KR100824666B1 - Manufacturing method of an adhesive comprising tannin - Google Patents

Abstract

The present invention is a pine tree ( Pinus) The present invention relates to a method for producing an adhesive for tire fiber cords having a tannin-formaldehyde-latex composition composed of tannin compound-containing extracts extracted from rigida ) as a main raw material.

The adhesive for tire fiber cords of the present invention is an adhesive using a natural resource composed of tannin compound-containing extracts extracted from Rigida pine tree as a main raw material, unlike conventional adhesives prepared using synthetic resins derived from petroleum resources. As a result, conventional synthetic resin adhesives can be substituted.

Tannin, Adhesive, Tire, Rigi Pine

Description

Manufacturing method of adhesive agent for tire fiber cord containing a tannin compound {MANUFACTURING METHOD OF AN ADHESIVE COMPRISING TANNIN}

The present invention relates to a method for producing an adhesive for tire fiber cords containing a tannin compound, and more specifically, to the present invention, Pinus pine ( Pinus) The present invention relates to a method for producing an adhesive for tire fiber cords having a tannin-formaldehyde-latex composition composed of tannin compound-containing extracts extracted from rigida ) as a main raw material.

Tires should be designed to take account of physical property degradation due to repetitive rotational movements, especially adhesion between rubber and reinforcement cords. Thus, a steel cord or fiber cord is inserted into the belt, carcass and bead portion of the tire in order to improve the structure holding force of the tire and maximize the function. As described above, the structure of each part maintained through the insertion of the cord should be able to support heavy loads, and the stability, durability, lifespan, and economy of the tire may be determined according to the adhesion state between the rubber and the cord applied to each part. As long as it is considered a very important factor. Cords embedded in rubber have significantly different properties from rubber, so the stress on the tires and the heat generated during driving are likely to concentrate at the interface between these two materials. Therefore, only when the cord and rubber are well bonded to transfer stress and heat, the applied force and generated heat are properly dissipated and the tire can be used safely for a long time.

In particular, the fiber cord is designed to bond synthetic fibers between rubbers to reinforce the parts requiring strength, and synthetic fibers such as nylon, polyester, and rayon are used, but such synthetic fibers are compatible with rubber (COMPATIBILITY). There is almost no problem in combining. Therefore, various adhesives have been proposed to properly bond or bond synthetic fiber materials and rubbers, which are incompatible with each other. [Korea Patent Publication No. 385569, Republic of Korea Patent Publication No. 1997-0010856] is commonly used. As the latex, a mixed latex such as styrene-butadiene copolymer latex, vinylpyridine-styrene-butadiene terpolymer copolymer latex or natural rubber latex is generally used.

However, in the composition of the RFL adhesive, since resorcinol is a raw material obtained from a petroleum resource, an increase in the manufacturing cost of the adhesive and a shortage of products may be expected due to an increase in the crude oil price and exhaustion of the crude oil resource. Therefore, the research on the adhesive composition of the new material that can replace the resorcinol steadily progressed, for example, Korean Patent Publication Nos. 1991-6618, 1991-6998, 1992-474, 1992-2647, etc .; Among them, Korean Patent Publication No. 1992-474 proposes an epoxy adhesive composition, and the adhesive composition is treated with high impact strength, environmental resistance, high temperature and low temperature performance, flexibility, and the like, which are required for automobile dense line bonding of SMC parts. It is known to satisfy the characteristics, Korean Patent Publication No. 1992-2647 provides an adhesive composition composed of a mixture of latex, aromatic nitroso compound and polymaleimide compound. However, the adhesive compositions presented in the present invention also do not fundamentally solve the above-mentioned problems in that the main raw material is mainly obtained from mineral resources.

Therefore, the present inventors have studied a novel material that can replace the conventional adhesive prepared by using a raw material derived from petroleum resources, and as a result, formaldehyde and tannin components have high reactivity in the conventional RFL adhesive composition. Paying attention to growing pine tree ( Pinus) The present invention was completed by preparing an adhesive of a tannin-formaldehyde-latex composition containing a tannin compound-containing extract extracted from rigida ) and confirming the adhesive strength and adhesion form of the adhesive.

