sub.3)OCF.sub.2CF.sub.2-
CF.sub.3 (471 g) was injected over a period of 22.8 hours. The
reaction crude liquid (270 g) was withdrawn.
[0128] Then, while supplying the diluted fluorine gas at the same
flow rate, the reaction temperature was adjusted at 25.degree. C.
for 22 hours. Then, nitrogen gas was blown thereinto for 3.0 hours.
The reaction crude liquid (3530 g) was recovered. As a result of
the analysis of the reaction crude liquid by GC-MS, it was found
that the solvent A and the above identified compound were obtained
as the main components. The reaction yield of the above identified
compound was 71%.
Example 4
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)COF (2-3) by a
Decomposition Reaction of an Ester Bond
[0129] Into a 300 mL four-necked flask equipped with a stirrer and
a reflux condenser,
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCOCF(CF.sub.3)OCF.s-
ub.2CF.sub.2CF.sub.3 (200 g, 0.31 mol) obtained in Example 3 was
charged together with KF powder (9.0 g, 0.155 mol), and while
stirring sufficiently, the mixture was heated in an oil bath at a
temperature of from 90 to 95.degree. C. for from 0.5 to 1 hour.
After confirming refluxing formed as the reaction proceeded, the
reaction system was brought to reduced pressure, and the formed
product was recovered by distilling it and withdrawing it from the
reaction system over a period of 5 hours. Further, the crude
product was distilled to obtain the above identified compound (74
g) having a GC purity of 99.9% (yield: 79%). From the NMR spectrum,
it was confirmed that the above identified compound is the main
component.
[0130] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm): 28.4, 28.0 (1F), -55.1, -55.4 (3F),
-61.6 to -63.9 (2F), -121.9, -123.9 (1F), -128.7, -129.0 (1F).
[0131] Boiling point: 62.degree. C./33.3 kPa (absolute
pressure).
Example 5
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCF(CF.sub.3)COF
(2-2)
[0132] Into an autoclave made of a hastelloy alloy and having an
internal capacity of 100 mL, KF (0.4 g, 7.14 mmol) was put, and
after reducing the pressure, CF.sub.2ClCFClCF(OCF.sub.3)COF
obtained in Example 4 (37 g, 0.12 mol) and tetraglime (10 g) were
charged and cooled with sufficient stirring, followed by stirring
for from 30 minutes to one hour while adjusting the internal
temperature to from -5.degree. C. to +50.degree. C. Then, the
autoclave was connected to a steel bottle of hexafluoropropylene
oxide, and hexafluoropropylene oxide (33 g) was added while
maintaining the internal temperature at at most 25.degree. C. and
the internal pressure at about 0.2 MPa, followed by stirring until
no decrease of the internal pressure was observed. Thereafter,
hexafluoropropylene oxide was purged, followed by stirring at
25.degree. C. for from 1 to 2 hours. Then, the autoclave was
opened, and the remaining solid was removed by filtration, followed
by phase separation to obtain a crude product. The crude product
was further distilled to obtain 5.9 g (yield: 10%) of pure
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCF(- CF.sub.3)COF.
[0133] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); 28.0, 27.8, 27.4 (1F), -52.2 to -53.0
(3F), -63.0 to -66.5 (2F), -79.5 to -81.5 (2F), -81.2, -81.4 (3F),
-128.1, -128.7 (1F), -129.2, -130.1 (1F), -131.4, -132.1 (1F).
Example 6-1
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2CH.sub.3
(3-2)
[0134] Into a 1 L four-necked flask made of glass and equipped with
a stirrer, a reflux condenser and a dropping funnel, methanol (120
g, 3.75 mol) was put and cooled until the internal temperature
became from 5 to 10.degree. C., and while sufficiently stirring,
CF.sub.2ClCFClCF(OCF.sub.-
3)CF.sub.2OCOCF(CF.sub.3)OCF.sub.2CF.sub.2CF.sub.3 (380 g, 0.59
mol) obtained in Example 3 was dropwise added while maintaining the
internal temperature at from 5 to 20.degree. C. Thereafter, while
bubbling nitrogen gas in the reactor to discharge HF formed as a
by-product by the reaction out of the system by an upper reflux
condenser, stirring was continued for a while at room temperature.
