JP2005060894A - Apparatus for producing grafted base material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus for continuously producing a grafted base material in high efficiency. <P>SOLUTION: The apparatus for producing the grafted base material applies a radical-polymerizable compound solution to a base material such as a textile cloth, a sheet material such as paper or film or fibrous base material, sandwiches the base material with films, presses with a nip roll having adjustable pressure to cause close contact of the films to the base material, applies electron beams and accelerates the polymerization reaction in a post-polymerization zone. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention is effective in providing durable functions such as hydrophilicity, water repellency, moisture absorption / release properties, anti-static properties, adhesiveness, and antibacterial properties to fiber-like fabrics, sheet-like substrates such as paper and films, or fibrous substrates. The present invention relates to an apparatus for producing a grafted base material for imparting it.

  Permanent functionality such as improved texture, hygroscopicity, water absorption, water repellency, substance adsorbing ability, and improved adhesion to dissimilar materials is imparted to fiber-like fabrics, sheet-like substrates such as paper and film, or fibrous substrates As a means for achieving this, the graft polymerization method is a useful method. The main graft polymerization methods known so far include a chemical graft polymerization method using a thermally polymerizable initiator such as peroxide, a graft polymerization method using a low-temperature plasma, and a radiation graft polymerization method. In the chemical graft polymerization method, the substrate is immersed in a treatment solution in which the initiator and radically polymerizable compound are dissolved at the same time, and heat treatment is performed. Therefore, a large amount of homopolymer is produced by the initiator released in the bath, and the washing process is performed. There was a problem that the load on the machine increased and the grafting efficiency was not good. In order to activate the base material in the graft polymerization method using low-temperature plasma, it is necessary to install the base material in a vacuum, and the apparatus becomes large in terms of continuous processing of sheet-like and fibrous base materials. There is a problem.

  In the radiation graft polymerization method, currently industrially usable radiation is gamma rays or electron rays. Gamma rays are generated by radioactive waste, and its treatment is a problem. Furthermore, the facility is very large, the processing cost is high, and it is not practical. On the other hand, electron beams are widely used in the tire industry, the electric wire industry, and the like, and in particular, in recent years, a low energy electron beam irradiation apparatus of 300 kV or less has been developed, and the initial cost of the irradiation apparatus is reduced.

  There is a radiation graft polymerization method called a simultaneous irradiation method described in Non-Patent Document 1. First, the material is impregnated with a radically polymerizable compound, and then radiation such as an electron beam is irradiated in an atmosphere having a low oxygen concentration to cause graft polymerization. However, this method has a problem in that the graft reaction is localized by transpiration because many radically polymerizable compounds are volatile. In the above method, activation of the base material and polymerization initiation reaction occur during irradiation. However, when an electron beam is used, the irradiation time is as short as seconds due to the characteristics of the electron beam, and immediately after irradiation in the air. The polymerization reaction cannot be continued due to exposure, and the grafting rate depends greatly on the degree of impregnation of the radically polymerizable compound, making it difficult to control the grafting rate of the product.

  Many chemically synthesized polymer materials are difficult to impregnate with radically polymerizable compounds. For example, in the case of polyethylene terephthalate (polyester) fiber, etc., in order to impregnate the radically polymerizable compound into the fiber filament due to its high crystallinity, the high temperature condition in which the radically polymerizable compound solution is raised above the glass transition temperature of the substrate. Soak the substrate in a halogen-based solvent such as ethylene dichloride or chlorobenzene or a benzene-based solvent such as benzyl alcohol in advance to swell the fiber, or use a halogen-based solvent in the radical polymerizable compound solution. It is necessary to add benzene solvent. The use of such harmful organic solvents must be avoided due to recent environmental problems.

  On the other hand, as a method of performing electron beam graft polymerization on a polymer substrate having an aromatic ring in the main chain constituting a polymer such as polyethylene terephthalate and polybutylene terephthalate which are stable to radiation such as electron beam, in an atmosphere with an oxygen concentration of 500 ppm or less. Shows a method of contacting a radical polymerizable compound after irradiation with an electron beam (see Patent Document 1). However, even when the oxygen concentration is carried out in an atmosphere of 100 ppm or less, the above method does not provide a sufficient graft rate.