An object of the present invention is to provide a method for producing an adhesive for tire fiber cords, the tannin compound-containing extract of which is extracted from Rigida pine.

Another object of the present invention is the pine wood ( Pinus) rigida), the compound tannin extract containing 60 to 90% by weight and 37% formalin solution for 10 to 40 in a tannin-formaldehyde resin produced in weight percent, 20 to 60% by weight of the tannin-formaldehyde resin and styrene derived from butadiene- It is to provide a method for producing a tire fiber cord adhesive consisting of 40 to 80% by weight of vinyl pyridine latex.

In order to achieve the above object, the present invention is a pine tree ( Pinus) rigida), the compound tannin extract containing 60 to 90% by weight and 37% formalin solution for 10 to 40 in a tannin-formaldehyde resin produced in weight percent, 20 to 60% by weight of the tannin-formaldehyde resin and styrene derived from butadiene- Provided is a method for producing an adhesive for tire fiber cords having a tannin-formaldehyde-latex composition, consisting of 40 to 80% by weight of vinylpyridine latex.

More specifically, the manufacturing method of the tire fiber cord adhesive of the present invention is 1) Rigi pine ( pinus) rigida ) The skin was dried and pulverized to prepare a tannin powder, and 100 parts by weight of the tannin powder was mixed with 500 to 800 parts by weight of distilled water, and stirred by adding 0.1 to 0.5 parts by weight of sodium carbonate and 1 to 5 parts by weight of sodium sulfite. , The mixture is allowed to stand for 24 to 72 hours at room temperature, and the phase separated solution is filtered to dry the filtrate under vacuum to prepare a tannin compound-containing extract,

2) 60 to 90% by weight of the prepared tannin compound-containing extract was dissolved in distilled water, and then added to 10 to 40% by weight of 37% formalin solution to prepare a mixed solution.

3) Condensation reaction with the basic solution prepared by adding a 10% caustic soda solution to the mixed solution to prepare a tannin formaldehyde resin,

4) 40 to 80% by weight of styrene-butadiene-vinylpyridine latex is added to 20 to 60% by weight of the prepared tannin formaldehyde resin, followed by aging at room temperature.

The mixed solution of step 1) is prepared at a concentration of 3 to 10 g / dl.

The basic solution of step 2) is prepared at a pH of 5 to 10, the condensation reaction is carried out at 10 to 60 ℃, more preferably at 20 to 40 ℃.

The present invention is made of tannin-formaldehyde-latex using the tannin compound-containing extract as a main raw material from the extraction method to obtain a high yield of the tannin compound-containing extract extracted from Rigida pine, to provide an adhesive having excellent adhesive strength, The adhesive can be used in a wide range of applications where conventional RFL adhesives are used. In particular, it is useful for the adhesion of tires composed of a composite of rubber and fiber.

Hereinafter, the present invention will be described in detail.

The present invention provides an adhesive for tire fiber cords containing a tannin compound represented by the following formula (1) extracted from Rigida pine.

The present invention is a pine tree ( Pinus) It provides a method for producing a tire fiber cord adhesive containing a tannin compound-containing extract, extracted from rigida ). More specifically, 1) Pine tree ( pinus) rigida ) The skin was dried and pulverized to prepare a tannin powder, and 100 parts by weight of the tannin powder was mixed with 500 to 800 parts by weight of distilled water, and stirred by adding 0.1 to 0.5 parts by weight of sodium carbonate and 1 to 5 parts by weight of sodium sulfite. , The mixture is allowed to stand for 24 to 72 hours at room temperature, and the phase separated solution is filtered to dry the filtrate under vacuum to prepare a tannin compound-containing extract,

2) 60 to 90% by weight of the prepared tannin compound-containing extract was dissolved in distilled water, and then added to 10 to 40% by weight of 37% formalin solution to prepare a mixed solution.