Then, deionized water (340 g) was added, followed by stirring
sufficiently and then by phase separation into two phases,
whereupon the product of the lower layer was withdrawn. Further,
the crude product was distilled to obtain 128 g of pure
CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2CH.sub.3 (yield: 67%)
Example 6-2
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2CH.sub.3
(3-2)
[0135] Using CF.sub.2ClCFClCF(OCF.sub.3)COF obtained in Example 4
(40 g, 0.12 mol) and methanol (10 g, 0.31 mol), in the same manner
as in Example 6-1, CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2CH.sub.3 was
obtained (36 g, yield: 94%).
[0136] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -55.1, -55.5 (3F), -61.8 to -64.4 (2F),
-123, -126 (1F), -129.3, -129.7 (1F).
[0137] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm); 3.96 (CH.sub.3).
[0138] Boiling point: 55.degree. C./2.7 kPa.
Example 7
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OH (3-3) BY a
Reduction Reaction
[0139] Into a 2 L four-necked flask made of glass and quipped with
a stirrer and a dropping funnel, sodium boron hydride (17 g, 0.46
mol), diethyl ether (230 g) and ethanol (200 g) were put, followed
by cooling until the internal temperature became from 5 to
10.degree. C. While maintaining the internal temperature at from 5
to 20.degree. C. with sufficient stirring,
CF.sub.2ClCFClCF(OCF.sub.3)CO.sub.2CH.sub.3 (150 g, 0.46 mol)
obtained in Example 6 was dropwise added. Thereafter, while
maintaining the internal temperature at from 5 to 20.degree. C.,
the reaction solution was stirred for from 2 to 3 hours. Then, 1
moL/L of hydrochloric acid (310 g) was added, followed by stirring
sufficiently, and extraction was carried out with diethyl ether.
The organic layer was separated and dried over magnesium sulfate,
whereupon diethyl ether was distilled off under reduced pressure.
The obtained crude product was purified by distillation to obtain
128 g (yield: 70%) of highly pure
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OH.
[0140] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -53.3, -53.8 (3F), -60.8 to -63.6 (2F),
-125.4, -126.7 (1F), -128.9, -129.3 (1F).
[0141] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm); 2.1 (OH), 4.0 to 4.3 (CH.sub.2).
[0142] Boiling point: 41.degree. C./0.7 kPa (absolute
pressure).
Example 8
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCF.dbd.CF.sub.2
(3-4)
[0143] Into a 2 L four-necked flask equipped with a stirrer and a
dropping funnel, sodium hydride (5.4 g, 0.13 mol) was charged, and
in an inert gas atmosphere, diethyl ether (140 mL) was charged.
Then, while adjusting the internal temperature from 0 to 5.degree.
C., CF.sub.2ClCFClCF(OCF.sub.3)C- H.sub.2OH (35 g, 0.12 mol)
obtained in Example 7 was slowly dropwise added. Thereafter, the
internal temperature was slowly raised to room temperature, and the
reaction was carried out:for 5 hours. Thereafter, the reaction
solution was transferred to a 2 L autoclave which was preliminarily
vacuumed, and introducing nitrogen to 0.5 MPa, followed by purging,
was repeated three times. Then, while maintaining the remaining
nitrogen pressure at 0.05 MPa, tetrafluoroethylene (47 g, 0.47 mol)
was slowly introduced little by little. After the charging, the
reaction temperature was raised to 70.degree. C. to raise the
internal pressure to 2.2 MPa, and the reaction was carried out for
from 5 to 10 hours until no more pressure decrease was observed.
Then, the reaction system was cooled, and remaining
tetrafluoroethylene was purged, whereupon the autoclave was
opened.
[0144] As post-treatment of the reaction solution, methanol (9.0 g)
and 1 moL/L of hydrochloric acid (140 g) were added, followed by
sufficient stirring, whereupon extraction with diethyl ether was
carried out, and the organic layer was separated and then, dried
over magnesium sulfate, and diethyl ether was distilled off under
reduced pressure.
[0145] The crude product thus obtained was purified by distillation
to obtain pure CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCF.dbd.CF.sub.2
(18 g, yield: 40%).
