JPS6225084B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a molded article of an acetylene high polymer, and more specifically, the present invention relates to a method for producing a molded article of an acetylene high polymer, and more specifically, a method for manufacturing a molded article of an acetylene high polymer, which comprises a cis content of 5 to 95% by weight of an acetylene high polymer having a cis content of 50% or more and an inert organic solvent.
A gel-like material consisting of 95 to 5% by weight is pressure-molded at a temperature of 50°C or less and a pressure of 10 to 1000 kg/cm ² , and then the resulting pressure-molded product is calendered at a temperature of 50°C or less to form a sheet. , relates to a method for manufacturing various molded products such as films.

The acetylene polymer obtained by polymerizing acetylene using a so-called Ziegler-Natsuta catalyst consisting of a transition metal compound and an organometallic compound is known as an organic semiconductor, but it does not melt even when heated.
Moreover, when heated in the presence of oxygen, it easily undergoes oxidative deterioration. Furthermore, no solvent has been found that can dissolve this acetylene high polymer, and the production of practical molded products of acetylene high polymers has heretofore been limited to the following two methods.

(a) A method of pressure molding a powdery acetylene high polymer; (b) A method of polymerizing a catalyst solution at the interface near the free surface of gaseous acetylene and a solid surface coated with the catalyst solution to form a film-like and A method for producing a fibrous acetylene polymer.

However, with the former method (a), only molded products with low mechanical strength can be obtained, and with the latter method (b), raw materials for films and fibers are limited, and in reality, thin films and fibrous molded products can be obtained. Not only was it difficult to obtain a molded product with a uniform thickness, but it was also difficult to obtain a molded product with a uniform thickness.

In view of this, the present inventors have discovered and already proposed a method for molding an acetylene polymer molded product having sufficient mechanical strength, a thick film thickness, and a uniform thickness.

However, in the method proposed above, a gel-like material with a very low bulk density is pressurized or roll-formed all at once, so advanced molding technology is required to obtain a molded product with a uniform film thickness. In some cases, the molded product was broken and became small pieces, making it impossible to obtain a molded product with a uniform film thickness. Furthermore, the mechanical strength of the molded articles obtained in this manner was not necessarily sufficiently satisfactory.

In view of the above points, the present inventors have arrived at the present invention as a result of various studies on methods for easily forming molded products with uniform film thickness. By the method of the present invention, it is not only possible to easily obtain a molded article with a uniform film thickness, but also the mechanical strength of the obtained molded article is high.

Examples of the method for producing a gel-like material of an acetylene polymer and an organic solvent using a catalyst in the presence of an organic solvent include the following method.

(1) μ−(η ¹ :η ⁵ −
cyclopcntadienyl)−tris(η−cyclo−
pentadienyl) dititanium (Ti−Ti) [(C ₅ H ₄ ) ₅
A method for producing a gel-like acetylene polymer by polymerizing acetylene using a special transition metal compound catalyst (C ₅ H ₅ ) ₃ Ti ₂ [SLHsu et.al.J.
chem.pys.69(1), 106-111 (1978)].

(2) (A) transition metal compound and (B) discovered by the present inventors
A method for producing a gel composition by polymerizing acetylene using a catalyst system consisting of an organometallic compound, an aromatic compound as a polymerization solvent, and a concentration of component (A) of 0.1 to 0.0001 mol/.

The gel of acetylene polymer and organic solvent used in the present invention is a state in which fibrous microcrystals (fibrils) of acetylene polymer are entangled and swollen in the organic solvent. The manufacturing method is not limited to the above method.

Examples of organic solvents used in the present invention include aliphatic or aromatic hydrocarbons, halogenated hydrocarbons, ethers, carboxylic acid esters, acid anhydrides, ketones,
Alicyclic compounds, oxygen-containing heterocyclic compounds, and the like can be used.

These organic solvents may be used as the polymerization solvent, or the polymerization solvent may be replaced with these organic solvents after the polymerization is completed.

