JPS63196770A - Carbonaceous fiber having organic part - 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] (Industrial application field) The present invention relates to carbonaceous fibers containing organic parts.

More particularly, the present invention relates to ultra-fine vapor-grown carbonaceous fibers containing organic parts by adding organic polymerizable monomers.

(Prior Art) Carbon fiber is used as a covering material for each ram due to its excellent mechanical properties, and its demand has been rapidly increasing in recent years. However, conventional carbon fibers are manufactured through complicated processes such as firing and carbonizing organic fibers, and are limited in terms of cost. In contrast, a method has been attempted in which hydrocarbons are thermally decomposed and carbon fibers are produced on a substrate through a gas phase reaction.

Furthermore, the present inventors introduced hydrocarbons into a heating space together with a specific organic metal compound and a carrier gas, and in the space rather than on the substrate, - in the floating state of the glaze, extremely fine and We succeeded in synthesizing carbonaceous fibers with a unique structure. This method is a simple and industrially valuable method.

(Problems to be solved by the invention) The carbonaceous fibers obtained here have a unique structure, are crystalline,
It has excellent orientation, and therefore has excellent mechanical properties, electrical properties, and suitability for electrode materials, and is expected to be put into practical use. However, because of this structural perfection, it has poor adhesion and wettability with other materials such as resins and solvents, which limits its use.

(Means for Solving the Problems) The present inventors have investigated various methods for modifying the surface of the above-mentioned carbonaceous fibers. Due to the ultra-fine and fine fibers that come from carbon fibers, we have considered the reaction method, selection of conditions, reaction control measures, reaction treatment equipment, and the form of carbon'R woven fibers during reaction treatment. Ta. As a result, the present invention was achieved by successfully retaining the organic portion without damaging the fiber body.

That is, in the present invention, the organic part is added to the carbonaceous fiber 11 by adding an organic polymerizable monomer.
It is a carbonaceous fiber having o* and a diameter of O-01 to 4 μm.

In the present invention, the carbonaceous fiber has a diameter of 0.01 to 4μ.
m, preferably 0.05 to 0.01 to 2 μm%
It is 1 μm. The length of the fibers is not particularly limited, but when used as a reinforcing material, the longer the better, and the ratio of fiber length (L)/fiber diameter (D) is preferably 10 or more, particularly 50 or more.

The carbonaceous fiber of the present invention is a fiber formed by a vapor growth method and has a unique shape consisting of a core and a carbon layer surrounding it that looks like an annual ring when observed with an electron microscope. , the carbon layer has the property of being easily converted into graphite or graphite. That is, the carbonaceous fiber as used in the present invention is a general term for carbonaceous fibers such as carbon fibers formed by a vapor phase growth method and fibers similar to graphite obtained by heat-treating the carbon fibers.

In the present invention, various compounds having an unsaturated group are used as the organic polymerizable monomer. For example, preferred monomers include styrene, vinyl chloride, vinylidene chloride, vinylidene fluoride, vinyl acetate, and acrylonitrile. ,
These include butadiene, imprene, chloroprene, cyclopentadiene, vinylgiridine, methacrylic esters, methacrylamides, acrylic esters, acrylic amides, fumaric esters, maleic esters, and the like. The monomer to be used is selected depending on the use of the carbonaceous fiber. For example, when used in a composite material with a resin, the added organic part has high wettability and adhesiveness with the resin. One method is to select one based on structural similarity, one estimated from solubility parameters, or one whose thermal stability is determined from thermal decomposition temperature. Particularly preferred monomers include, for example, when reinforcing polyamide resins, epoxy resins, polyether resins, etc., it is preferable to use acrylamide, methacrylamide, etc. in part or in whole. It is also effective to use monomers in combination.

For example, when reinforcing rubber or olefin resin,
In addition to diene monomers and amide thread monomers, styrene monomers and olefin monomers can also be preferably used.

Examples of methods for adding these organic polymerizable monomers to carbonaceous fibers include plasma treatment of carbonaceous fibers in the presence or absence of organic polymerizable monomers, electron beam treatment, xIIiIγ Examples include a method of performing excitation treatment such as irradiation with radiation such as rays, irradiation with ultraviolet rays or radar light, and then, after praying for these treatments, contact reaction with an organic polymerizable monomer. . In particular, among the above excitation treatment methods, plasma treatment methods and electron beam irradiation methods are highly effective and are preferred.

Among these, to give an example of plasma processing methods, it is convenient to mainly use inorganic gas as a carrier and use plasma generated by low frequency discharge, high frequency discharge, microwave discharge, DC glow discharge, corona discharge, etc. This is done by exposing carbonaceous fibers to this plasma state.

Here, examples of the inorganic gas include Ar and He.

N2. H2+ o2. Various gases such as NH3e, CO+co2, etc. can be used, and a mixed gas of straw gas can also be used. Preferred gases include Ar, N2*02e
Ar to NH3+%.

The gas is N2p011+ or a mixture thereof.

The pressure of the gas when generating plasma is o, ooi
Torr to 1 atm, especially 0.1 to 100 Torr.The plasma treatment time varies depending on the type of gas, the capacity of the plasma generation power source, the shape and form of the carbon fiber to be treated, but generally 0.01 seconds to 20 minutes,
Preferably, the time is 0.1 seconds to 10 minutes, particularly 0.5 seconds to 5 minutes; shorter times than this will produce the effect of reactivity with the organic polymerizable monomer. On the other hand, longer than this range In this case, undesirable conditions such as noticeable surface etching of the carbonaceous fibers occur.