3) Condensation reaction with the basic solution prepared by adding a 10% caustic soda solution to the mixed solution to prepare a tannin formaldehyde resin,

4) The styrene-butadiene-vinylpyridine latex 40 to 80% by weight is added to 20 to 60% by weight of the prepared tannin formaldehyde resin, and then dispersed and aged at room temperature. Provided is a method for producing a tire fiber cord adhesive.

The present invention is a pine tree ( Pinus) As an extract containing a tannin component extracted from rigida ), the tannin component is water-soluble and high reactivity with formaldehyde component is known among the conventional RFL adhesive components, the tannin obtained in the high yield is the initial raw material of the adhesive It is easy and inexpensive to provide a competitive adhesive.

Adhesive for tire fiber cords produced by the manufacturing method of the present invention is the Rigida pine ( Pinus rigida), the compound tannin extract containing 60 to 90% by weight and 37% formalin solution for 10 to 40 in a tannin-formaldehyde resin produced in weight percent, 20 to 60% by weight of the tannin-formaldehyde resin and styrene derived from butadiene- It is an adhesive of tannin-formaldehyde-latex composition which consists of 40-80 weight% of vinylpyridine latex.

The adhesive of the tannin-formaldehyde-latex composition of the present invention does not contain a resorcinol component and, unlike a conventional adhesive using a synthetic resin derived from petroleum resources, is an adhesive using natural resources, and an adhesive for tire fiber cords. Useful as

1 is a preferred embodiment using an adhesive of the tannin-formaldehyde-latex composition of the present invention, styrene butadiene rubber (c) in the center, the adhesive (b) and PET of the present invention on both sides of the styrene butadiene rubber It is a film of a dual structure which laminates a fiber (a). In addition, the adhesive (b) of the present invention is laminated and bonded on the fiber (a) of the lower PET, and a single structure in which styrene butadiene rubber (c) is coated on the adhesive is also possible.

FIG. 2 shows that in the film structure of the preferred embodiment, the adhesive portion is replaced by the adhesive of the present invention, the conventional RFL adhesive and the adhesive in which the RFL adhesive composition resorcinol and tannin component are prepared in a molar ratio of 1: 1. It is the result of measuring the maximum average adhesive strength with respect to the specimen forming time for vulcanizing styrene-butadiene rubber about each film comprised. The adhesive of the present invention exhibits excellent adhesive strength with respect to the adhesive in which the resorcinol and tannin components are prepared in a molar ratio of 1: 1. Therefore, the tannin-formaldehyde-latex adhesive of the present invention not only eliminates the problem pointed out by eliminating the use of resorcinol, but also the adhesive strength of the adhesive, so that the conventional RFL adhesive is used. Alternative use across a wide range of applications.

In the method for producing an adhesive for tire fiber cords of the present invention, step 1) is a process for preparing a tannin compound-containing extract, pine needles ( pinus) rigida ) The skin was dried and pulverized to prepare a tannin powder, and 100 parts by weight of the tannin powder was mixed with 500 to 800 parts by weight of distilled water, and stirred by adding 0.1 to 0.5 parts by weight of sodium carbonate and 1 to 5 parts by weight of sodium sulfite. , The mixture is allowed to stand for 24 to 72 hours at room temperature, and the phase separated solution is filtered to dry the filtrate under vacuum to prepare a tannin compound-containing extract.

Sodium carbonate in the above is to prepare an alkaline solution, the sodium sulfite is used as a reducing agent, when sodium sulfite is used in less than 1 part by weight, there is no sufficient reducing effect, even if used in excess of 5 parts by weight There is no reducing effect.

