JPH11255843A - Rubber containing silanol - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rubber exhibiting high damping properties, a high breaking elongation and a high breaking strength comprising a rubber containing ethylene groups and a side chain which is bonded to the rubber and bears a silanol on its end. SOLUTION: The titled rubber is constituted of a rubber containing ethylene groups and a side chain bonded to thereto and bearing a silanol, preferably a pyridinium salt of silanol, on its end. That is, the side chain of the rubber bearing a silanol is preferably such that the silanol is bonded to the pyridinium salt. As the rubber containing ethylene groups can be mostly employed a synthetic rubber (e.g. SBR, NBR and the like) which contains ethylene groups and can copolymerize with a vinylpyridine or the like. The rubber is prepared by quaternalizing with an alkyl halide a pyridine ring present in the side chain of the synthetic rubber modified with a vinylpyridine and replacing the halogen in the resultant quaternary salt with a silanol obtained, for example, by the acid treatment of water glass.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rubber having silanol which can be used as a high-damping rubber or the like.

[0002]

2. Description of the Related Art An earthquake is a kind of vibration phenomenon. Therefore, buildings that have slipped and slipped away from the energy of the earthquake will not be broken. However, since every structure has its own vibration response characteristics against earthquake motion, it is possible to reduce the effects of earthquakes on buildings by considering the characteristics of earthquake motion and the characteristics of structures so that they can adapt well. Becomes As one of the building design measures against seismic motion that is currently taking place, the building is insulated from the ground and a soft spring is inserted so that the ground movement is not transmitted directly to the building. There are ways to prevent it. A seismic isolation laminated rubber is known as this soft spring. This seismic isolation rubber is always 100KGF / cm
^It stably supports buildings with a large load of about ² for a long time. In the case of a large earthquake, it is required to have a performance of returning a shocking ground motion to a constant gentle deformation by being softly deformed. For this reason, natural rubber that is soft and rich in rubber-like elasticity that does not easily cause creep is used as the optimum material.

[0003] The currently used laminated rubber is usually a natural rubber-based seismic isolation laminated rubber. The natural rubber-based seismic isolation laminated rubber is obtained by adding a compounding agent such as a filler and a vulcanizing agent to natural rubber, and these compounding agents are compounded by utilizing rubber elasticity. In addition, a separate damper is used in combination to further attenuate the seismic motion, and it becomes possible to suppress excessive displacement of the seismic isolation laminated rubber due to energy consumption during an earthquake.

There are a hysteresis damper and a viscous damper as commonly used dampers. Of the natural rubber-based seismic isolation laminated rubber, the most widely used one is a laminate with lead plugs composed of laminated rubber that is alternately laminated with steel sheet and natural rubber, vulcanized and bonded, and high-purity lead plugs. There is rubber (LRB). This has a structure in which, during an earthquake, the lead plug is sealed in the center of the laminated rubber, so that the lead plug is integrated with the laminated rubber and undergoes plastic deformation. Therefore, the LRB is also a compact seismic isolation device that has all the functions required for the seismic isolation system in the entire device.

[0005] Lead metal is characterized in that it undergoes plastic deformation with a lower stress than other general metals, and has a property such as recrystallization, so that fatigue reduction does not clearly appear. As a result, the LRB is a seismic isolation bearing that integrates the characteristics of seismic isolation rubber required for a seismic isolation structure and the damper function, and is a hybrid seismic isolation bearing that combines the characteristics of laminated rubber with the mechanical characteristics of lead. I can say. But,
Since metal lead is not a harmless metal, other useful materials are required.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a novel organic-inorganic hybrid rubber having characteristics such as high damping.

[0007]

The rubber having silanol of the present invention is characterized by comprising a rubber body having an ethylene group and a side chain having silanol at the end bonded to the rubber body. The rubber having the silanol of the present invention stretches like a candy in an unvulcanized state, and has a high damping property when blended with ordinary rubber.

[0008] The silanol-containing rubber of the present invention preferably has silanol bonded to a pyridinium salt.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The rubber having silanol of the present invention comprises a rubber body having an ethylene group and a side chain having silanol at a terminal bonded to the rubber body. The rubber body having an ethylene group is mainly a synthetic rubber which has an ethylene group and can be copolymerized with vinylpyridine and the like. For example, SBR, N
BR, BR, IB, ethylene propylene rubber (EPM,
EPDM), neoprene rubber (CR), butyl rubber, halogenated butyl rubber and the like can be used. In addition, silanol can be introduced into natural rubber if vinylpyridine is bonded in a predetermined amount or more by graft polymerization.