Therefore, the present inventors sealed a fiber fabric provided with a radical polymerizable compound solution between polymer films, irradiated an electron beam from the polymer film, and then performed post-polymerization by heating ( Patent Document 2) is disclosed.
Y. Tabata, Y. Ito and S. Tagawa, “CRC Handbook of Radiation Chemistry”, Boston, p.721 (1991) JP-A-4-146271 Japanese Patent No. 3293301

  In the conventional radiation graft polymerization method described in Non-Patent Document 1, the graft polymerization reaction cannot be efficiently performed in a continuous process. The inventors of the present invention have an activity that easily causes radical polymerization in the base material when irradiated with an electron beam in a state where the base material to which the radical polymerizable compound solution is applied is in close contact between two films, that is, in a film-sealed state. It has been found that the polymerization reaction is initiated in the surface layer as soon as the seed is formed. Thereafter, the film-sealed base material is allowed to stay in a post-polymerization reaction tank for a predetermined time at a predetermined temperature, so that the graft layer generated on the surface of the base material further advances to the inside of the base material, and the thickness of the graft layer increases. I found out. That is, a grafted substrate having a large graft ratio that can be used for functional processing is obtained.

  Using the electron beam graft polymerization method disclosed in Patent Document 2 disclosed by the present inventors, a sheet-like or fibrous long base material such as fiber fabric, paper, film, etc. is continuously conveyed to be uniform and always constant. It aims at providing the grafting base material manufacturing apparatus which can provide a quantity radically polymerizable compound solution to a base material.

  The grafted substrate production apparatus according to the present invention comprises a means for conveying a sheet-like or fibrous substrate made of a polymer material, and a polymerizable compound that imparts a radically polymerizable compound solution to the entire substrate to be conveyed An application means, a film sealing means for bringing the film into both surfaces so as to sandwich the base material to which the radically polymerizable compound solution has been applied, and press-fitting the entire film, and the film in close contact Reaction initiation means for irradiating the substrate with an electron beam to generate active species in the substrate and simultaneously causing a polymerization reaction, and the substrate treated by the reaction initiation means within a range of 0 ° C. to 130 ° C. And a post-polymerization means for accelerating the polymerization reaction in a temperature setting environment.

  Further, the film sealing means conveys an endless belt-like film respectively disposed at both ends of the base material, and adheres to both surfaces of the base material being transported.

  Further, the film sealing means is characterized in that a gap between both end portions of the film adhered to both surfaces of the base material is sealed with the radical polymerizable compound solution leaked from the base material.

  As a result of diligent examination of an apparatus system for continuously performing the above steps, a base material to which a radical polymerizable compound solution is applied is sandwiched between two films, and then the solution is uniformly formed by pressure bonding using a pressure bonding means. The base material and the film come into close contact with the entire material and in the presence of the radical polymerizable compound solution. At this time, since the excess radical polymerizable compound solution leaks at the same time, the application rate of the radical polymerizable compound solution to the substrate can be controlled to be constant and can be uniformly applied to the substrate. In particular, when the substrate is fibrous, the radical polymerizable compound can sufficiently penetrate between the fiber filaments.

  Furthermore, by making the film width slightly wider than the substrate width, preferably by making each end wider by 1 cm or more, the radical polymerizable compound solution leaks into the voids of the film on both ends where the substrate does not exist. By sealing, oxygen in the air that inhibits radical polymerization can be prevented from entering.

  After that, the substrate to which the radical polymerizable compound solution is applied is irradiated with an electron beam in a state of being in close contact between the two films, and then kept in a post-polymerization tank at a predetermined temperature in an air atmosphere for several minutes. Increase graft rate. Thus, grafting is performed uniformly and a substrate having a high graft ratio can be produced.

  Also, long-term continuous operation is possible by transporting the film in the form of an endless belt.

  Hereinafter, embodiments according to the present invention will be described in detail. The embodiments described below are preferable specific examples for carrying out the present invention, and thus various technical limitations are made. However, the present invention is particularly limited in the following description. Unless otherwise specified, the present invention is not limited to these forms.