After such an excitation treatment method such as plasma treatment or electron beam irradiation, the organic polymerizable monomer can be catalytically reacted with the organic polymerizable monomer in a gaseous, liquid, solution, or emulsion state. They are brought into contact and reacted in various states. The conditions for reacting the organic polymerizable monomer include a temperature range of 09C to 600C, preferably room temperature to 200C, and a reaction time of about 1 second to 2 hours, preferably several seconds to 1 hour. Additionally, during the reaction, it is also preferably used to remove oxygen from the reaction system. Under these conditions, organic polymerizable monomers are added to carbonaceous fibers, and generally,
The amount to be added is 0.01 to 100 to 100, preferably 0.1 to 50, per gram of carbonaceous fiber, and the amount to be added is adjusted depending on the purpose.

In the present invention, as a method for measuring the amount of the organic part added, the weight of the raw material carbonaceous fiber before addition is weighed in advance, and the excitation treatment and addition reaction of the organic polymerizable monomer are performed. After that, it is washed and dried, weighed again, and the difference can be converted into weight per gram of raw carbon fiber. In addition, using a thermobalance, inert gas (Alin, He, N
As an auxiliary method, it is also possible to decompose the organic part of the carbonaceous fiber to which the organic part has been added under (2), and estimate the amount of the organic part from the amount of weight loss.

After being added in this way and after death, it can be used for practical purposes by washing and drying as necessary, or by attaching sizing materials and surface treatment auxiliary materials. For example, when used for composite reinforcement with resin, rubber, etc., epoxy resins, phenol resins, unsaturated ester resins, amide resins, silicone resins, rubber latex, or mixtures thereof can be preferably used.

(Example) The present invention will be explained below using examples.

Example 1 Vapor grown carbon fibers with a diameter of 0.1 to 0.8 μm (trisacetylacetonate iron and benzene were introduced into a heating space at 1400°C and synthesized in a floating state) were compressed using a press.
This was installed in a high-frequency plasma (13.56 MHz) device, and after exhausting to 1Q-' Torr, the pressure was adjusted to 0.1 Torr by flushing with argon.

A high frequency power source was oscillated with an output of 200 W to generate plasma, and plasma treatment was performed for 3 minutes. After stopping the plasma, the carbon fibers subjected to 7' plasma treatment were immersed in an aqueous solution of 15% by weight of acrylamide and 5% by weight of hydroxyethyl acrylate, reacted at 80°C for 60 minutes, washed and dried to obtain the The amount of organic part added to the carbonaceous fiber was measured and found to be 15 rlQ/g. This fiber wets well when immersed in water. Furthermore, when mixed with epoxy resin and molded, a remarkable reinforcing effect was observed, for example, an improvement in bending strength was observed.

Comparative Example 1 Even when the raw material fibers of the vapor grown carbonaceous fiber of Example 1 were immersed in water, they did not get wet and floated. Furthermore, even when mixed with epoxy resin and molded, the strength of the molded product did not improve.

Example 2 The vapor-grown carbonaceous fiber of Example 1 was grown at 2500°C for 20 minutes.
An experiment similar to that in Example 1 was conducted using graphitic carbonaceous fibers that had been heat-treated for a minute. At this time, acrylamide was changed from 15% by weight to 16% by weight, and hydroxyethyl acrylate was changed to 7ml%.

The amount of organic part added to the obtained carbonaceous fiber was 9 Da/I.

Example 3 An experiment similar to Example 1 was conducted using vapor-grown carbon fibers (synthesized in a suspended state) having a diameter of 1 to 0.5 μm.

The plasma treatment time was 5 minutes, and the reaction with the organic polymerizable monomer after the plasma treatment was performed using 6 parts by weight of butadiene, 101 parts of acrylamide, 5 parts by weight of styrene,
The mixture was brought into contact with a mixed system of 5 parts by weight of alkylbenzeysulfonic acid and 200 parts by weight of water in a closed system. The reaction temperature is 70
After reacting at °C for 40 minutes, washing and drying were performed.

The amount of organic part added to the obtained carbonaceous fiber was 21rn9/
It was g.

Example 4 The same procedure as in Example 3 was carried out by using 7 parts by weight of methyl methacrylate in place of styrene and raising the reaction temperature to 80°C. The added amount of organic part of the obtained elementary fiber is 18~/y
Met.

Example 5 The carbonaceous fiber used in Example 6 was irradiated with an electron beam of 30 Mrad, and after this treatment, 5 parts by weight of detadiene, 8 parts by weight of acrylonitrile, 5 parts by weight of vinyl chloride, and 5 parts by weight of alkylbenzenesulfone #Jt were added. The mixture was reacted at 60° C. for 30 minutes in a mixed system of 200 parts water and 200 parts water. The amount of organic part added to the obtained carbonaceous fiber was 7 to y/y.

(Effects of the Invention) The carbonaceous fiber of the present invention has good adhesion and wettability with rubber and resin because the organic polymerizable monomer has been added with an appropriate amount of organic moiety through an addition reaction. Therefore, it is easy to combine and mix with these materials, and when used as a composite material, the mechanical properties are favorably improved. Therefore, it is extremely useful as a reinforcing material for resins, rubber, etc. It can also be used as a functional fiber that adsorbs gas and the like.

Claims (1)

[Claims] By adding an organic polymerizable monomer, it has an organic part of 0.01 to 100 mg per gram of carbonaceous fiber and a diameter of 0.
．． 01-4μm carbon fiber