The silanol is obtained, for example, by bonding a silanol obtained by acid-treating sodium silicate or water glass to a pyridine ring projecting from a side chain of a rubber body as a pyridinium salt. Can be. This silanol is bound to the end of the side chain of the rubber body. More specifically, the pyridine ring present on the side chain of the synthetic rubber modified with vinyl pyridine is quaternarily salified with an alkyl halide, and reacted with the quaternary salt,
It can be formed by substituting halogen bonded to a quaternary salt with silanol. The quaternary chlorination of the pyridine ring can be easily performed in the form of a solution by using latex-like synthetic rubber.

The amount of silanol contained in the rubber body is 2
A range from 0 to 30 is preferred. The amount of silanol depends on the amount of vinylpyridine copolymerized in the synthetic rubber. To synthesize a seismic isolation rubber, it is preferable to use a vinylpyridine-modified synthetic rubber in which about 2% of vinylpyridine is copolymerized. In the case where the amount of the pyridine ring bonded is insufficient, it is also possible to compensate for the insufficient amount by graft-polymerizing vinylpyridine to the rubber.

In order to bond the silanol to the pyridine ring in the rubber body, the pyridine ring is first quaternized. This quaternary chloride is formed by reacting an alkyl halide with a pyridine ring. This reaction can be obtained, for example, by adding a solution of an alkyl halide to a rubber latex containing a pyridine ring. Examples of the alkyl halide include ethyl bromide, propyl bromide, butyl bromide, butyl chloride, propyl chloride and the like.

Next, an acid-treated silicate is added to the latex in which the quaternary salt has been formed, and the halogen of the quaternary salt is replaced with silanol to isolate the rubber. Can be easily formed in two steps. When the rubber containing silanol is not cross-linked, the silanol plays a role of cross-linking between molecules, and has a property of exhibiting a deformation resistance as a soft and high elasticity elastic body. Even after the cross-linking treatment, it has a breaking strength and a hysteresis loss value higher than that of natural rubber as described later. However, there is a problem in the set performance by itself.

The silanol-containing rubber and the silanol-free vinylpyridine-modified synthetic rubber are each treated with 6
When comparing the physical properties of vulcanized rubber compounded with 0% natural rubber,
As shown in the tensile test of FIG. 1, when rubber having silanol is blended with natural rubber (indicated by ●), the breaking elongation and the breaking strength are higher than that of pyridine-modified synthetic rubber containing no silanol (■). In addition, the elongation of the above two tensile-return test,
When the result of the hysteresis loss value calculated from the area in the loop drawn when the tension was released after the tension was reduced to 150% was compared, as shown in FIG. Compared with the hysteresis loss value of natural rubber alone (see NR10 in FIG. 7 described later)
It shows that both have large high attenuation.

When the results of the tensile-return test performed three times in succession (the rubber having silanol in FIG. 3 and the pyridine-modified synthetic rubber not containing silanol in FIG. 4) are compared, the hysteresis loss values (loops) for the second time from the first time are shown. The area containing the silanol decreases as shown in FIG. 3, but the peak value of the hysteresis loss is less likely to decrease as compared with the case where the silanol is not included in FIG. (It almost returns to the initial deformation position as shown in (1)) It can be seen that the physical properties of rubber can be improved by introducing silanol.

The rubber having the silanol (equivalent to LATEX in FIGS. 5 and 6) is vulcanized by changing the compounding ratio to natural rubber (equivalent to NR in FIGS. 5 and 6) containing carbon black, and the breaking strength is obtained. Are shown in FIGS. 5 and 6. FIG. In FIGS. 5 and 6, the lower curves do not include the rubber having the silanol, and it can be seen that the addition of the rubber having the silanol significantly improves the tensile strength at each mixing ratio.

[0017] FIG. 7 shows the results of a pull-back test for each sample in which the mixing ratio of rubber (LATEX) having silanol to natural rubber (NR) containing carbon black was changed from 0:10 to 10: 0. 8 and 9. As shown in FIG. 7, only the case of the natural rubber containing no rubber having silanol shows a loop having a small area below and a low value. The hysteresis loss value was calculated based on the result. The values of the calculation results are shown in the bar graph of FIG.

