JPS61208A - Production of fluorine-containing polymer - Google Patents

Abstract

PURPOSE:To obtain the titled polymer excellent in water- and oil-repellency, chemical resistance, heat resistance, weather resistance, etc., by polymerizing a specified, fluorine-containing unsaturated ester monomer in the presence of an organo-aluminum catalyst. CONSTITUTION:The titled polymer is obtained by polymerizing a fluorine-containing unsaturated ester monomer of formula I [wherein R1 is CnH2n+1 (wherein n is 0-5), and R2 is formula II (wherein Rf is a 1-20C polyfluoroalkyl, and R<1> is a lower alkyl or Rf)] which has been purified by distillation in a N2 or He stream, deoxygenated completely and dehydrated with a molecular sieve and having a purity >=99.5% at -78-100 deg.C in the presence of 0.01-10mol%, based on said monomer, organoaluminum catalyst of formula III (wherein m is 1-3 and X is H, Cl, Br, or I) in an organic solvent of an aromatic or aliphatic hydrocarbon, stopping the polymerization by the addition of a protonic organic solvent (e.g., methanol), repeatedly washing and filtering the product and drying it.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the production of a fluorine-containing polymer, which is characterized by polymerizing a fluorine-containing unsaturated ester monomer such as a fluorine-containing acrylate or a fluorine-containing methacrylate in the presence of an organic aluminum solvent. be.

(Industrial Application Field) Fluorine-containing acrylates or fluorine-containing methacrylates provide industrially important polymers. In particular, fields where the functionality of fluorine-based compounds can be utilized include textile treatment agents that take advantage of the water and oil repellency of fluorine-based products, fluorine-based rubbers and plastics that take advantage of their chemical and heat resistance, and film materials that take advantage of their weather resistance. Applications to paints, optical materials such as optical fibers that take advantage of their low refractive properties, resist materials, and medical materials have been studied and many have been put into practical use.

(Prior Art) The polymerization method of the monomers currently in practical use is radical polymerization. Solution polymerization in organic media using, for example, oil-soluble peroxides such as benzoyl peroxide, azo compounds such as azobisisobutyronitrile, ammonium persulfate, inorganic peroxides such as hydrogen peroxide, etc. This is a method of carrying out suspension polymerization or emulsion polymerization in an aqueous system.

(Problems to be Solved by the Invention) On the other hand, hydrocarbon-based acrylates or methacrylates, such as methyl acrylate and methyl methacrylate, similarly undergo radical polymerization, but n-
It is known to produce isotactic polymers through cyanionic polymerization using organometallic catalysts such as butyllithium. Such anionic polymerization reactivity is well known for hydrocarbon monomers, and there is a famous reactivity diagram for export. (For example, T, 'Tsuruta.

”Progress in Polymer 5cie
nce, Japan” 51 (1972) Koaans
ha) According to this, the above-mentioned acrylates and methacrylates are dangerous to polymerize using an organoaluminum catalyst alone. However, α
, α1-dipyridyl, and triphenylphosphine, anionic polymerization is initiated even in a nonpolar solvent such as toluene, and a polymer is obtained. (For example, M,
ecla.

T, Hlrano, T, Tsurutay Mac
romol, Ohem, 150127 (King 971)
) In this way, even organoaluminum catalysts can be used in a solvated form (
The catalyst (8o1vent 5eparated) has the ability to initiate anionic polymerization.

Based on the above facts, we investigated the reactivity of organoaluminum catalysts with various fluorine-containing acrylates and fluorine-containing methacrylates, and found that certain fluorine-containing unsaturated esters are highly polymerizable to form polymers. I discovered that.

(Means for solving the problems) Fluorinated unsaturated ester used in the present invention. . . R
.

[However, in the formula, RI=CnH2n+1. n is an integer between θ and 5.

polyfluoroalkyl group. R1 is a lower alkyl group or an Rf group. ], specifically hexafluoroisoglobyl acrylate, hexafluoroinpropyl methacrylate, 3,3.3-)lifluoroinpropyl acrylate, 3,3. ! l-) Lifluoroisopropyl methacrylate and the like.

The organoaluminum compound that is a polymerization catalyst has the general formula (R1
)rn(X), mm1 [However, Rt=OnH2n+.

n is an integer from 1 to 5. or hydrogen, chlorine, bromine, iodine], specifically triethylaluminum, diethylaluminum chloride, ethylaluminum dichloride, diethylaluminium hydride,
Diethylaluminum iodide, trimethylaluminum dimethylaluminum chloride, methylaluminum dichloride, tri-n-propylalkinium, syn-n-7' lobylaluminum chloride, tri-n-butylaluminum, di-n-butylaluminum chloride, triisobutylaluminum, Examples include diisobutylaluminum hydride, diimbutylaluminum chloride, and isobutylaluminum dichloride.

These aluminum compounds are usually n-hexane,
Used as a dilute solution in n-hebutane, benzene, toluene, etc.

The manufacturing method of the present invention will be described in detail below.

The fluorine-containing unsaturated esters are purified by distillation under a stream of nitrogen or helium, and those having a purity of 99.5% or higher and completely deoxidized are used. Since water inhibits polymerization, it is preferable to dehydrate using molecular sieves or the like.

Commercially available organic aluminum compounds are used, but
Commercially available products are used as they are or after being distilled under reduced pressure under a stream of nitrogen or helium.
It is used as a hydrocarbon solution of 1 to 58 nol.