It is understood that the tannin extraction method of the present invention can be applied in the same manner as the pine tree other than Rigida pine, to extract the tannin component, but in the embodiment of the present invention, the cork and cork of the Rigida pine ( Cork carbium and phloem are included. Rigi Pine ( Pinus) rigida ) is native to North America, has a low quality of timber and high rosin, so it is useful but grows well anywhere. It is an evergreen coniferous tree that is wild in the mountains of Korea, and has the advantage of providing abundant materials. In particular, the tannin compound is obtained in a yield of 90% or more by the extraction method of the present invention, it is possible to provide an adhesive which is easy to purchase the raw material of the adhesive from the high yield tannin compound, and cheap and competitive.

In the preparation method of the present invention, when preparing the mixed solution in step 2), it is possible to apply a conventional method that can be solubilized as much as possible, it will be understood that it is possible to perform the step of filtering the undissolved foreign matter. Can be.

In the step 2), the 37% formalin solution is preferably used in an amount of 10 to 40% by weight. At this time, when the amount is less than 10% by weight, the reaction rate is considerably slow and the complete curing reaction is not possible. The further use is meaningless since it no longer affects the reaction.

In addition, the mixed solution prepared in step 2) is preferably maintained at a concentration of 3 to 10 g / dl, more preferably 7 to 10 g / dl concentration. At this time, if the concentration of the solution is less than 3 g / dl concentration, there is a disadvantage that the reaction does not occur or the reaction rate is too slow due to the long gel time, whereas, if the concentration exceeds 10 g / dl, the gel time is too fast, the process reaction It is not preferable because there is a problem that is difficult to adjust.

In addition, in the manufacturing method of the present invention, the step 3) is preferably prepared by adding a 10% caustic soda solution to a basic solution of pH 5-10, more preferably pH 6-9. In this case, when the solution is less than pH 5, the gel time is long, when the solution is more than pH 10, the gel time is too fast, it is pointed out that it is difficult to control the reaction in the process ( Fig. 3 ).

Although it can be confirmed by a conventional method capable of preparing a solution in the pH range shown above, as an example thereof, a pH meter or pH paper may be used after 10 seconds have elapsed after base addition with continuous stirring. In addition, the condensation reaction in step 3) is preferably performed at 10 to 60 ° C, more preferably at 20 to 40 ° C.

Then, in the production method of the present invention, in step 4) 40 to 80% by weight of styrene-butadiene-vinylpyridine latex is added to the tannin formaldehyde resin. At this time, when the styrene-butadiene-vinylpyridine latex is less than 40% by weight, the amount of the resin is relatively large compared to the latex, and the cured adhesive is not easily brittle, and the adhesive strength between the adhesive and the rubber is lowered. When it exceeds 80% by weight, the content of tannin in the adhesive of tannin-formaldehyde-latex composition is relatively lowered, thereby lowering the adhesive strength and eventually lowering the mutual binding force between the adhesive and the fiber cord.

Hereinafter, the present invention will be described in more detail with reference to Examples.

This embodiment is intended to illustrate the present invention in more detail, and the scope of the present invention is not limited to these examples.

One. Tannin  detach

< Example  1> Tannin  detach

Pitch pine (pinus rigida ) peeled and dried in vacuo to remove moisture and then pulverized using a blender. Silicone oil bath after adding 100 g of the pulverized pine powder, 700 ml of distilled water, 0.4 g of sodium carbonate (Na ₂ CO ₃ ) and 4 g of sodium sulfite (Na ₂ SO ₃ ) to a 1,000 ml reaction vessel equipped with a stirrer. The mixture was stirred at 95 to 100 ° C. for 3 hours. After stirring, the reaction vessel was sealed and left for about 72 hours at room temperature to separate the phases. After confirming phase separation, the filtrate in which pine powder was dissolved in distilled water and pine powder which was not dissolved by filtration through a filter paper were separated. The filtrate was dried in vacuo and the powder was analyzed by infrared spectroscopy [IR (KBr); υ = 1610, 1112 cm ⁻¹ ].