Among these, aromatic hydrocarbons and aromatic ethers are preferred, and representative examples thereof include benzene, toluene, xylene, ethylbenzene,
Methyl phenyl ether (anisole), ethyl phenyl ether, diphenyl ether, n-dimethoxybenzene, p-dimethoxybenzene, n
-diethoxybenzene, p-diethoxybenzene, 1,3,5-trimethoxybenzene, and the like.

The organic solvent may be one or a mixed solvent of two or more of the above, or a part of the above organic solvent may be replaced with an aliphatic or aromatic alcohol or carboxylic acid.

After the polymerization of acetylene is completed, it is perfectly acceptable to remove a part of the polymerization solvent by a conventional method or to wash the acetylene polymer with an organic solvent to remove the catalyst, but it is not necessary to wash the acetylene polymer until pressurization. It is an essential condition of the present invention that the acetylene polymer be maintained in a gel state in the presence of an organic solvent, and if the acetylene polymer is dried before being pressurized, it will be difficult to mold it.

The amount of acetylene high polymer in the gel material used in the present invention is in the range of 5 to 95% by weight. If the acetylene high polymer content in the gel-like material is less than 5% by weight, it is difficult to produce a molded product with a uniform film thickness;
If it exceeds 95% by weight, the plasticity will be insufficient and pressure molding will become difficult.

The pressure range during pressure forming is 10 to 1000Kg/ ^cm2 , and if the pressure is less than 10Kg/ ^cm2 , cracking or cutting will occur during the next rolling process, while on the other hand, if the pressure is 1000Kg/ ^cm2
If it exceeds this, it becomes impossible to stretch during the next roll processing, making it impossible to obtain a molded product with sufficiently high mechanical strength. During pressing, most of the organic solvent is removed from the acetylene polymer, but a small amount of organic solvent remains. It is not preferable to remove the residual organic solvent at this stage because it will make the subsequent roll processing difficult.

Calender processing is a forming method using rolls that is widely used in the industry, and the gap and pressure of the rolls are determined by the required thickness of the resulting film-like acetylene polymer and the content of the gel-like material. Since it depends on the concentration of the acetylene high polymer, it cannot be absolutely limited.

2 gels of acetylene high polymer and organic solvent
It is possible to continuously produce acetylene polymer sheets or films with a uniform thickness by rolling them between rolls larger than a book, making it much more effective than conventional molded product production methods. Are better.

The acetylene high polymer that can be used in the present invention has a cis content of 50% or more; if the cis content is less than 50%, the flexibility of the acetylene high polymer decreases, resulting in a uniform molded product. I can't.

The cis content of the acetylene polymer can be controlled by the polymerization temperature and catalyst preparation conditions.

The pressure of the roll is 1Kg/cm2 ^or more, preferably 5
Kg/cm ² , and if the pressure is less than 1 Kg/cm ² , a molded product with sufficiently high mechanical strength cannot be obtained.

Although most of the residual organic solvent is removed from the acetylene polymer during calendering, a small amount of organic solvent may remain. Although there may be no practical problem with the remaining organic solvent as it is, it may be removed by a method such as vacuum drying.

By the above method, it is possible to obtain a molded product with strong mechanical strength and a uniform film thickness. The acetylene polymer molded product thus obtained has a very low electrical resistance and exhibits various electrical properties characteristic of so-called semiconductors.

The specific resistance at room temperature is 10 ⁸ for those with many cis structures.
It is about Ω・cm, but it decreases as the number of transformer structures increases, and for a transformer structure only, it is about 10 ⁴
~10 ³ Ω·cm, and also exhibits photoconductivity.
By utilizing the various electrical properties described above, this acetylene polymer can be used as an organic semiconductor material for manufacturing electrical equipment parts such as electrical resistance elements, heat-sensitive elements, and photo-sensitive elements.

The present invention will be explained in more detail with reference to Examples below.