[0146] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -53.3, -53.5 (F.sup.e, 3F), -60.8 to
-63.6 (F.sup.i, 2F), -120.2 (F.sup.a, 1F, J.sub.ab=99 Hz), -124.7,
-126.0 (F.sup.g, 1F), -126.0 (F.sup.b, 1F, J.sub.bc=108 Hz),
-128.9, -129.1 (F.sup.d, 1F), -137.4 (F.sup.c, 1F, J.sub.ac=58
Hz).
[0147] Here, a to i in F.sup.a to F.sup.i, correspond to the
positions of fluorine atoms, as shown in the following formula:
3
[0148] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm); 4.4 to 4.7 (CH.sub.2).
[0149] Boiling point: 41.degree. C./1.3 kPa (absolute
pressure).
Example 9
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCFClCF.sub.2Cl
(3-5)
[0150] Into a 100 mL three-necked flask equipped with a stirrer and
a dry ice condenser,
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCF.dbd.CF.sub.2 (35 g, 92 mmol)
obtained in Example 8 was charged and cooled until the internal
temperature became within a range of from -25 to -20.degree. C.,
and while maintaining the internal temperature at -10.degree. C. to
+10.degree. C. with sufficient stirring, chlorine gas was blown
thereinto. When chlorine (7.4 g, 104 mmol) gas was introduced, the
introduction was stopped, and the crude product was recovered. The
crude product was further distilled to obtain pure
CF.sub.2ClCFClCF(OCF.sub.3)C- H.sub.2OCFClCF.sub.2Cl (38 g, yield:
95%).
[0151] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -53.3, -53.5 (3F), -60.8 to -63.6 (2F),
-69.2 (2F), -74.2, -74.5 (1F), -123.3 to -124.9 (1F), -128.9,
-129.0 (1F).
[0152] .sup.1H-NMR (300.4 MHz, solvent: CDCl.sub.3, standard: TMS)
.delta. (ppm); 4.4 to 4.7 (CH.sub.2)
[0153] Boiling point: 50.degree. C./0.7 kPa (absolute
pressure).
Example 10
Preparation of CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCFClCF.sub.2Cl
(3-1)
[0154] Into a 500 mL autoclave made of nickel, R-113 (312 g) was
charged, stirred and maintained at 25.degree. C. At the gas outlet
of the autoclave, a condenser maintained at 20.degree. C., a NaF
pellet-packed layer and a condenser maintained at -10.degree. C.
were installed in series. Further, a liquid-returning line was
installed to return the liquid condensed from the condenser
maintained at -10.degree. C., to the autoclave. Nitrogen gas was
supplied for 1.0 hour, and then, diluted fluorine gas was supplied
at a flow rate of 11.88 L/hr for one hour. Then, while supplying
fluorine gas at the same flow rate, a solution having
CF.sub.2ClCFClCF(OCF.sub.3)CH.sub.2OCFClCF.sub.2Cl (34 g, 75 mmol)
obtained in Example 9, dissolved in R-113 (195.3 g), was injected
over a period of 5.8 hours.
[0155] Then, while supplying fluorine gas at the same flow rate and
maintaining the reactor pressure at 0.15 MPa, a R-113 solution
having a benzene concentration of 0.01 g/ml was injected in an
amount of 9 ml while raising the temperature from 25.degree. C. to
40.degree. C., whereupon the benzene inlet of the autoclave was
closed, and stirring was continued for 0.3 hour. Then, while
maintaining the reactor pressure at 0.15 MPa and the internal
temperature of the reactor at 40.degree. C., the above-mentioned
benzene solution was injected in an amount of 6 ml, and stirring
was continued for 0.3 hour. Further, while maintaining the internal
temperature of the reactor at 40.degree. C., the above-mentioned
benzene solution was injected in an amount of 6 ml, and stirring
was continued for 0.3 hour. The same operation was repeated seven
times, and stirring was continued for further 0.7 hour. The total
amount of benzene injected was 0.595 g, and the total amount of
R-113 injected was 57 ml. Further, nitrogen gas was supplied for
1.0 hour. The desired product was quantified by .sup.19F-NMR
(internal standard: C.sub.6F.sub.6), whereby the yield of the above
identified compound was 85%. The crude product was further
distilled to obtain 30 g of pure CF.sub.2ClCFClCF(OCF.sub.3)CF.su-
b.2OCFClCF.sub.2Cl.