  FIG. 1 is a diagram showing an outline of an embodiment according to the present invention. This embodiment includes a base material feed mechanism unit 2, a polymerizable compound application mechanism unit 3, a film feed mechanism unit 6, a base material / film seal mechanism unit 7, a polymerization reaction start mechanism unit 8, a post-polymerization mechanism unit 9, and a film recovery The mechanism units are arranged in the order of the mechanism unit 11, the substrate cleaning mechanism unit 12, the substrate drying mechanism unit 14, and the substrate recovery mechanism unit 15.

  The flow of the base material in this embodiment will be described in detail. Here, a long fabric is described as an example of the base material. The fabric 1 is fed from the base material feed mechanism unit 2 and immersed in the radical polymerizable compound solution 4 along the guide roll 22 of the polymerizable compound application mechanism unit 3. In this example, the radically polymerizable compound solution 4 is passed through the dipping tank of the cloth 1 to be conveyed. However, the cloth is made so that the radically polymerizable compound solution 4 passes under a spray device in which the radically polymerizable compound solution 4 is dripped linearly. The radically polymerizable compound solution 4 may be applied to the whole 1.

  Next, when the fabric 1 is unloaded from the polymerizable compound application mechanism unit 3, the fabric 1 is immediately sandwiched from both sides by two films 10 unwound in the vertical direction, and is passed between the nip rolls 7 serving as pressure bonding means. Then, the film 10 is brought into close contact with the fabric 1. At this time, the leaked unnecessary radical polymerizable compound solution 4 flows down along the lower film 10 and is recovered in the recovery container 5. The film 10 is a film that is 5 cm wider on both sides than the width of the fabric 1. By making the film width a little wider than the substrate width, and at least both sides of the film wider than the substrate by 1 cm or more, the radical polymerizable compound solution leaks between the films on both ends where the substrate does not exist. By sealing between the films, it is possible to prevent the entry of oxygen in the air that inhibits radical polymerization. Further, the nip roll 7 is provided with a mechanism for adjusting the pressure-bonding force by hydraulic pressure or the like, and the application rate of the radical polymerizable compound solution to the fabric can be appropriately adjusted to a ratio (30% to 120%). In addition, the use temperature of the radical polymerizable compound solution may be room temperature or may be heated.

  Subsequently, the radically polymerizable compound solution 4 is applied, and the fabric 1 in a state where the film 10 is in close contact is irradiated with an electron beam by the polymerization reaction start mechanism unit 8. At this time, in the polymerization reaction initiation mechanism unit 8, an acceleration voltage of 100 to 800 kV, preferably 120 to 300 kV, and a current of 10 to 100 mA is set with an electron beam irradiation device, preferably with the oxygen concentration of the irradiation atmosphere set to 300 ppm or less. In the range, an irradiation condition is appropriately selected according to the thickness of the fabric and the target graft ratio, and the electron beam is irradiated. Then, an active species is generated in the fabric 1 and at the same time, a polymerization reaction is started.

  The fabric 1 passes through the polymerization reaction start mechanism 8 with the film 10 in close contact, and then can be retained for a predetermined time while being conveyed in the post polymerization mechanism 9 in an air atmosphere set at 50 ° C. The capacity. The post-polymerization mechanism unit 9 promotes the polymerization reaction. What is necessary is just to set the temperature setting of the post-polymerization mechanism part 9 in the range of 0 degreeC to 130 degreeC, More preferably, 40-70 degreeC is good. The residence time may be set in the range of 1 minute to 24 hours, and more preferably 1 minute to 10 minutes.

  Thereafter, the film 10 on both sides of the fabric 1 is peeled off by the film recovery mechanism 11 and wound up, and only the fabric 1 is guided to the substrate cleaning mechanism 12 and washed with warm water as the cleaning liquid 13. Thereafter, the fabric 1 is passed through a cylinder drying type substrate drying mechanism unit 14 to be dried, and the grafted fabric 1 is wound up by the substrate recovery mechanism unit 15. Here, the base material cleaning mechanism unit 12 may select the structure of the cleaning tank and the cleaning liquid as appropriate according to the chemical structure and composition of the radical polymerizable compound solution to be used. The substrate drying mechanism 14 may also use hot air drying. The fabric 1 in which the polymerization reaction has been sufficiently performed in the post-polymerization mechanism unit 9 is obtained by peeling the films on both sides, washing, and drying to obtain a fabric 1 having a high graft ratio in which a graft layer has been formed to the inside of the substrate.