Example 1 In a glass reactor 1 completely purged with nitrogen gas, 200 ml of toluene purified according to a conventional method was added as a polymerization solvent, and 2.94 mmol of tetrabutoxytitanium and triethylaluminum were added as catalysts.
The catalyst was prepared by charging 7.34 mmol in this order at room temperature. The catalyst was a homogeneous solvent. The reactor was cooled with liquid nitrogen, and the nitrogen gas in the system was exhausted using a vacuum pump. The reactor was cooled to -78°C and purified acetylene gas was blown at a pressure of 1 atmosphere.

The polymerization reaction was continued for 4 hours while maintaining the acetylene gas pressure at 1 atm. After polymerization, unreacted acetylene gas was removed and the system temperature was lowered to -78℃.
It was washed four times with 200 ml of purified toluene while maintaining the temperature. Even after washing, the solution turned slightly brown and the catalyst was not completely removed. The gel-like acetylene polymer swollen in toluene was in the form of a uniform film with entangled fibrils, and no powder or lump-like polymer was produced.

The above film-like gel material (acetylene high polymer content
37% by weight) was sandwiched between chloroplated ferro plates and press-molded while gradually increasing the pressure to 100 kg/cm ² while removing toluene to form a flexible and strong film with a thickness of 1.2 mm. I got the item. The amount of toene remaining in this molded article was 13% by weight.

This pressure-molded product was calendered at room temperature through two rolls (roll temperature is room temperature, roll gap 0.1 mm, roll diameter 3 inches, roll surface is chrome plating) to form a uniform film of acetylene high polymer with a thickness of 0.12 mm. Got a sheet. Approximately 1% by weight of toluene still remained in the film thus obtained, and the remaining toluene was removed by vacuum drying at room temperature.

The resulting acetylene polymer sheet has a cis content of 94% and an electrical conductivity (measured by the DC four-probe method).
It was a p-type semiconductor of 2.1×10 ^-7 Ω ^-1 ·cm ^-1 . In addition, the tensile strength of this acetylene high polymer (sample
JIS No. 2 1/2, tensile speed 5mm/min) is 1520Kg/
It was warm in ^cm2 .

Comparative Example 1 A film-like molded product obtained by vacuum drying the pressure-formed product obtained by press molding in Example 1 was subjected to a tensile test under the same conditions as in Example 1, and the tensile strength was 415 kg/ It was warm in ^cm2 .

Comparative Example 2 The gel-like acetylene high polymer obtained by polymerization in Example 1 was vacuum-dried at room temperature to remove a portion of the residual toluene, and the toluene content in the acetylene high polymer was reduced to 21% by weight. Then, calendering was performed using a roll in the same manner as in Example 1 to obtain a uniform acetylene polymer sheet having a thickness of 0.21 mm. When this molded product was dried in vacuum and subjected to a tensile test under the same conditions as in Example 1, its tensile strength was 747 kg/
It was warm in ^cm2 .

Example 2 The film-like gel obtained in Example 1 was vacuum-dried at room temperature to remove part of the toluene solvent and the acetylene high polymer content was 62% by weight. A sheet of acetylene polymer having a thickness of 0.14 mm was obtained by pressing and calendering in the same manner as in Example 1. After vacuum drying, a tensile test was performed and the tensile strength was 1770 Kg/cm ² .

Example 3 The toluene obtained by pressure molding in Example 1 was
Part of the toluene was removed by vacuum drying the molded product containing 5% by weight at room temperature, resulting in a residual toluene content of 5% by weight.
A uniform acetylene polymer sheet having a thickness of 0.11 mm was obtained by calendering in exactly the same manner as in Example 1, except for the following. After drying this sheet under vacuum at room temperature, a tensile test was conducted and the tensile strength was 1650.
It was Kg/ ^cm2 .

Claims (1)

[Claims] 1 Acetylene polymer with a cis content of 50% or more 5
A gel-like material consisting of ~95% by weight and 95~5% by weight of an inert organic solvent is heated at a temperature of 50°C or less and a pressure of 10~1000kg/
1. A method for producing an acetylene polymer molded article, which comprises pressure molding in a range of cm ² and then calendering the obtained pressure molded article at a temperature of 50°C or less.