[0156] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -52.4, -52.8 (3F), -60.7 to -64.2 (2F),
-70.5 (2F), -76.5 (1F), -76.7 to -81.2 (2F) -127.7, -128.5 (1F),
-132.9, -133.7 (1F).
[0157] Boiling point: 35.degree. C./0.5 kPa (absolute pressure)
Example 11
Preparation of
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2
[0158] Into a three-necked flask made of glass, having an internal
capacity of 100 mL and equipped with a stirrer, a reflux condenser
and a dropping funnel, zinc (13 g, 200 mmol) was put, and 32 g of
dimethyl formamide was put. Then, the system was vacuumed to 27 kPa
(absolute pressure), and further, the internal temperature was
adjusted to from 65 to 70.degree. C.
CF.sub.2ClCFClCF(OCF.sub.3)CF.sub.2OCFClCF.sub.2Cl (12 g, 25 mmol)
obtained in Example 10 was slowly dropwise added thereto from the
dropping funnel, and during the reaction, the product was distilled
and quickly withdrawn. Thereafter, the crude product was
fractionated to obtain pure
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2 (4.0 g, yield:
47%).
[0159] .sup.19F-NMR (282.7 MHz, solvent: CDCl.sub.3, standard:
CFCl.sub.3) .delta. (ppm); -55.4 (F.sup.f, 3F) -86.5 (F.sup.h, 1F,
J.sub.hi=48 Hz), -87.0 to -88.6 (F.sup.d, 2F), -103.2 (F.sup.i, 1F,
J.sub.gi=116 Hz), -113.0 (F.sup.a, 1F, J.sub.ab=83 Hz), -121.3
(F.sup.b, 1F, J.sub.bc=111 Hz), -134.2 (F.sup.c, 1F, J.sub.ac=65
Hz), -134.4 (F.sup.e, 1F), -184.0 (F.sup.g, 1F, J.sub.gh=39 Hz).
Here, a to i of F.sup.a to F.sup.i correspond to the positions of
the fluorine atoms shown in the following formula: 4
[0160] IR: 1785 cm.sup.-1(CF.sub.2.dbd.CF--), 1838
cm.sup.-1(CF.sub.2.dbd.- CFO--).
[0161] Boiling point: 30.degree. C./25.3 kPa (absolute
pressure).
Example 12
Preparation of a Polymer by Polymerization of
CF.sub.2.dbd.CFCF(OCF.sub.3)- CF.sub.2OCF.dbd.CF.sub.2
[0162] CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2 (0.5 g)
obtained in Example 11 and perfluorobenzoyl peroxide (1.5 mg) were
put in a glass ampule, frozen in liquid nitrogen, vacuum deaerated
and then sealed. The ampule was heated in a warm water bath at
50.degree. C. for 220 hours, whereupon the solidified content was
taken out, and the remaining monomer was recovered under vacuum and
then dried at 200.degree. C. for 1 hour. The yield of the obtained
polymer (hereinafter referred to as the polymer A1) was 43%. A part
of the polymer A1 was dissolved in
perfluoro(2-butyltetrahydrofuran) (hereinafter referred to as
PBTHF), and the intrinsic viscosity was measured and found to be
0.268 dl/g. The molecular weight of the polymer was such that the
number average molecular weight (M.sub.n) was 102000, and the
weight average molecular weight (M.sub.w) was 201500.
[0163] The refractive index of the film of the polymer A.sub.1
prepared by press molding was 1.334, and T.sub.g was 113.degree. C.
The tensile characteristics of the polymer A1 were measured,
whereby the tensile modulus was 1325 MPa, the yield stress was 35
MPa, and the breaking elongation was 3.9%. Further, the zero share
viscosity at 230.degree. C. was measured by a rotary melt
viscosity-measuring apparatus and found to be 5500 Pa.multidot.s.