  In the above-mentioned apparatus, it is not necessary to permeate the inside of the base material with the radical polymerizable compound in advance, and graft polymerization inside the base material is possible by post-polymerization means that accelerates the polymerization reaction at a predetermined temperature after electron beam irradiation. Thus, the high graft ratio required for functionalization of the inside of the material can be obtained. In addition, since the base material and the radical polymerizable compound solution are in close contact with the film in a state where air is blocked, at the same time, the radical polymerizable compound of the same quality is always applied, so that the conventional open system Compared with the graft polymerization method, transpiration and uneven distribution of the radical polymerizable compound are less likely to occur, and a uniform grafted substrate can be obtained. In addition, since the application rate of the radical polymerizable compound solution can be varied by means of pressure bonding of the nip roll, the graft rate can be controlled.

  Here, the radical polymerizable compound that can be used is a compound that forms a bond with the polymer radical generated on the substrate by electron beam irradiation, and specifically includes acrylic acid, methacrylic acid, itaconic acid, methacrylsulfonic acid, styrene sulfone. Unsaturated compounds having acidic groups such as acids and their esters, unsaturated carboxylic acid amides such as acrylamide and methacrylamide, unsaturated compounds having glycidyl groups and hydroxyl groups at the ends, unsaturated organic phosphates such as vinylphosphonate, (4) Basic (meth) acrylic acid ester such as tertiary ammonium salt, fluoroacrylate, acrylonitrile and the like can be mentioned, but not limited thereto. These can be used alone or in admixture of two or more.

  In addition, it is desirable to remove dissolved oxygen from the radical polymerizable compound solution by blowing an inert gas such as nitrogen gas in advance.

  Base materials applicable in the present invention include natural fibers such as cotton, hemp, silk, and pulp, regenerated fibers such as rayon and tencel, semi-synthetic fibers such as acetate, and synthetic fibers such as polyester, nylon, polyethylene, and polypropylene. It is a substrate made of fiber, fabric, paper or nonwoven fabric. Moreover, the film-form base material formed from said polymer | macromolecule may be sufficient.

  The film that can be used in the film sealing means is a polymer film having a thickness of 0.01 to 0.2 mm, and a film having an appropriate thickness is used according to the transmission power of the electron beam irradiation apparatus to be used. That's fine. Examples of the material include polyethylene terephthalate and polyolefin. Further, an endless belt-like film, that is, an endless film, may be arranged on the upper and lower sides, and a base material to which a radical polymerizable compound is applied may be adhered between them.

  For example, the post-polymerization mechanism section has a structure in which the length of the fabric in the post-polymerization mechanism section is 100 m in order to retain the fabric at a temperature of 50 ° C. for 5 minutes when the transport speed of the fabric is 20 m / min. There is a need. In short, the length of the fabric in the post-polymerization mechanism section needs to be calculated from the conveyance speed of the fabric and the residence time for promoting the reaction.

  The environment at the time of electron beam irradiation of the present invention is such that the lower the temperature, the better the polymer radical remaining rate, but it may be a normal temperature. Further, the atmosphere may be an inert gas atmosphere such as nitrogen because harmful ozone gas is generated in the presence of oxygen. When performing electron beam irradiation in an air atmosphere, exhaust equipment is required for safety. Further, since the atmosphere of the post-polymerization means is film-sealed, an air atmosphere is sufficient.

  Further, the application mechanism of the radical polymerizable compound solution is preferably a closed system in order to suppress the ingress of oxygen, but an open system is also possible.

Using the above-mentioned apparatus, a 150 cm wide cotton / polyester blend (35/65, warp: 142 / inch, width: 68 / inch) is transported at a transport speed of 5 m / min, and nitrogen gas is blown in advance. It was confirmed that the application rate of 5% acrylic acid aqueous solution to the fabric was about 80% by immersing it in the 5% acrylic acid aqueous solution deoxygenated and passing between nip rolls (mangles) 7 at a pressure of 3 kg / cm ^2. Confirmed in advance. Thereafter, the film is sealed, irradiated with an electron beam under irradiation conditions of an acceleration voltage of 200 kV and an irradiation dose of 40 kGy, and retained for 5 minutes in an air atmosphere at 50 ° C., followed by post-polymerization, washing and drying, and grafted fiber. A fabric was obtained. Table 1 shows the results of the graft reaction.

