KR20140018777A - Nano zinc oxide immobilized nanoporous silica composite material and a rubber composition comprising the same - Google Patents

Abstract

The present invention relates to a nano zinc oxide immobilized nanoporous silica composite material and a rubber composition containing the same. By adding the nanoporous silica composite material to the rubber composition for tires for reinforcing, crosslinking efficiency and dispersing properties are improved, abrasion properties are remarkably improved compare to a case of adding regular nanoporous silica, the production costs for the tires are reduced by remakly reducing the usage of zinc oxide, and the exposure of heavy metal by the abrasion of the tires are reduced.

Description

Nano zinc oxide-immobilized nano-porous silica composite and rubber composition comprising the same {NANO ZINC OXIDE IMMOBILIZED NANOPOROUS SILICA COMPOSITE MATERIAL AND A RUBBER COMPOSITION COMPRISING THE SAME}

The present invention relates to a nanoporous silica composite in which nano zinc oxide is immobilized, and a rubber composition comprising the same. More specifically, zinc oxide nanoparticles are immobilized on a surface of nanoporous silica to be incorporated into a rubber composition for a tire. The present invention relates to a nanoporous silica composite immobilized with nano zinc oxide capable of improving wear performance, and a rubber composition comprising the same.

Research on domestic and international environmental regulations that require the reduction of CO ₂ emissions, the global warming gas generated from the burning of fossil fuels, and the necessity of energy saving. It is becoming.

Conventionally, carbon black is widely used as a reinforcing filler for tires, but carbon black is unable to maintain elasticity at low temperatures, and due to mutual attraction, it tends to agglomerate with each other in an elastomer matrix, thereby restricting dispersion of fillers. The reinforcing properties are lower than the theoretically obtainable level. This tends to increase the concentration of the rubber composition in an uncured state, and when carbon black is present, it tends to be difficult to manufacture due to poor workability. Therefore, carbon black is relatively uncompetitive for producing low cost and low fuel consumption tires.

As a reinforcing inorganic filler, rubber compositions using silica having excellent braking force and rotational resistance on wet roads and carbon black or silica alone are increasing. However, since silica has a strong hydrophilic group, it has high cohesion due to interactions between silica and low dispersibility, so that it may lead to a viscosity increase due to dispersion failure when used in a rubber composition and a drop in rubber properties due to a gelation reaction during long-term storage. In addition, due to the low dispersibility of silica, there is a problem that wear phenomenon occurs in the finished tire made of a rubber composition to which silica is applied.

On the other hand, the vulcanization accelerator contained in the rubber composition containing silica as the reinforcing filler has a disadvantage in that the dispersibility of the silica is low due to the high reactivity with the silica surface and the crosslinking efficiency of the vulcanization accelerator is lowered. Although zinc oxide is used as a vulcanizing agent in rubber compositions, when conventional zinc oxide is added, it has disadvantages of low activity and low crosslinking rate due to low specific surface area. In the case of excessive use due to the flocculation phenomenon, the dispersibility in the rubber composition is lowered, and the dispersibility of zinc oxide is lowered, so that the vulcanization rate is slow in the rubber composition, thereby lowering the productivity.

As the need for fuel saving and environmental protection is critical, there is an urgent need for the development of tires with reduced rolling resistance and good road grip without the side effects of wear resistance.

The present invention is to meet the technical requirements described above, one object of the present invention is to improve the dispersibility of silica and improve the wear properties, increase the cross-linking efficiency of nano zinc oxide and reduce the amount of zinc zinc due to tire wear compared to conventional zinc oxide The present invention provides a nanoporous silica composite having a nano zinc oxide immobilized to reduce the exposure of heavy metals and a method of manufacturing the same.

Another object of the present invention is to use a nano zinc oxide immobilized nano-porous silica composite prepared by the method for preparing nano-porous silica composites immobilized nano zinc oxide as a component of the tire tread rubber composition, grounding performance, wet rotation It is to provide a rubber composition for tire tread that not only improves the resistance performance but also improves the wear performance.