The glass transition temperature, as measured by a differential
scanning calorimetry (DSC), of a polymer obtained by polymerizing
monomer CF.sub.2.dbd.CFCF.sub.2CF.sub.2OCF.dbd.CF.sub.2
(hereinafter referred to as PBVE) under the same conditions, was
108.degree. C., whereby improvement of the glass transition
temperature of the polymer A1 was confirmed.
[0164] Further, the infrared absorption spectrum of the polymer was
measured, whereby absorption at 1785 cm.sup.-1 attributable to
CF.sub.2.dbd.CF-- and at 1838 cm.sup.-1 attributable to
CF.sub.2.dbd.CFO--, as observed with the monomer, was found to have
disappeared. This polymer A1 was found to have no pendant double
bond, be free from a crosslinking reaction, have a high conversion
and be completely soluble in R225 and thus found to be a cyclic
polymer. Further, from the .sup.19F-NMR analysis, it was confirmed
to be a polymer having repeating units of the following structure.
The polymer was found to be excellent in transparency and useful as
an optical resin material for e.g. an optical fiber or an optical
waveguide. 5
Example 13
Preparation of Polymer A2
[0165] CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2 (0.2 g)
and diisopropyl peroxy dicarbonate (5 mg) were put into a glass
ampule, frozen in liquid nitrogen, vacuum deaerated and then
sealed. The ampule was heated in a warm water bath at 40.degree. C.
for 20 hours, whereupon a solidified content was taken out and
dried at 200.degree. C. for 1 hour. The yield of the obtained
polymer (hereinafter referred to as the polymer A2) was 95%. A part
of the polymer A2 was dissolved in PBTHF, and the intrinsic
viscosity was measured and found to be 0.09 dl/g.
Example 14
Preparation of Polymer A3
[0166] Into an autoclave made of stainless steel and having an
internal capacity of 200 mL, water (80 g),
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF- .dbd.CF.sub.2 (15 g, 43.6
mmol) and perfluorobenzoyl peroxide (38 mg) were charged. The
autoclave was flushed with nitrogen and then heated until the
internal temperature of the autoclave became 70.degree. C.,
followed by polymerization for 20 hours. The obtained polymer was
washed with deionized water and methanol, and then dried at
200.degree. C. for 1 hour. The yield of the obtained polymer
(hereinafter referred to as the polymer A3) was 70%.
[0167] A part of the polymer A3 was dissolved in PBTHF, and the
intrinsic viscosity was measured and found to be 0.25 dl/g. The
refractive index of a film of the polymer A3 prepared by press
molding was 1.334, and T.sub.g was 113.degree. C. The tensile
characteristics of the polymer A3 were measured, whereby the
tensile modulus was 1330 MPa, the yield stress was 35 MPa, and the
breaking elongation was 3.5%. Further, the zero share viscosity at
230.degree. C. was measured by a rotary melt
viscoelasticity-measuring apparatus and found to be 5300
Pa.multidot.s.
Example 15
Preparation of Polymer B1 by Copolymerization of
CF.sub.2.dbd.CFCF(OCF.sub- .3)CF.sub.2OCF.dbd.CF.sub.2 with
Tetrafluoroethylene
[0168] Into a 200 mL autoclave made of stainless steel, R225 (80
mL), CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub.2 (5.6 g,
16.3 mmol) and perfluorobenzoic peroxide (25 mg) were charged.
While cooling the autoclave with liquid nitrogen, it was vacuumed
by a vacuum pump, and the vacuum pump was detached, and the
temperature was returned to room temperature, and then, again,
while cooling with liquid nitrogen, it was vacuumed by a vacuum
pump. This operation was repeated three times. Then, the internal
temperature of the autoclave was returned to room temperature,
whereupon tetrafluoroethylene (32 g, 320 mmol) was introduced. And,
heating was carried out until the internal temperature became
70.degree. C., followed by polymerization for 3 hours. Thereafter,
the remaining tetrafluoroethylene was purged, and the remaining
monomer was distilled off under reduced pressure, to obtain 29 g of
a white polymer (hereinafter referred to as the polymer B1). The
structure of the polymer B1 was analyzed, whereby it was found to
be a polymer having a structure derived from
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF.dbd.CF.sub- .2 introduced
in an amount of 1.4 mol % to a part of polytetrafluoroethylene.