2. Manufacturing of adhesive for tire fiber cord

< Example  2> Tannins Preparation of adhesives of formaldehyde-latex composition 1

236 g of distilled water and 11 g of the tannin compound-containing extract extracted in Example 1 were mixed in a 1000 ml flask equipped with a stirrer, and dissolved well at 30 ° C., and the undissolved foreign substance was filtered. Thereafter, 16.4 ml of 37% formalin solution was added to the flask to prepare a mixed solution having a concentration of 7 g / dl. 3 g of a 10% caustic soda solution was added to the mixed solution to prepare a basic solution having a pH of 7, followed by condensation reaction at 23 ° C. for 2 hours. After condensation synthesis of tannin-formaldehyde (TF) resin through this process, 244 g of styrene-butadiene-vinylpyridine latex was added to disperse well and aged at room temperature for 24 hours to prepare an adhesive. The prepared adhesive was stored in a cold place until use.

< Example  3> Tannins Preparation of Adhesives of Formaldehyde-Latex Composition 2

An adhesive having a tannin-formaldehyde-latex composition was prepared in the same manner as in Example 2, except that the 10% caustic soda solution was added to prepare a basic solution having a pH of 5.3, and condensation reaction at 23 ° C.

< Example  4> Tannins Preparation of Adhesives of Formaldehyde-Latex Composition 3

An adhesive having a tannin-formaldehyde-latex composition was prepared in the same manner as in Example 2, except that the 10% caustic soda solution was added to prepare a basic solution having a pH of 6.0 and condensation reaction at 23 ° C.

< Example  5> Tannins Preparation of Adhesives of Formaldehyde-Latex Composition 4

An adhesive having a tannin-formaldehyde-latex composition was prepared in the same manner as in Example 2, except that the 10% caustic soda solution was added to prepare a basic solution having a pH of 9.0 and condensation reaction at 23 ° C.

< Example  6> Tannins Preparation of Adhesives of Formaldehyde-Latex Composition 5

When preparing the tannin formaldehyde resin, except that the condensation reaction temperature was carried out at 10 ℃, it was carried out in the same manner as in Example 2 to prepare an adhesive of the tannin-formaldehyde-latex composition.

< Example  7> Tannins Preparation of Adhesives of Formaldehyde-Latex Composition 6

When preparing the tannin formaldehyde resin, except that the condensation reaction temperature was carried out at 60 ℃, it was carried out in the same manner as in Example 2 to prepare an adhesive of the tannin-formaldehyde-latex composition.

< Experimental Example  1> Measurement of adhesive strength of adhesive

In order to measure the maximum average adhesive strength of the film produced using the adhesive prepared in Example 2 was carried out as follows.

As shown in Figure 1 , the styrene butadiene rubber (c) is located in the center, to prepare a double-structured film to laminate the adhesive (b) and PET fibers (a) prepared in Example 2 on both sides of the styrene butadiene rubber It was.

In addition, in the same film structure as above, the adhesive part is prepared by a conventional RFL adhesive or a film composed of the RFL adhesive composition resorcinol and an adhesive whose tannin component is manufactured in a molar ratio of 1: 1, and for each film, styrenebutadiene The maximum average adhesive strength was measured according to the specimen molding time to vulcanize the rubber. At this time, in order to compare with conventional RFL adhesive, polyester-based hydrophobic PET fibers were introduced, and the PET fibers were immersed in 0.05% NaOH solution for 10 minutes and then surface-dried and then bonded. Table 1 and Figure 2 shows the specimen fracture mode for the crosslinking time between the films using the prepared adhesive. In this case, the specimen fracture pattern is referred to as IF (Interfacial Failure), in which the upper part of the PET film is separated from the double film structure of FIG. .

As shown in Table 1 and Figure 2, when the RFL adhesive and the adhesive mixed with resorcinol and tannin in a 1: 1 molar ratio, the adhesive breakdown type shows all IF irrespective of the crosslinking time as shown in FIG. The bond strength was significantly lower. On the other hand, in case of Example 2, a slight CF fracture occurred at the initial crosslinking time, showing a relatively high adhesive strength, and a maximum CF strength with maximum CF fracture at a crosslinking time of 9 minutes.