One aspect of the present invention for achieving the above object is a precipitated nano-porous silica, and nano-zinc oxide-fixed nano-porous silica composite in which nano zinc oxide is fixed on the surface of the precipitated nano-porous silica, Precipitated nanoporous silica has a BET surface area of 50-700 m ² / g, pore size of 0.5-40 nm, pore volume of 0.5-2.4 cm 3 / g, particle size of 10-150 μm, and the nano-pores The present invention relates to a nanoporous silica composite having a nano zinc oxide fixed thereon, wherein the silanol groups present on the surface of the silica are 2 to 8 per nm ² .

Another aspect of the present invention comprises the steps of preparing a precipitated nanoporous silica slurry in the form of an aqueous slurry, the pH is neutral;

Preparing a nano zinc oxide slurry in the form of an aqueous slurry;

Mixing the precipitated nanoporous silica slurry and the nano zinc oxide slurry to react by a wet reaction to obtain a nanoporous silica composite having nano zinc oxide fixed thereto;

Separating the nanoporous silica composite to which nano zinc oxide is immobilized from an aqueous medium; And

The present invention relates to a nanoporous silica-fixed nanoporous silica composite comprising the step of drying the nanoporous silica composite is fixed nano zinc oxide.

Another aspect of the present invention has a particle size of 10 ~ 150 ㎛, pore size of 0.5 ~ 40 nm, selected from the group consisting of precipitated porous silica, porous alumina, carbon black, diatomaceous earth, bentonite, talc, magnesium silicate Inorganic particles; And

The present invention relates to a nanoporous inorganic particle composite including nano zinc oxide having a specific surface area of 20 to 100 m ² / g and a particle size of 5 to 150 nm, which is fixed to the surface of the inorganic particles.

Another aspect of the invention is a rubber composition comprising a raw rubber, and at least one reinforcing inorganic filler, wherein the reinforcing inorganic filler comprises at least one silica, the silica being nano zinc oxide on the surface of the precipitated nanoporous silica. It relates to a fixed nano-porous silica composite.

Another aspect of the present invention relates to a tire or a semi-finished product made of rubber for tire production to which the rubber composition is applied.

The nanoporous silica composite having the nano zinc oxide fixed according to the present invention reduces the agglomeration of particles by immobilizing the nanoporous silica to improve dispersibility than conventional nano zinc oxide, thereby increasing the crosslinking efficiency in the rubber composition. In the composite of the present invention, the nano zinc oxide immobilized on the surface of the nanoporous silica decreases the reaction between the silica and the vulcanization accelerator, thereby increasing the crosslinking efficiency of the vulcanization accelerator.

Furthermore, the polarity of the silica is partially or wholly non-polarized by the nano-zinc oxide fixation to suppress the aggregation phenomenon between the silica and increase the interaction between the silica and the rubber, thereby improving the dispersibility of the silica in the rubber in the tire composition, The abrasion performance can be improved.

In addition, when the composite of the present invention is used, the amount of nano zinc oxide used can be significantly reduced to 1/2 to 1/10. It can reduce the manufacturing cost of tires and reduce the exposure of zinc heavy metal due to tire wear around the road.

One embodiment of the invention relates to nanoporous silica composites in which nano zinc oxide is immobilized. Such a composite is a composite in which nano zinc oxide is immobilized on the surface of nanoporous silica.

The nano-porous silica is a silica having a nano-porous structure formed by the three-dimensional network structure of the primary particles, a material having a three-dimensional pore structure. Such nanoporous silicas are described, for example, in "Synthesis of mesoporous silica with superior properties suitable for green tire," A. Hilonga, et al., J. Ind. Eng. Chem. (2012)] can be manufactured according to the method described. Nano zinc oxide is discontinuously physically immobilized on the surface of nanoporous silica.

The method of immobilizing nano zinc oxide on the surface of nanoporous silica is immobilized by the electrical attraction between the negatively charged and relatively positively charged nano zinc oxide due to silanol groups present on the surface of silica. By uniformly mixing the nano zinc oxide slurry in the liquid phase to the nanoporous hydrogel slurry before drying in the manufacturing process of the nanoporous silica, the nano zinc oxide having a positive charge on the surface of the silica having a negative charge is immobilized by electrical attraction. You can do that.