[0169] T.sub.g of the polymer B1 was 130.degree. C.
Example 16
Preparation of Polymer B2 by Copolymerization of
CF.sub.2.dbd.CFCF(OCF.sub- .3)CF.sub.2OCF.dbd.CF.sub.2 with
PBVE
[0170] Into an autoclave made of stainless steel and having an
internal capacity of 200 mL, water (80 g),
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF- .dbd.CF.sub.2 (15 g), PBVE
(15 g), perfluorobenzoyl peroxide (75 mg) and methanol (1.5 g) were
charged. The autoclave was flushed with nitrogen and then heated
until the internal temperature of the autoclave became 70.degree.
C., followed by polymerization for 20 hours. The obtained polymer
(hereinafter referred to as the polymer B2) was washed with
deionized water and methanol and then dried at 200.degree. C. for 1
hour. The yield of the obtained polymer B2 was 80%.
[0171] A part of the polymer B2 was dissolved in PBTHF, and the
intrinsic viscosity was measured and found to be 0.33 dl/g. the
refractive index of a film of the polymer B2 prepared by press
molding was 1.338, and T.sub.g was 110.degree. C.
Example 17
Preparation of Polymer B3 by Copolymerization of
CF.sub.2.dbd.CFCF(OCF.sub- .3)CF.sub.2OCF.dbd.CF.sub.2 with
Perfluoro(2,2-Dimethyl-1,3-Dioxol) (Hereinafter Referred to as
PDD)
[0172] Into an autoclave made of stainless steel and having an
internal capacity of 200 mL, water (80 g),
CF.sub.2.dbd.CFCF(OCF.sub.3)CF.sub.2OCF- .dbd.CF.sub.2 (21 g), PDD
(9 g), diisopropyl peroxy dicarbonate (75 mg) and methanol (1.5 g)
were charged. The autoclave was flushed with nitrogen and then
heated until the internal temperature of the autoclave became
40.degree. C., followed by polymerization for 20 hours. The
obtained polymer (hereinafter referred to as the polymer B3) was
washed with deionized water and methanol and then dried at
200.degree. C. for 1 hour. The yield of the obtained polymer B3 was
90%.
[0173] A part of the polymer B3 was dissolved in PBTHF, and the
intrinsic viscosity was measured and found to be 0.36 dl/g. The
refractive index of a film of the polymer B3 prepared by press
molding, was 1.320, and T.sub.g was 158.degree. C.
Example 18
Preparation of Optical Fiber
[0174] The polymer A3 (93 parts) obtained in Example 14 and
perfluoro(triphenyltriazine) (7 parts) were put into a glass
ampule, and after sealing, uniformly melt-mixed at 240.degree. C.
to obtain a polymer mixture (hereinafter referred to as the mixture
C1). The refractive index of a film of the mixture C1 prepared by
press molding, was 1.354, and Tg was 93.degree. C.
[0175] Then, in accordance with the method disclosed in
JP-A-8-5848, an optical fiber was prepared by using the mixture C1
and the polymer A3. Namely, firstly, the mixture C1 was melted in a
sealed glass tube to obtain a columnar molded product (C1 a). Then,
the polymer A3 alone was melt-molded into a cylinder, and while
inserting the molded product (C1 a) into the hollow portion of this
cylinder, the temperature was raised to 240.degree. C. to join them
to obtain a preform. This preform was melt-spun at 240.degree. C.
to obtain an optical fiber wherein the refractive index gradually
decreases from the center portion towards the peripheral
portion.
[0176] The optical transmission loss of the obtained optical fiber
was measured by a cutback method, whereby it was 195 dB/km at 650
nm, 1.10 dB/km at 850 nm and 83 dB/km at 1300 nm, and it was an
optical fiber capable of transmitting light from a visible light to
a near infrared light excellently.