< Experimental Example  2> Adhesive Characteristics by Addition of 10% Caustic Soda

By varying the amount of 10% caustic soda added in Examples 2 to 5, the viscosity was measured using a Brookfield viscometer for the tannin-formaldehyde resin prepared tannins. The measurement results are shown in Table 2 and FIG. 3 .

As shown in Table 2, when preparing the tannin formaldehyde resin, the reaction rate increases according to the OH concentration of 10% caustic soda added. That is, as the pH concentration was increased, a fast gelation phenomenon was confirmed. In the case of the tannin formaldehyde resin prepared at pH 5.3, gelation occurred after 7.5 hours, whereas the gelation occurred at 2 hours when prepared at pH 9.0. This is because the phenol ring is activated as a nucleophile in the flavonoid ring of tannin with increasing pH concentration.

< Experimental Example  3> Adhesive Characteristics According to Reaction Temperature

The viscosity of the tannin-formaldehyde-latex adhesive prepared in Examples 2 and 6 to 7 was measured using a Brookfield viscometer. The measurement results are shown in Table 3 and FIG. 4 .

As shown in Table 3, when the tannin formaldehyde resin was prepared, it was confirmed that the reaction temperature was performed to affect the gelation rate. When the reaction temperature was 60 ° C., the gel time was 30 minutes, while the reaction temperature was 10. When proceeded to C, it gelled after 6 hours. That is, as the reaction temperature increases, the molecular movement becomes more active, so the gel time decreases with the increase of the reaction temperature, and the adhesive strength increases because the viscosity immediately before gelation increases rapidly.

As a result, the present invention provides an economical adhesive raw material using natural resources by providing an extraction method to obtain a tannin compound-containing extract extracted from Rigida pine in high yield.

In another aspect, the present invention is composed of tannin-formaldehyde-latex using the tannin compound-containing extract as the main raw material extracted from the Rigida pine, and by providing an adhesive having excellent adhesive strength, the adhesive is a wide range of conventional RFL adhesive is used Can be used as an alternative to the field. In particular, it is useful for the adhesion of tires composed of a composite of rubber and fiber.

1 is a view showing a preferred embodiment using an adhesive of the tannin-formaldehyde-latex composition of the present invention,

Figure 2 is a result showing the maximum average adhesive strength for the adhesive of the tannin-formaldehyde-latex composition of the present invention,

Figure 3 is the result of measuring the adhesive properties according to the amount of 10% caustic soda when preparing the adhesive of the present invention,

Figure 4 is the result of measuring the adhesive properties according to the condensation reaction temperature when the adhesive of the present invention.

Claims (4)

Rigi Pine ( Pinus) rigida ) The skin was dried and pulverized to prepare a tannin powder, and 100 parts by weight of the tannin powder was mixed with 500 to 800 parts by weight of distilled water, and stirred by adding 0.1 to 0.5 parts by weight of sodium carbonate and 1 to 5 parts by weight of sodium sulfite. , The mixture is allowed to stand for 24 to 72 hours at room temperature, and the phase separated solution is filtered to dry the filtrate under vacuum to prepare a tannin compound-containing extract, 60 to 90% by weight of the prepared tannin compound-containing extract was dissolved in distilled water, and then added to 10 to 40% by weight of 37% formalin solution to prepare a mixed solution. Condensation reaction with a basic solution prepared by adding a 10% caustic soda solution to the mixed solution to prepare a tannin formaldehyde resin, The tannin-formaldehyde-latex composition of 20 to 60% by weight of the prepared tannin formaldehyde resin is added by dispersing 40 to 80% by weight of styrene-butadiene-vinylpyridine latex, and then matured at room temperature. Manufacturing method of adhesive for tire fiber cords. The method of claim 1, wherein the mixed solution of step 1) is prepared at a concentration of 3 to 10 g / dl. The method of claim 1, wherein the basic solution of step 2) has a pH of 5 to 10. The method of claim 1, wherein the condensation reaction of step 2) is performed at 10 to 60 ° C.

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