When only natural rubber (NR) is used, the hysteresis loss value is about 70 and does not reach 100, but any rubber compound containing a silanol-containing rubber (LATEX) has a hysteresis loss value exceeding 150 and exhibits high damping properties. Was. Among them, rubber having natural rubber (NR) and silanol (LA)
The best value was obtained when the mixing ratio with TEX) was 6: 4. The hysteresis loss values of rubbers containing a rubber having silanol at a ratio other than the above are almost the same as shown in the bar graph of FIG. 10 with some errors.

Therefore, as shown in FIG. 10, the rubber having silanol itself (example of LATEX 10: 0) also has a high damping property. For this reason, since the damping property of the rubber having silanol itself is recognized, the use of rubber having silanol as a new seismic isolation rubber can be expected. Therefore, the compounding ratio of the rubber having silanol and the natural rubber (L
ATEX: NR) for each sample crosslinked
The value of the hysteresis loss of the third time of performing the tensile-return test to elongate to% is shown in the bar graph of FIG. The rubbers compounded at the ratios of LATEX: NR = 4: 6 and LATEX: NR = 6: 4, 4: 6 showed good values exceeding 60. In addition, those having a small amount of the rubber containing silanol showed values close to 50. In addition, the bar graph on the left end of FIG. 11 is a value of only natural rubber, and the value of the other rubber compound containing silanol is higher than the bar graph on the left end, and the hysteresis loss is higher than that of natural rubber by compounding the rubber with silanol. Indicates the value.

Similarly, when a rubber containing no silanol and a rubber containing silanol were blended with natural rubber, the rubber blended with silanol showed a higher hysteresis loss value. Generally, it is considered that a set having a large hysteresis loss has a poor setting property. Therefore, the bar graph in FIG. 12 shows the results of examining the degree of the compression set of the samples having the above-mentioned respective mixing ratios. According to the results, the setting property was almost the same as that of the control with 10% rubber having a small compounding ratio of the rubber having silanol.

Therefore, the rubber having the silanol of the present invention can be used as a high damping rubber for seismic isolation rubber.

[0022]

The present invention will be specifically described below with reference to examples. Example 1 Commercially available water glass No. 3 (15.65 g) was diluted with deionized water (1000 ml) to prepare a 0.08 mol / L silicate solution. This silicate solution (50g)
Then, a 2N aqueous solution of sulfuric acid (1-1.3 ml) was added dropwise to the solution, and the solution was adjusted to pH 6-7 and transferred to a separating funnel. Tetrahydrofuran (20 ml) and sodium chloride (10 g) were added to the solution in the separating funnel, and the separating funnel was shaken. Thereafter, the separating funnel was allowed to stand and separated into two layers, and then the upper organic layer was separated. This separation operation was repeated five times.

A solution prepared by dissolving 0.70 g of an alkyl halide (n-propyl bromide) in 10 ml of chloroform was dropped into 140 g of vinylpyridine-modified SBR (vinylpyridine content: 2%) to convert pyridine to a quaternary salt. The tetrahydrofuran solution containing silanol prepared above was added to the quaternized salted reaction solution to cause a reaction.
The precipitate was dried for 2 days to prepare a solid of SBR rubber having silanol.

5 g of SBR rubber having silanol and 45 g of natural rubber (in the case of 1: 9, each sample was prepared by changing the compounding ratio to a predetermined ratio so that the total amount of the samples was 10)
Of carbon black SEAST 600 in a mixture of
g, 2.5 g of activated zinc white, 1 g of a vulcanization accelerator, and 1 g of sulfur, and the mixture was kneaded with a roller at a roll temperature of 50 ° C. using a roll manufactured by Kagaku Kikai Seisakusho to form a sheet. The rubber that has been kneaded is left for one day and then subjected to a JSR-type curast (160 ° C) manufactured by Imanaka Machinery Co., Ltd. to calculate the vulcanization time, and taking this time into account, a press machine (160 ° C)
And vulcanized.

The obtained sample was AR-600 manufactured by ORINTEC.
The strength and elongation and the hysteresis loss were measured using a Tensilon universal testing machine of 0. The results of the tensile test are shown in FIGS.
The results of the pull-back test are shown in FIGS. 7, 8 and 9. The calculated value of the hysteresis loss is shown in the bar graph of FIG. Example 2 Water glass No. 3 (15.65 g) was diluted with deionized water (1000 ml) to prepare a 0.08 mol / L silicate solution. 2N was added to this silicate solution (50 g).
Aqueous solution of sulfuric acid (1 to 1.3 ml) was added dropwise, and the pH
Transferred to a separatory funnel as # 7. Tetrahydrofuran (20 ml) and sodium chloride (1
0 g) is added and the separatory funnel is shaken. After the separation funnel was allowed to stand and separated into two layers, the upper organic layer was separated.