[0177] This optical fiber was heated and stored in an oven of
70.degree. C. for 1000 hours and then withdrawn, whereupon the
refractive index distribution was measured by an interface
interference microscope and compared with the refractive index
distribution before the heating and storing, whereby no change was
observed. Further, the transmission band was measured by a pulse
method to evaluate the transmission characteristics. The optical
fiber was heated and stored at 70.degree. C. for 1000 hours,
whereupon the transmission band was measured, whereby it was 350
MHz.multidot.km both before and after the heating and storing, and
no decrease of the band was observed, and thus it was confirmed
that the heat resistance was excellent.
Example 19
Preparation of an Optical Fiber
[0178] By means of an extruder, dichroic extrusion was carried out
so that a polymer of PBVE (intrinsic viscosity: 0.27 dl/g,
refractive index: 1.342) was disposed at the center and the polymer
A3 was disposed at the circumferential portion concentrically,
thereby to spin a core/clad optical fiber. The obtained optical
fiber had an outer diameter of 520 .mu.m and a core diameter of 485
.mu.m. Further, the optical transmission loss was measured by a
cutback method, whereby it was 148 dB/km at 650 nm, 88 dB/km at 850
nm and 73 dB/km at 1300 nm, and thus, it was an optical fiber
capable of transmitting light from a visible light to a near
infrared light excellently.
Example 20
Preparation of an Optical Fiber
[0179] A hollow tube made of the polymer B3 was put on the preform
obtained in Example 18, followed by melt spinning at 240.degree. C.
to obtain an optical fiber wherein the refractive index gradually
decreases from the center portion towards the peripheral portion.
The optical transmission loss of the obtained optical fiber was
measured by a cutback method, whereby it was 143 dB/km at 650 nm,
61 dB/km at 850 nm and 35 dB/km at 1300 nm, and it was confirmed to
be an optical fiber capable of transmitting light from a visible
light to a near infrared light excellently. Further, the increase
of the loss at a bending radius of 10 mm of this optical fiber was
measured at 850 nm and found to be 0.14 dB, and thus, it was found
to be an optical fiber having a small bending loss.
[0180] This optical fiber was heated and stored in an oven of
70.degree. C. for 1000 hours, whereupon the transmission loss was
measured, whereby no change was observed. Further, the transmission
band was measured by a pulse method to evaluate the transmission
characteristics. The transmission band was measured after heating
and storing the optical fiber at 70.degree. C. for 1000 hours,
whereby it was 275 MHz.multidot.km both before and after the
heating and storing, and no decrease of the band was observed, and
thus it was confirmed that the heat resistance was excellent.
Example 21
Preparation of Polymer D1
[0181] PDD and tetrafluoroethylene were subjected to radical
polymerization in a mass ratio of 80:20 by using PBTHF as a
solvent, to obtain a polymer which has T.sub.g of 160.degree. C.
and M.sub.n of 1.7.times.10.sup.5. This polymer was subjected to
heat treatment at 250.degree. C. for 5 hours in an atmosphere of a
fluorine/nitrogen mixed gas (fluorine gas concentration: 20 vol%),
to obtain a polymer (hereinafter referred to as the polymer
D.sub.1) having good light transmittance and thermal stability. The
polymer D1 was colorless transparent, and the refractive index was
1.305.
Example 22
Preparation of an Optical Fiber
[0182] By means of an extruder, dichroic extrusion was carried out
so that the polymer A3 was disposed at the center portion and the
polymer D1 was disposed at the circumferential portion
concentrically, to spin an optical fiber of core/clad type. The
obtained optical fiber had an outer diameter of 990 .mu.m and a
core diameter of 905 .mu.m. Further, the optical transmission loss
was measured by a cutback method, whereby it was 189 dB/km at 650
nm, 98 dB/km at 850 nm, and 75 dB/km at 1300 nm, and thus it was an
optical fiber capable of transmitting light from a visible light to
a near infrared light excellently.
Example 23
Preparation of an Optical Fiber
[0183] 92.5 parts of the polymer A3 and 7.5 parts of
perfluoro(1,3,5-triphenylbenzene) were put into a glass ampule,
sealed and uniformly melt-mixed at 250.degree. C. to obtain a
polymer mixture (hereinafter referred to as the mixture C2). The
refractive index of a film made of the mixture C2 prepared by press
molding, was 1.350, and T.sub.g was 95.degree. C.