In order to simultaneously perform the function of the reinforcing filler used in the rubber and the role of the support to be achieved in the present invention, it is preferable that the pore size of the nanoporous silica is about 0.5-40 nm, When the pore size is smaller than 0.5 nm, the interlocking between the rubber molecule and the silanol group is relatively difficult, and the absolute value of the negative charge is relatively large, and the positively charged zinc oxide Although the immobilization efficiency is high, there is a problem that the hydrophilicity is high and the dispersibility of the rubber is deteriorated. On the contrary, when the pore size of the nanoporous silica is larger than 40 nm, the silanol group density is relatively too low to help dispersibility, but there is a problem in that the immobilization efficiency is lowered because the absolute value of the negative charge is low. Therefore, in order to increase the immobilization efficiency between the negative charge of the silanol groups present on the silica surface and the positive charge of the nano zinc oxide, an appropriate density of silanol groups is required. In this sense, the silanol groups are 2-8 atoms / nm ^2. It is preferable to adjust between.

The nanoporous silica has a particle size of 10-150 μm, a BET surface area of 50-700 m ² / g, a pore size of 0.5-40 nm, and a pore volume of 0.5-2.4 cm 3 / g. The physical properties of the nanoporous silica can be controlled by controlling the process conditions in the production of nanoporous silica. In the present invention, the particle size of the nano zinc oxide is preferably larger than the size of the pores of the nano-porous silica. When the pore size of the nanoporous silica is too large, the density of the silyl group is lowered, and the negative charge is lowered. As a result, the immobilization efficiency with the nano-zinc oxide is lowered. On the contrary, when the pore size is too small, , The density of the silanol group is increased, which is relatively hydrophilic, which may adversely affect the hydrophobic rubber dispersion

On the other hand, when the BET surface area of the nanoporous silica is less than 50 m ² / g, the number of bonds between the silica and the rubber is reduced, so that the level of bonding with the rubber may be insufficient, on the contrary, the BET surface area of the nanoporous silica is 700 m ² If it exceeds / g, the interaction between the fillers is increased, so that the dispersibility in the rubber matrix may be lowered and the processability may be lowered.

The silanol group present on the surface of the nanoporous silica of the present invention is preferably 2 to 8 per nm ² . On the surface of nanoporous silica If the silanol group has a density of less than 2, the chemical bond between the rubber molecule and the inorganic polymer silica is weakened due to the lowering of the silanol group, which is a reactor to be bonded to the coupling agent when crosslinking with rubber, resulting in low fuel consumption and associated hysteresis loss. It is difficult to improve the properties to be achieved due to the problem of rolling resistance.In contrast, when the density of silanol groups per nm ² exceeds 8, the hydrophilicity of the silica surface increases, so that hydrophobicity decreases dispersibility in rubber elastomer. Cause. Therefore, the density of silanol groups present on the surface of nanoporous silica, which is required for immobilization, should be controlled and used in the range of 2 to 8 per nm ² .

The method for controlling the number of silanol groups on the surface of nanoporous silica is generally synthesized by acid decomposition reaction of sodium silicate (Na ₂ OxSiO ₂ , x = 1 ~ 3.7) with sulfuric acid. Play density can be controlled.

One) Nano pore  In the silica reaction process Silanol  Density Control Method

Sulfuric acid (10-98%) and sodium silicate ([SiO ₂ ] / [Na ₂ O] = 1 to 3.7 mole, 10-30%) are transferred via the injection pump to the intermediate storage port and uniformly through the pumped nozzle Mixed reaction. In order to remove the Na ⁺ and SO ₄ ^{2 -} ions from the slurry in which the gelation reaction proceeds, and to control the silanol groups on the silica surface, the general sol-gel theory lowers the density of the silanol groups. Condensation polymerization at 150 ℃) and basic condition (pH 7-10), and condensation polymerization at relatively low temperature (below 40 ℃) and acidic condition (pH 1-5) to increase the density of silanol groups .

2) Silanol  Density Control Method

The hydrogel in which the physical properties are controlled in the reaction step 1) can control the number of the silanol groups according to the drying method. Generally, the hydrogel is controlled by the temperature, and when dried at 200 ° C or lower in the air, the synthesized silica hydrogel The silanol groups on the surface of the silica are changed into siloxane structures by pyrolysis and maintained at a temperature of about 400 ° C. When the silanol groups are dried at a temperature higher than 200 ° C., The silanol groups present on the surface gradually disappear and ultimately all the silanol groups disappear and the siloxane structure becomes unable to serve as a reinforcing filler used in the tire.