In Example 1, graft polymerization was performed under the same conditions as in Example 1 except that the concentration of the radical polymerizable compound was changed to a 1% aqueous acrylic acid solution. Table 1 shows the results of the graft reaction.
[Comparative Example 1]
For comparison with the present invention, graft polymerization was carried out under exactly the same conditions as in Example 1 without using film sealing means. Table 1 shows the results of the graft reaction.

The graft ratio and graft efficiency in Table 1 were evaluated by the following methods.
(1) Graft rate The graft rate of the radical polymerizable compound was calculated from the base material dry weight (W1) before the reaction and the base material dry weight (W2) after the graft reaction as follows.
Graft rate = (W2-W1) / W1 * 100 (%)
(2) Grafting efficiency Grafting efficiency is a numerical value that evaluates how much of the radically polymerizable compound supplied to the base material was used in the grafting reaction. Weighing and calculating the graft amount per unit amount of the base material from the above-mentioned graft rate, was calculated as follows.
Graft efficiency = Graft amount / (Amount of radical polymerizable compound) * 100 (%)
From the results in Table 1, compared with Comparative Example 1, Example 1 has a graft ratio of 3 times or more, graft efficiency is 90% or more, and the utilization efficiency of the radical polymerizable compound is very high. . Further, Examples 1 and 2 show that the graft ratio can be controlled by changing the concentration of the radical polymerizable compound.

  FIG. 2 shows another embodiment. In this example, the film 10 has an endless belt shape, and the film 10 is continuously rotated by the driving roller 16, the nip roller 7 and the guide roller 21 in the film delivery mechanism unit 6 and the film recovery mechanism unit 11. Therefore, since the film 10 is not wound up, continuous operation for a long time is possible.

  In recent years, the textile industry has demanded various functionalized fibers such as deodorant antibacterial, comfort, moisture absorption / release, water repellency, and antistatic properties. However, most of the functional processing in the dyeing and arranging business is carried out in the form of post-processing, and the center of the processing method is the method of padding, dipping or coating the functionalized polymer agent on the fiber fabric and heat-treating it. Yes. However, since the functionalizing agent is not chemically bonded to the fiber itself, there is a problem that it has poor durability against washing and friction.

In the film industry, there is a demand for composite films by bonding with dissimilar materials such as metal and joining with sheet materials having different properties such as Teflon (registered trademark) and rubber.
As described above, the graft polymerization method in the sense of grafting is the most suitable means for imparting the properties that the substrate does not have to the surface of the substrate and the inside of the substrate, and the apparatus according to the present invention implements it efficiently. It can be used industrially in terms of what it can do.

It is the schematic which shows the manufacturing flow regarding embodiment of this invention. It is the schematic which shows the manufacturing flow regarding another embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base material 2 Base material delivery mechanism part 3 Polymerizable compound provision mechanism part 4 Radical polymerizable compound solution 5 Recovery container 6 Film delivery mechanism part 7 Base material / film sealing mechanism part 8 Polymerization reaction start mechanism part 9 Post-polymerization mechanism part
10 films
11 Film collection mechanism
12 Substrate cleaning mechanism
13 Cleaning solution
14 Substrate drying mechanism
15 Substrate recovery mechanism
16 Drive roller
21 Guide roll
22 Guide roll

Claims (3)

  There are provided means for conveying a sheet-like or fibrous base material made of a polymer material, a polymerizable compound providing means for applying a radical polymerizable compound solution to the entire substrate to be conveyed, and a radical polymerizable compound solution. In addition, a film seal means for bringing the film into close contact with each other so as to sandwich the base material and press-bonding the whole to each other, and an electron beam is applied to the base material in a state where the film is in close contact with the base. A reaction initiating means for generating an active species in the material and simultaneously causing a polymerization reaction; An apparatus for producing a grafted substrate, comprising: a polymerization means.   2. The grafting according to claim 1, wherein the film sealing means conveys an endless belt-like film respectively disposed at both ends of the base material, and causes the films to adhere to both surfaces of the base material being transported. Base material manufacturing equipment. 3. The film sealing means is characterized in that a gap between both end portions of a film adhered to both surfaces of the base material is sealed with the radical polymerizable compound solution leaked from the base material. The graft | grafting base material manufacturing apparatus as described in 2.

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