JPH0228602B2 - HORIASECHIRENNOSEIZOHO - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a new method for producing polyacetylene, and relates to a method for mass producing high-quality polyacetylene, which is in high demand as a conductive material. . Polyacetylene obtained by the production method of the present invention is widely used for battery materials, electrical parts, and other uses.

[Conventional technology]

Various methods for synthesizing polyacetylene have been proposed in the past, and one of the known methods is the Shirakawa method (J.Polym.Sci., Polym.Chem.Ed., 12 , 11, 1974).
), Ruchinger method (J.Org.Chem., 27 , 1591,
1962), Electrolytic Polymerization Method (Nippon Publication., 1982-
206612), Solution Polymerization Method (Nippon Publication., 1982-
174340, 174351, 1974, 74706), orientation polymerization method (Nippon Publications, 1982-33309), solid phase interfacial polymerization method (Nippon Publications, 1984-108408, 1982-120715), Wax interfacial polymerization method (Nippon Special Publication., 1982-162618)
and polyvinyl chloride dehydrochlorination method (Annual Conference of the Society of Polymer Science, Proceedings, 32 , No. 3540, 1983).

[Problem that the invention seeks to solve]

The inventors conducted numerous follow-up experiments on each of these methods, and found that the Shirakawa method is superior as a method for producing polyacetylene films, while the oriented polymerization method has various difficulties in industrial implementation. However, the solid phase interfacial polymerization method and the wax interfacial polymerization method imposed certain restrictions on the growth of polyacetylene molecules, making it impossible to obtain a film as strong as that produced by the Shirakawa method. Here, the present inventors investigated a method for manufacturing polyacetylene film or polyacetylene ribbon in a batch or continuous manner using the free surface of a special liquid, and as a result, they finally completed the present invention. . The polyacetylene film obtained through the method of the present invention is of excellent quality and easy to clean, but it is difficult to remove residual ash from an organic metal melting medium such as the Shirakawa method and to peel it off from a glass wall. This succeeded in greatly reducing the burden of complicated operations.

[Means for Solving the Problems] and [Operation] That is, the present inventors left a mixture of an organosilicon compound solvent or a mixed solvent of this and a hydrocarbon with a polymerization catalyst added thereto, or They discovered that very homogeneous polyacetylene can be obtained in good yield when the free surface is brought into contact with acetylene gas under reduced pressure and the reaction is carried out at -80°C to 0°C while moving in a fluid state.

As organosilicon compound solvents, products belonging to silicone oils and silicic acid esters are commercially available. Silicones, which mainly have a polymethylsiloxane structure, exhibit water repellency similar to that of paraffin, and the viscosity of their liquids changes little with temperature. There are several types of silicone oil, and the silicone oil suitable for the present invention is called silicone oil and is used as a mold release agent, antifoaming agent, lubricating oil, anti-vibration oil, water repellent, hydraulic oil, insulating oil, cosmetic oil, etc. Selected from among the varieties used.

As the silicic acid ester, tetraethyl silicate, tetramethyl silicate, tetrapropyl silicate, tetrabutyl silicate, a liquid product obtained by dealcoholization and partially oligomerization of these, or a liquid product obtained by reacting these with glycol or the like is used. Commercially available organosilicon compound solvents that are easy to handle and industrially available include Shin-Etsu Chemical's KF96, KF96L, KF96H,
KF50, KF54, Toshiba Silicone TSW, TSK
Oily substances classified as Toray Silicone
SH61, SH200, SH225, SH510, SH550,
SH556, SH560, SH710, SH1265, SH3530,
SH3531, SH3771, SH3749, SH6702, SH6703
etc.

These solvents can be used alone or as a mixture of two or more, or in a mixture with a hydrocarbon. Hydrocarbons used here include propane, butane, pentane, hexane, heptane, octane, petroleum ether, gasoline, ligroin, petroleum benzine, petroleum naphtha, volatile oil, kerosene, light oil, liquid paraffin, benzene, toluene, xylene, and alkylbenzene. , dialkylbenzene, cracked gasoline, BTX fraction, naphthalene oil, methylnaphthalene, etc., either singly or as a mixture of two or more thereof can be used in combination with the above-mentioned organosilicon compound solvent. However, the amount of organosilicon compound in the mixed solvent is 50% by weight or more. Regarding the reason why the above-mentioned organosilicon compound solvent or a mixed solvent of this and a hydrocarbon can be used as a solvent for the polymerization of the present invention,
Although it is difficult to provide a complete theoretical explanation, it can be considered as follows. The polymerization catalyst does not react with the above solvent, but simply dissolves or disperses, and easily collects on the free surface during the reaction with acetylene; The polymer does not sink into the above solvent; The polymer is easily separated from the solvent. Things that can be done: The catalyst component and the solvent can be easily removed from the polymer by operations such as washing; The solvent can be easily recovered and can be applied industrially. The present inventors confirmed this advantage through many experiments and completed the present invention.The quality of polyacetylene obtained by the production method of the present invention is higher than that of the conventional method. It has become clear that it is superior.

The polymerization catalyst used in the present invention is a binary catalyst, which is a combination of trialkylaluminum and a transition metal compound. Examples of the transition metal include titanium, zirconium, vanadium, cerium, neodymium, niobium, and tantalum. The chemical formulas of typical catalyst components are as follows. That is, Ti
(OR) ₄ +AlR ₃ , Zr (OR) ₄ + AlR ₃ , Nd (OCOR) ₃
+AlR ₃ , Nd(OR) ₃ +AlR ₃ , NbX ₅ +AlR ₃ ,
TaX ₅ +AlR ₃ etc., where R represents an alkyl group and X represents a halogen atom. Such a catalyst may be prepared in advance and added to the mixture, or may be added separately to the mixture.