The nano zinc oxide is a zinc oxide nanoparticles having a specific surface area of 20 ~ 100 m ² / g, particle size of 5 ~ 150 nm.

The nano-oxide-fixed nanoporous silica of the present invention can be used as an inorganic filler in vulcanizable rubber compositions or vulcanized rubber compositions, for example, in rubber applications. In order to obtain the optimum reinforcing properties imparted by the inorganic fillers in the tire treads and thus high wear resistance, it is preferred that the inorganic fillers are present in the rubber matrix in the final form as finely as possible and as homogeneously distributed as possible. Nanoporous silica composites in which zinc oxide is immobilized can satisfy these conditions.

In another aspect of the present invention, the particle size is 10 ~ 150 ㎛, pore size is 0.5 ~ 40 nm, inorganic selected from the group consisting of porous silica, porous alumina, carbon black, diatomaceous earth, bentonite, talc, magnesium silicate and the like particle; And nano-porous inorganic particle complexes immobilized on the surface of the inorganic particles and having a specific surface area of 20 to 100 m ² / g and a particle size of 5 to 150 nm. Such nanoporous silica composites are generally powdered and granular, and can be used in various ways as fillers, reinforcing agents, preservatives, vulcanization accelerators, and the like in connection with rubber products such as tarers. Compared to the rubber composition containing general zinc oxide particles or inorganic filler particles such as silica, the rubber composition comprising the composite of the present invention lowers the rolling resistance of low tires and improves the grip on wet roads, Abrasion performance can be improved.

Another aspect of the invention relates to a method for preparing nanoporous silica composites having nano zinc oxide fixed thereto.

First, a nanoporous silica slurry is obtained by a high-speed quantitative reaction system, and the nanoporous silica slurry is washed with water so that the pH of the nanoporous silica slurry is neutral to prepare a nanoporous silica slurry in the form of an aqueous slurry whose pH is neutral. At this time, the pH of the nanoporous silica slurry is typically 6.0 to 7.5, preferably 6.5 to 7.0. In addition, an acidifying agent selected from inorganic acids such as sulfuric acid, nitric acid or hydrochloric acid or organic acids such as acetic acid or formic acid may be optionally added to adjust the pH of the nanoporous silica slurry.

Subsequently, a nano zinc oxide slurry is prepared by dispersing nano zinc oxide having a specific surface area in the form of an aqueous slurry of 20 to 100 m ² / g and a particle size of 5 to 150 nm while stirring in water. In order to improve dispersion stability, various aqueous dispersants such as benzoic acid, PAA, PVP, PMMA, etc. may be added to the nano zinc oxide slurry. The nanofiber zinc slurry maintains stability in the pH range of 6.5-10.

The nanoporous silica slurry and the nano zinc oxide slurry are mixed and reacted by a wet reaction to obtain a nanoporous silica composite having nano zinc oxide fixed thereto. At this time, the content ratio of nanoporous silica: nano zinc oxide may be mixed in a range of 0.5: 99.5 to 99.5: 0.5. The mixed solution is stirred at a temperature of 20 to 90 ° C for 30 to 120 minutes to prepare a nanoporous silica composite in which the nano-sized zinc oxide is fixed by a wet process. At this time, a surfactant such as alkyl ammonium halide may be added as a dispersant in an amount of 0.01 to 0.5% by weight based on the mixture.

The solid and liquid are separated from the aqueous medium by filtering the nanoporous silica composite having the nano zinc oxide fixed thereto using a filter (filter press) with compression means. After separation, the separated nano zinc oxide fixed nanoporous silica cake (Cake) is prepared as a suspension using water.

The suspension is then spray dried or other instant drying to obtain a nanoporous silica composite having nano zinc oxide fixed. When the nanoporous silica solid immobilized with washed nanofiber zinc oxide has a high viscosity, the filter cake can be mixed with water to prepare a suspension, followed by spray drying or instant drying.