The amount of the organoaluminum compound added to the polymerization system is 10 to 0.01 mole, preferably 2 to 0.05 mole, based on the fluorine-containing unsaturated ester. As the polymerization solvent, inert aprotic organic solvents such as n-hexane, n-heptane, benzene, toluene, xylene, etc. are used, but aromatic hydrocarbons or aliphatic Group hydrocarbons are preferred;
Polymerization does not proceed in polar solvents such as ethyl ether and dihydrofuran.

The first reaction is carried out in a glass ampoule or in a reactor equipped with a stirrer, but it is necessary to dry the inside of the vessel and replace it with nitrogen before charging the raw materials.

The polymerization temperature is -78°C to 100°C, preferably -20°C to
80°C is suitable. The polymerization time is not limited and is determined by the type of fluorine-containing unsaturated ester and organoaluminum or a combination thereof.

In order to terminate the polymerization, a small amount of a protic organic solvent such as methanol or ethanol is added to the polymerization system. The generated polymer is washed with methanol-hydrochloric acid, etc., and then
Wash with an organic solvent such as methanol, filter, and dry.

(Function) The above-mentioned fluorine-containing unsaturated esters may be used alone or in copolymerization of two or more, and may also be used with hydrocarbon-based vinyl ketos, acrylontolyl, etc. that are polymerized with organic aluminum. Can be copolymerized. On the other hand, organoaluminum catalysts can also be used as Ziegler-Natsuta catalysts, either alone or in combination of two or more, optionally with the addition of a titanium compound or the like.

Examples of uses of the fluorine-containing polymer according to the present invention include water and oil repellents, resist materials, materials for optical fibers, molding materials such as sheets and films, paints, adhesives, and medical materials.

Hereinafter, the present invention will be specifically explained using Examples.

Example 1 A glass reaction tube with a capacity of 50 d was dried and replaced with nitrogen, and 20 d of purified toluene, 20 m%k of hexafluorotetraisopropyl methacrylate, and 0.4 mmol of ethylaluminum were charged in this order under a nitrogen stream. -20℃
Polymerization was carried out for 7 days to obtain a polymer with a yield of 33%. Intrinsic viscosity of polymer measured in acetone solution at 30℃
η] was 0.206.

Example 2 Polymerization was carried out at 0° C. for 7 days in the same manner as in Example 1. The yield of the polymer was 50%, and the intrinsic viscosity was 0.053.

Example 5 Polymerization was carried out at 25° C. for 7 days in the same manner as in Example 1.

The yield of the polymer was 90%, and the intrinsic viscosity was 0.027.

Example 4 Polymerization was carried out at 40° C. for 7 days in the same manner as in Example 1. The yield of the polymer was 97%, and the intrinsic viscosity was 0.010.

Example 5 Polymerization was carried out at 60° C. for 7 days in the same manner as in Example 1.

The yield of the polymer was 85%, and the intrinsic viscosity was 0.018.

Example 6 A glass reaction tube with a capacity of 50 y was dried and replaced with nitrogen, and 20 mmol of toluene purified under a nitrogen stream, 20 mmol of hexafluoroisoglobyl methacrylate, and 0.41 mol of diethylaluminum chloride were charged in order, and the sealed tube edge 401: Polymerization was carried out for 7 days at : to obtain a polymer with a yield of 95%.The intrinsic viscosity (V) of the polymer measured in an ascent solution at 30°C was 0.013.

Example 7 A glass reaction tube with a capacity of 50 m/m was dried and replaced with nitrogen,
20 rnl of toluene purified under nitrogen stream.

Hexafluoroinpropyl acrylic V-) 20 mmol,
0.4 mmol of triethylaluminum was charged in sequence, and after the tube was sealed, polymerization was carried out at -20'C for 7 days to obtain a polymer with a yield of 31%. The intrinsic viscosity [η] of the polymer measured in an acetone solution at 30° C. was 0.185.

The thermal decomposition initiation temperature of the polymers produced in Examples 1 to 6 was 320° C. or higher, and the glass transition point exhibited a characteristic absorption.

Comparative Example 1) Tetrahydride was used as a solvent instead of toluene in Examples 1 to 5,
Polymerization was carried out, but no polymer was produced.

Comparative Example 2 Polymerization was carried out using methyl methacrylate in place of hexafluoroisoglobil methacrylate in Examples 1 to 5, but no polymer was produced.

Comparative Example 3 Polymerization was performed using 2,2,2-trifluoroethyl methacrylate instead of hexafluoroinpropyl methacrylate in Examples 1 to 5, but the yield of the polymer was 0 to 1.
It was 4%.

Claims (1)

[Claims] 1) General formula▲There are mathematical formulas, chemical formulas, tables, etc.▼ [However, in the formula, R_1=CnH_2_n_+_1, n is 0
An integer between ~5. ▲There are mathematical formulas, chemical formulas, tables, etc. ▼ is a polyfluoroalkyl group having 1 to 20 carbon atoms. R^1 is a lower alkyl group or an R_f group. ] A method for producing a fluoropolymer, which comprises polymerizing a fluorine-containing unsaturated ester monomer represented by the following in the presence of an organoaluminum catalyst. 2) General formula (R1)_m(X)_3_-_mAl [However, R_1=CnH_2_n_+_1, n is 1 to 5
an integer of m is an integer from 1 to 3. X is hydrogen, chlorine, bromine or iodine. ] The method according to claim 1, characterized in that an organoaluminum catalyst represented by these is used. 3) The method according to claims 1 and 2, characterized in that an aromatic hydrocarbon compound or an aliphatic hydrocarbon compound is used as the polymerization solvent.