[0184] Then, an optical fiber was prepared by using the mixture C2
and the polymer A3. Namely, firstly, the mixture C2 was melted in a
glass sealed tube to obtain a columnar molded product C2a. Then, a
cylinder was melt-molded solely by the polymer A3, and while
inserting the molded product C2a in the hollow portion of this
cylinder, heating was carried out at 220.degree. C. to join them to
obtain a preform. This preform was melt-spun at 240.degree. C. to
obtain an optical fiber wherein the refractive index gradually
decreases from the center portion towards the peripheral
portion.
[0185] The optical transmission loss of the obtained optical fiber
was measured by a cutback method. Whereby it was 185 dB/km at 650
nm, 96 dB/km at 850 nm, and 82 dB/km at 1300 nm, and thus, it was
an optical fiber capable of transmitting light from a visible light
to a near infrared light excellently.
[0186] This optical fiber was heated and stored in an oven of
70.degree. C. for 2000 hours, and then taken out, whereupon the
refractive index distribution was measured by an interface
interference microscope, and compared with the refractive index
distribution before the heating and storing, whereby no change was
observed. Further, the transmission characteristics were evaluated
by measuring the transmission band by a pulse method. The optical
fiber was heated and stored at 70.degree. C. for 2000 hours,
whereupon the transmission band was measured, whereby it was 335
MHz.multidot.km both before and after the heating and storing, and
no decrease of the band takes place, and it was confirmed that the
heat resistance was good.
Example 24
Preparation of an Optical Fiber
[0187] 90 parts of the polymer A3 and 10 parts of
chlorotrifluoroethylene oligomer were put into a glass ampule and,
after sealing, uniformly melt-mixed at 250.degree. C. to obtain a
polymer mixture (hereinafter referred to as the mixture C3). The
refractive index of a film of the mixture C3 prepared by press
molding was 1.345, and T.sub.g was 84.degree. C.
[0188] Then, an optical fiber was prepared by using the mixture C3
and the polymer A3. Namely, firstly, the mixture C3 was melted in a
sealed glass tube to obtain a columnar molded product C3a. Then,
the polymer A3 alone was melt-molded into a cylinder, and while
inserting the molded product C3a into the hollow portion of this
cylinder, heating at 220.degree. C. was carried out to join them to
obtain a preform. This preform was melt-spun at 240.degree. C. to
obtain an optical fiber wherein the refractive index gradually
decreases from the center portion towards the peripheral
portion.
[0189] The optical transmission loss of the obtained optical fiber
was measured by a cutback method, whereby it was 125 dB/km at 650
nm, 71 dB/km at 850 nm, and 53 dB/km at 1300 nm, and thus, it was
an optical fiber capable of transmitting light from a visible light
to a near infrared light excellently.
[0190] This optical fiber was heated and stored in an oven of
70.degree. C. for 1000 hours and then, withdrawn, whereupon the
refractive index distribution was measured by an interfaco
interference microscope and compared with the refractive index
distribution prior to the heating and storing, whereby no change
was observed. Further, the transmission characteristics were
evaluated by measuring the transmission band by a pulse method. The
transmission band was measured after heating and storing the
optical fiber at 70.degree. C. for 1000 hours, whereby it was 328
MHz.multidot.km both before and after the heating and storing, and
no decrease of the transmission band was observed, whereby it was
confirmed that the heat resistance was excellent.
INDUSTRIAL APPLICABILITY
[0191] According to the present invention, a novel fluoropolymer
which can be an optical resin material having a low refractive
index, excellent heat resistance and a high glass transition
temperature as compared with a conventional polymer of a
fluorinated diene having no side chain, and a novel fluorinated
diene compound having two unsaturated bonds, capable of presenting
such a fluoropolymer, can be provided. Further, by dissolving the
fluoropolymer in a certain specific fluorocarbon solvent, it is
possible to provide a useful fluoropolymer solution. Further, the
fluoropolymer has a low refractive index and excellent heat
resistance, whereby a high performance optical transmitter and a
plastic optical fiber can be provided.
[0192] The entire disclosure of Japanese Patent Application No.
2001-334352 filed on Oct. 31, 2001 including specification, claims
and summary is incorporated herein by reference in its
entirety.
* * * * *