Another aspect of the invention relates to a rubber composition usable for tires. The rubber composition of one embodiment of the present invention is a rubber composition comprising a raw rubber and at least one reinforcing inorganic filler, wherein the reinforcing inorganic filler comprises at least one nanoporous silica, and nano zinc oxide is formed on the surface of the nanoporous silica. It is a rubber composition which is a fixed nano zinc oxide nanoporous silica composite.

The raw material rubber is used in a general rubber composition for tires such as natural rubber and styrene-butadiene rubber, and polyisoprene obtained in nature is preferred for natural rubber. As the raw material rubber, natural rubber and synthetic rubber may be mixed rubber mixed in a weight ratio of 50:50. The raw rubber may be a mixed rubber of two or more different kinds of synthetic rubbers. The raw material rubber may be a mixed rubber in which two or more different kinds of synthetic rubbers are mixed in the same weight ratio.

The synthetic rubber is styrene butadiene rubber (SBR), modified styrene butadiene rubber, butadiene rubber (BR), modified butadiene rubber, chlorosulfonated polyethylene rubber, epichlorohydrin rubber, fluorine rubber, silicone rubber, nitrile rubber, hydrogenated nitrile Rubber, Nitrile Butadiene Rubber (NBR), Modified Nitrile Butadiene Rubber, Chlorinated Polyethylene Rubber, Styrene Ethylene Butylene Styrene (SEBS) Rubber, Ethylene Propylene Rubber, Ethylene Propylene Diene (EPDM) Rubber, Chloroprene Rubber, Ethylene Vinyl acetate rubber, acrylic rubber, hydrin rubber, vinyl benzyl chloride styrene butadiene rubber, bromomethylstyrene butyl rubber, maleic acid styrene butadiene rubber, carboxylic acid styrene butadiene rubber, epoxy isoprene rubber, ethylene propylene propylene rubber, carboxyl Acid Nitrile Butadiene Rubber and Brominated Polyisobutyl at least one selected from the group consisting of isoprene-co-paramethyl styrene) can be used.

* The rubber composition for producing the tire of the present invention or semifinished product made of the rubber for tire production is reinforced by a reinforcing inorganic filler comprising nanoporous silica to which the nano zinc oxide of the present invention is fixed.

Inorganic fillers that can be used in addition to the nanoporous silica composite in the present invention, for example, carbon black, alumina, aluminosilicate, calcium carbonate, diatomaceous earth, bentonite, montmorillonite, nontronite, nondelite (beidellite), volkonskoite, hectorite, saponite, sauconite, vermiculite, halloisite, sericite or these It can be selected from a mixture of.

As used herein, the term "phr" means "parts by weight of an individual predetermined component per 100 parts by weight of rubber". Preferably, the content of nano zinc oxide fixed nanoporous silica composite is in the range of 20 to 120 phr, more preferably 30 to 100 phr, even more preferably 60 to 85 phr. The content of the most preferred nanoporous silica composite may vary depending on the nature of the nanoporous silica used and the intended use.

Naturally, the rubber composition of the present invention is a general additive used in the rubber composition for the production of tire treads, such as extending oils, plasticizers, protective agents such as anti-ozone waxes, chemical ozone inhibitors, antioxidants, Crosslinking systems based on antifatigue agents, adhesion promoters, coupling activators, reinforcing resins, methylene acceptors and / or donors, sulfur or sulfur donors and / or peroxides and / or bismaleimides, vulcanization accelerators or vulcanization It may further comprise an activator. In addition, a white filler such as clay particles, bentonite, talc, chalk or kaolin may be added to the composition of the present invention.

Another aspect of the invention relates to tires comprising the rubber composition of the invention and to semifinished products made from rubber for tires, in particular tire treads. Tire treads comprising the rubber compositions of the present invention exhibit high wear resistance, low rolling resistance and high road traction for all road types, giving automobile tires excellent levels of running performance and economy. Therefore, it is possible to meet the stringent tire performance conditions required under the labeling system to be implemented at home and abroad, such as Europe.

Example

Hereinafter, the present invention will be described in detail by examples. However, these are not limited to the scope of the present invention by these as an embodiment of the present invention.