A solution prepared by dissolving 0.65 g of an alkyl halide (n-propyl bromide) in 10 ml of chloroform was dropped into 200 g of a vinylpyridine-modified SBR (vinylpyridine content: 2%), and the SBR was copolymerized with the SBR. The pyridine in the chain was quaternized. The tetrahydrofuran solution containing silicic acid prepared above was added to the reaction solution subjected to the quaternary salification treatment to react the quaternary salt with the silicic acid. The obtained precipitate was dried for 2 days to prepare a solid of a silanol-containing SBR rubber in which silicic acid was bonded to a quaternary salt of pyridine.

To a mixture of 5 g of the obtained silanol-containing synthetic rubber and 45 g of natural rubber (in the case of 1: 9, each of the samples was prepared by changing the compounding ratio to a predetermined ratio), 20 g of carbon black SEAST 600 and 20 g of active zinc were added. Flower 2.5
g, 1 g of a vulcanization accelerator, and 1 g of sulfur, and the mixture was kneaded with a roll at a roll temperature of 50 ° C. using a roll manufactured by Kagaku Kikai Seisakusho to form a sheet. The rubber that has been kneaded is left for one day and then subjected to a JSR-type curast (160 ° C) manufactured by Imanaka Machinery Co., Ltd. to calculate the vulcanization time. An input sample was prepared. With respect to each of the obtained samples, a tensile-return test for returning to the original state until the elongation to 150% was performed three times, and the value of each sample of the hysteresis loss calculated for the third hysteresis loop was shown in the bar graph of FIG.

Further, the compression set showing the setting property is measured by inserting a sheet of each sample into a compression set tester at 70 ° C.
After being kept in the dryer for 24 hours, the change in the sheet thickness of the sample was measured. The results are shown in the bar graph of FIG.

[0029]

The rubber having the silanol of the present invention is superior in the hysteresis loss and the tensile strength of the physical properties to the physical properties of the base-isolated rubber made of the conventional natural rubber. Therefore, the rubber having the silanol of the present invention is useful for use as a high damping rubber.

[Brief description of the drawings]

FIG. 1 SS of rubber with and without silanol
It is a graph of a curve.

FIG. 2 is a graph of a hysteresis loop of a rubber with silanol and a rubber without silanol.

FIG. 3 is a graph of three pull-back tests of a rubber with silanol.

FIG. 4 is a graph of three pull-back tests of rubber without silanol.

FIG. 5 is a graph of an SS curve of a vulcanized rubber produced by changing a mixing ratio of a rubber having silanol and a natural rubber.

FIG. 6 is a graph of an SS curve of a vulcanized rubber prepared by changing a mixing ratio of a rubber having silanol and a natural rubber.

FIG. 7 is a graph showing a hysteresis loop of a vulcanized rubber produced by changing the compounding ratio of a rubber having silanol and a natural rubber.

FIG. 8 is a graph of a hysteresis loop of a vulcanized rubber produced by changing the compounding ratio of a rubber having silanol and a natural rubber.

FIG. 9 is a graph showing a hysteresis loop of a vulcanized rubber produced by changing the compounding ratio of a rubber having silanol and a natural rubber.

FIG. 10 is a bar graph showing a value of hysteresis loss calculated from a hysteresis loop of a vulcanized rubber prepared by changing a compounding ratio of a rubber having silanol and a natural rubber.

FIG. 11 is a bar graph showing a value of hysteresis loss calculated from a hysteresis loop of a vulcanized rubber prepared by changing a compounding ratio of a rubber having silanol and a natural rubber.

FIG. 12 is a bar graph showing values of set properties of a vulcanized rubber prepared by changing a compounding ratio of a rubber having silanol and a natural rubber.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 226: 06)

Claims (2)

[Claims] 1. A rubber having silanol, comprising: a rubber body having an ethylene group; and a side chain bonded to the rubber body and having a silanol at a terminal. 2. The rubber composition according to claim 1, wherein the side chain is a pyridinium salt of silanol.