In the method of the present invention, acetylene gas is brought into contact with the free surface of a mixed solution containing such a catalyst, and what is important here is the pressure and temperature of the reaction system. In order to proceed with the polymerization reaction as mildly as possible, the acetylene gas is brought into contact with the polymer at a reduced pressure below atmospheric pressure. Maintaining the reaction system at a reduced pressure also has the effect of lowering the temperature of the free surface of the mixture where the polymerization reaction proceeds, reducing the light gas generated by the aging of the binary polymerization catalyst itself. It also has the effect of removing from the free surface, but it goes without saying that the pressure should not be reduced to such a degree that the mixed solution foams or bumps during the reaction. Acetylene gas may be charged as is or diluted with an inert gas, but in any case the pressure of the reaction system should be maintained at 10-700 mmHg, particularly preferably 50-500 mmHg. It is well known that the reaction is carried out at a partial pressure of acetylene gas of 500 to 600 mmHg, but in the present invention, it is necessary to maintain the reaction system under considerably reduced pressure even if an inert gas is mixed in. , this point is unknown.

When the reaction rate is carried out on the free surface of the liquid mixture of the present invention, the reaction rate is considerably suppressed compared to the case of the Shirakawa method or the like. The reaction of the present invention should be carried out at -80°C to 0°C, particularly preferably at -70°C to -20°C, in order to form a normal molecular chain of polyacetylene. If the reaction temperature exceeds 0°C, branches will occur in the polyacetylene molecules, reducing the conductivity and mechanical properties.
It is desirable to carry out the slow polymerization under reduced pressure.
Although the polyacetylene obtained by the production method of the present invention as described above can be easily separated from the mixed liquid,
In order to guarantee the quality and separation effect of polyacetylene, it is necessary to let the mixed liquid stand still or move the mixture in a laminar flow while bringing the acetylene gas into contact with the free surface, and this free surface must be prevented from being mechanically disturbed. You should be careful. This is because the reaction is slow under the conditions of the production method of the present invention, and the disturbance causes unnecessary distortion in the properties of the polymer. The operation of keeping the free surface as still as possible is most easily carried out batchwise, and the operation of moving the mixture in a laminar manner can also be carried out continuously using a device that gently flows or circulates the mixture. It can be done.

〔Example〕

Example 1 SH-510 silicone oil manufactured by Toray Silicone
A mixture of 75 ml of triethylaluminum, 13 ml of triethylaluminum, and 7.5 ml of tetrabutoxytitanium was placed in a flat-bottomed flask, cooled to -50°C, volatile substances were removed under reduced pressure, the free surface of the liquid was allowed to stand, and acetylene gas was added to it. contact. The flow rate of acetylene gas is 20/
Continue the reaction for about 1 hour at hr. At this time, the pressure of the reaction system was maintained at 500 to 550 mmHg, and the reaction temperature was −40 mmHg.
Maintained at ~-50℃. After the reaction is complete, blackish brown polyacetylene is formed in the form of a film on the free surface.
This is taken out and thoroughly washed by immersing it in cold toluene. Next, 50% of this polyacetylene film
It is washed with a hydrogen borofluoride-acetic acid solution, stabilized, washed again with a toluene-methanol mixture, and then dried. The polyacetylene film obtained here is relatively flexible, has a thickness of 60 microns, has an electrical conductivity of about σ=10 ^(-)3 S/cm, and is relatively stable in air.

Example 2 SH-550 silicone oil manufactured by Toray Silicone
A mixture of 1500 ml, xylene 300 ml, triethylaluminum 250 ml, tetrabutoxytitanium 100 ml, and neodymium trifluoroacetate 50 g is placed in a dropping funnel, and it flows gently from the bottom onto the glass plate to spread the free surface and move the liquid as a laminar flow. . Acetylene gas is brought into contact with the moving surface of this laminar flow material. In this case, the reaction temperature is maintained at -25 to -20°C and the pressure of the reaction system is maintained between 200 and 400 mmHg. The amount of acetylene gas charged into the system was 100/hr, and the reaction continued for 4 hours. After the reaction is completed, unreacted acetylene gas is removed, and toluene is actively poured down from the dropping funnel to wash the polyacetylene surface.
The polyacetylene produced is then collected, filtered, and washed with a 1% iodomethanol solution. Then, it is washed again with toluene, dried, and crushed to obtain polyacetylene powder. The yield of polyacetylene powder was 24% based on the acetylene used. This polyacetylene powder is doped with iodine and has excellent properties as a conductive filler.

〔Effect of the invention〕

As described above, the present invention is useful as a method for obtaining high-quality polyacetylene with high utility value in an easily purified state.

The polyacetylene film or polyacetylene powder produced by the production method of the present invention is suitable for plastic battery electrodes, solar cell electrodes, conductive fillers, and other electrical applications, and various products produced using this polyacetylene are industrially applicable. It has a very high utility value as a daily necessity.

Claims (1)

[Claims] 1. A mixed solution prepared by adding a polymerization catalyst to an organosilicon compound solvent or a mixed solvent of this and a hydrocarbon is allowed to stand still or is moved in a laminar flow, and its free surface is brought into contact with acetylene gas under reduced pressure at -80℃~ A method for producing polyacetylene, characterized by carrying out the reaction at 0°C.