Manufacturing example  One

By the high-speed rectification system, 5-10% sulfuric acid (H ₂ SO ₄ ) and sodium silicate with a SiO ₂ / Na ₂ O molar ratio of 3.4 and a SiO ₂ content of 10-15% are generated by using a high-speed instantaneous nozzle. Sulfuric acid: sodium silicate = 1: 3 equivalent ratio was mixed and polymerized so that the reaction pH was 9.5 at 25 ° C using a continuous polymerization reactor to obtain a nanoporous silica slurry. The obtained nanoporous silica had a BET surface area of 165 to 175 m ² / g, a pore size of 29 to 30 nm, a pore volume of 0.85 m ³ / g, and a particle size of 18 to 20 μm.

To remove the SO ₄ ^-2 , Na ^{+ 1} ions in the obtained nanoporous silica slurry, the solution was filtered with a filter press and then washed with water. The washed nanoporous silica cake was put into a reactor, and water was added thereto so as to have a solid content of 15% .

Nano zinc oxide powder having a specific surface area of 27 to 28.5 m ² / g and a particle size of 90 to 110 nm was added to water so as to have a solid content of 5% in another reactor and stirred for 30 minutes at a temperature of 25 ° C. Was prepared.

The nano zinc oxide slurry was mixed in a nanoporous silica slurry reactor in a ratio of nanoporous silica: nano zinc oxide = 99.5: 0.5, and 0.05% of alkyl ammonium halide surfactant was added thereto as a dispersant, and the mixture was heated at a temperature of 25 ° C. Stirred for a minute and reacted by a wet reaction.

After completion of the reaction, the nanoporous silica slurry to which the nano-zinc oxide was fixed was filtered using a filter press. Subsequently, the filtered nano-porous silica cake having the nano zinc oxide fixed on it is added with water to a solid content of 15% and stirred, followed by a spray dryer having a temperature of 2 to 5 kgf / cm ² nozzle spray pressure and a temperature of 50 ° C. or higher to remove moisture. It was dried using a spray dryer.

Manufacturing example  2

In the same manner as in Preparation Example 1 to obtain a nano-porous silica slurry, it was dried using a dryer. On the other hand, the specific surface area is 27 ~ 28.5m ² / g, the particle size of the mixed nano zinc oxide dried 90 ~ 110nm with the dried nanoporous silica, the ratio of nanoporous silica: nano zinc oxide = 99.5: 0.5 It was put into the reactor in the dried state. Subsequently, the reaction was stirred at room temperature for 60 minutes to obtain a nanoporous silica composite having nano zinc oxide fixed thereto.

Example 1

As shown in the following Table 1, 85 parts by weight of the nanoporous silica composite having the nano-oxide-fixed zinc oxide prepared in Preparation Example 1 was added to 100 parts by weight of the raw rubber, and other silane coupling agent, stearic acid, , An antioxidant, a sulfur vulcanizing agent and a vulcanization accelerator were added and mixed to obtain a rubber composition. In Table 1 below, the content of each component other than rubber is expressed in phr units.

The rubber composition blended in this way was first mixed with a Banbury mixer, except for the vulcanizing agent and the vulcanization accelerator, and then kneaded at an temperature of 60 ° C. or lower for 5 to 10 minutes through an open mill to prepare a sheet. . The prepared sheet, the vulcanizing agent and the vulcanization accelerator are mixed secondly through a Banbury mixer, and then kneaded for 5 to 10 minutes at a temperature of 60 ° C. or less using an open mill, and 10 minutes at 160 ° C. in a hot press. It was vulcanized to prepare a rubber specimen having a thickness of 20 mm.

With respect to the obtained specimens, various properties such as scorch, rheometer, wear degree, viscoelastic properties, etc. were evaluated by the following method, and the results are shown in Table 2 below.

Example 2

To prepare a rubber composition and the measurement of the physical properties of the rubber specimens were prepared in the same manner as in Example 1 except that the nanoporous silica composite having the nano zinc oxide fixed as shown in Table 1 was increased to 86 parts by weight, scorch, Rheometer, Abrasion, viscoelastic properties were measured and the results are shown in Table 2 together.

