JPS59179885A - Treating agent for carbon fiber raw yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a treatment agent for carbon fiber filaments (hereinafter referred to as precursor and thick), and more particularly to a precursor treatment agent containing polyoxyalkylene-modified aminopolysiloxane.

Conventionally, carbon fibers are produced by heating precursors (acrylonitrile polymer fibers, rayon, pitch yarn fibers, etc.) to various temperatures. In general, carbon fiber is a highly crystallized fiber with a very high carbon content and has extremely excellent heat resistance, chemical resistance, and corrosion resistance, and its uses are wide.

However, static electricity generated during the manufacturing process and fuzzing, thread breakage, etc. due to the physical force of the pond significantly deteriorate carbon fiber's properties such as strength and elasticity.

In order to compensate for this drawback, precursors are treated with various fiber treatment agents.

However, under the harsh conditions of carbon fiber production, the treatment agent often does not exhibit sufficient functionality. For example, Japanese Patent Publication No. 52-24186 discloses a processing agent made of aminosiloxane, which forms a film when heated, which accumulates as scum on drying rollers and the like.

This causes new fuzz, yarn breakage, etc., which prevents continuous operation and makes it impossible to sufficiently improve productivity.

In addition, it is difficult for conventional processing agents to adhere uniformly, resulting in insufficient densification of the precursor, leaving fine voids in the resulting carbon fibers, and cracking occurs around the voids when subjected to external force. However, it has drawbacks such as not being able to fully demonstrate its performance as a carbon fiber.

The present inventors have conducted extensive research into a precursor treatment agent that is resistant to high-end treatment, has uniform hJ adhesion, and can produce high-quality carbon fibers, and as a result, the present invention has been completed. is the formula [wherein R2, R4, and R5 are hydrogen or a lower alkyl or aryl group having 1 to 6 carbon atoms, R4 is 6 hydrogen or -R8 (in the group, -R6 and R7 are
~76 alkyl group, R8 is hydrogen or a lower alkyl group), A is an alkylene group having 1 to 10 carbon atoms, Q is a polyoxyalkylene group,
y, z is the molecular weight of siloxane from 1000 to 1000
A positive integer set to 00] Provided is a precursor treatment agent containing a polyoxyalkylene-modified aminopolysiloxane having the following as an active ingredient.

The polyoxyalkylene-modified aminopolysiloxane according to the invention is a copolymer having polyoxyalkylenesiloxyl residues and ami/siloxyl residues.

A liquid material having a molecular weight of about 1,000 to 100,000 or less is preferable. More preferably, it is within the range of about 1,000 to 30,000. In the formula, X, Y and 2 are positive integers that bring the molecular weight within the above range. The ratio of X and Y is preferably in the range of 1:I to 1:5.

In the above formula, the lower alkyl groups selected as R7 to R5 and R5 to R8 generally have 1 to 6 carbon atoms. Preferably it is an alkyl group having 1 to 4 carbon atoms. Q is preferably from po to 2000. It is a homopolymer or a copolymer of ethylene oxide, propylene oxide, butylene oxide, etc. Preferably ethylene glycol-/I/(
EO) is a copolymer of polypropylene (PO') and has an EO/POO ratio of 10.010 to 2.
It is 5/75.

Preferably, the polyoxyalkylene-modified aminopolysiloxane is incorporated in an amount of at least 0.01% (relative to the weight of the fiber) to the precursor. If the amount introduced is less than 0.01%, it is difficult to fully exhibit the effects of the present invention. Also,
Even if a large amount of polyoxyalkylene-modified aminopolysiloxane is introduced, no further effect can be expected and it is not a good idea. However, the two limits of the amount of polyoxyalkylene-modified aminopolysiloxane introduced are It is desirable that it be about 2%.

The polyoxyalkylene-modified aminopolysiloxane of the present invention is easily emulsified in water. Therefore, unlike aminosiloxane, emulsifiers or solvents are not required, and workability is improved.

Precursors used in the present invention include acrylonitrile polymer fibers, rayon fibers, pitch fibers, and polyvinyl alcohol fibers. The method of impregnating or containing a specific polyoxyalkylene-modified aminopolysiloxane in a precursor according to the present invention includes a method of adding the polyoxyalkylene-modified aminopolysiloxane to a spinning dope and then spinning, or a method of spinning the polyoxyalkylene-modified aminopolysiloxane, or It can be suitably produced according to each process, such as a method of impregnating and introducing polyoxyalkylene modification 7 minoborisiloxane into the fiber in a state where it has been prepared, or a method of attaching it to the densified fiber after spinning and drawing. can.

The precursor that has undergone the above treatment is made into carbon fiber by a conventional method. For example, 200 to 40 in oxidizing cloud air I
Flameproofing process heated to 0°C and carbonization process at 800 to 1500°C in N2 gas atmosphere IJFFC (in the case of graphitization process, a temperature of 2000°C or higher is adopted)
A firing method consisting of: If necessary, an antistatic agent, a sizing agent, or the like may be added to the processing agent of the present invention.

The polyoxyalkylene chains of the treatment agent of the present invention cause a dehydration reaction, prevent deterioration and decomposition of fibers, and adhere uniformly to the fiber surface. Therefore, the precursor becomes dense, the generation of voids is avoided, and the performance as a carbon fiber is sufficiently maintained.

In addition, the introduction of polyoxyalkylene chains makes the processing agent highly heat resistant and does not accumulate as scum on the roller. Therefore, continuous operation is possible and productivity is improved. At the same time, the polyoxyalkylene chain has an antistatic effect, suppressing the generation of static electricity, and further preventing fuzzing, spreading, etc.

Furthermore, the uniform adhesion of the treatment agent effectively suppresses exothermic reactions due to heat accumulation and prevents the fibers from sticking together with the soil.

The present invention will be explained in detail using a practical example. In the examples, % represents weight % unless otherwise specified.

Example (Psf'Eo crucible) A polyoxyalkylene-modified aminopolysiloxane represented by [formula, a+b=5000] was added to a 1000 filament precursor which had undergone a drying and densification process at a concentration of s o y/l. A precursor with 0.4% adhesion was obtained by applying a flame-retardant treatment to the obtained precursor in an air atmosphere at 200-300°C, and then applying N2 at 800-1200°C.
Carbonization was carried out in a gas atmosphere.

Table 1 shows the physical properties of the obtained precursor and carbon fiber.

Comparative Example 1 An aminosilogysan-based treatment agent was applied to the precursor described in Practical Wa Example 1 under the same conditions, and then carbonization was performed in the same manner as in Practical Wa Example 1.

Table 1 shows the physical properties of the obtained precursor and carbon fiber.

Table 1 (1) Strength measurement method A fired multifilament is impregnated with resin to make a test piece of a certain length, and the force of tensile cutting with a universal tensile tester is converted to unit area.

(2) Frictional strength measurement method Number of reciprocating movements until the yarn and alumina guide' are rubbed and cut (load: 100g, sample length: 15cm).

Actual Example 2 and Comparative Example 2 After immersing the precursor used in Actual Example 1 in the treatment liquids with the following formulations A to D and Comparative Example 2, precursors with the same adhesion amount as Actual Example 1 were obtained. Ta.

This precursor was carbonized in the same manner as Leprosy Example 1.

Table 2 shows the physical properties of the obtained carbon fiber.

Table 2

Claims (1)

[Claims] 1. Formula: [In the formula, R2, R3, R4 and R5 are hydrogen or lower alkyl having 1 to 6 carbon atoms) L/i or aryl group, R1 is water 6 7 alkyl group, R8 is a group having a hydrogen atom or lower alkyl group), A is an alkylene-spanning arylene group having 1 to 10 carbon atoms, and Q is a polyoxyalkylene group.
, Z is the molecular weight of polysiloxane from 1000 to 100
A positive integer equal to 000. ] A treatment agent for carbon fiber filament containing a polyoxyalkylene-modified aminopolysiloxane as an active ingredient. 2. Carbon fiber yarn/0.01 to 2% by weight of the fiber weight
The treatment agent according to item 1, which is attached. 3. The processing agent according to item 1, wherein Q is a copolymer of ethylene oxide and propylene oxide. 4. The processing agent according to item 1, wherein the polyoxyalkylene-modified aminopolysiloxane has a molecular weight within the range of 1,000 to 30,000.