Example 3

As in the mixing ratio of Table 1, except that the nanoporous silica composite in which nano zinc oxide is fixed was increased to 86.5 parts by weight, the same procedure as in Example 1 was carried out to prepare a rubber composition and a rubber specimen for measurement of physical properties, and overall physical properties The results of the evaluation are shown in Table 2 together.

Comparative Example 1

In the same manner as in Table 1, except that carbon black and silica were used as inorganic fillers for the raw material rubber, and conventional zinc oxide was used as a vulcanization accelerator. Rubber specimens were prepared, the overall physical properties were evaluated, and the results are shown in Table 2 together.

Comparative Example  2

Except for reducing 50% of nano zinc oxide instead of conventional zinc oxide was prepared in the same manner as in Comparative Example 1 to prepare a rubber composition and rubber specimens for measuring the physical properties, the physical properties were evaluated and the results are shown in Table 2 below. .

division Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 S-SBR ^{1 )} 85 85 85 85 85 BR ^{2 )} 15 15 15 15 15 Carbon Black ^{3 )} 20 20 20 20 20 Silica 85 85 - - - Nano ZnO + Nanoporous Silica Composite - - 85.5 86 86.5 Silane Coupling Agents ^{4 )} 13.6 13.6 13.6 13.6 13.6 Stearic acid One One One One One Existing ZnO ^{5 )} 3 - - - - Nano ZnO ^{6 )} - 1.5 - - - Process oil (RAE) 42 42 42 42 42 Processing aid (A-60) ^{7 )} 2 2 2 2 2 Antioxidant 6PPD ^{8 )} 2.5 2.5 2.5 2.5 2.5 Wax 2 2 2 2 2 Antioxidant (TMQ) ^{9 )} 1.5 1.5 1.5 1.5 1.5 Sulfur 1.5 1.5 1.5 1.5 1.5 Vulcanization Accelerator (CBS) ^{10 )} 1.5 1.5 1.5 1.5 1.5 Vulcanization Accelerator (MBTS) ^{11 )} 1.6 1.6 1.6 1.6 1.6

¹⁾ S-SBR: Styrene-butadiene rubber with styrene content and vinyl content of more than 30%

²⁾ BR: Neodymium Butadiene Rubber

³⁾ Carbon black: N-134 (Columbian Chemicals Co., Ltd.)

⁴⁾ Silane coupling agent: X-50 S ^® Bis (triethoxysilylpropyl) polysulfide

⁵⁾ Existing ZnO: Hanil Synthetic Chemistry

⁶⁾ Nano ZnO: Nano Zinc Oxide with Particle Size of 100nm

⁷⁾ Processing aid: STRUKTOL ^® A 60, zinc soap of unsaturated fatty acids

⁸⁾ Antioxidant: 6PPD, N- (1,3-Dimethybutyl) -Nphenyl-p-phenylenediamine

⁹⁾ Anti aging agent, TMQ: Polymerized dihydroquinoline

¹⁰⁾ Vulcanization accelerator, CBS: N-Cyclohexylbenzo thiazole

¹¹⁾ Vulcanization accelerator, MBTS: 2-mercapto-benzothiazole

division Comparative Example 1 Comparative Example 2 Example 1 Example 2 Example 3 Scotch
(at < RTI ID = 0.0 & t ₅
[min-sec] 27.5 24.5 28.6 29.2 29.9 Rheometer
(at 160 ℃) T ₄₀
[min-sec] 5.4 5.4 5.2 5.0 4.9 Seal
Properties Hardness 70 71 72 72 72 M-300% [kgf / cm ² ] 102 101 109 115 119 Tensile Strength [kgf / cm ² ] 203 201 213 220 225 Elongation rate [%] 500 480 530 540 540 Tear strength [kgf / mm] 44 43 47 48 49 Wear Index 100 96 115 123 125 Viscoelastic tanδ at 0 ℃ 0.492 0.490 0.509 0.513 0.515 tanδ at 60 ℃ 0.206 0.210 0.201 0.199 0.193

[Property evaluation method]

* Hardness is measured with Shore A hardness to standard DIN 53505

* M-300%, tensile strength, elongation and tear strength are measured by ASTM D412 test method using Instron tensile tester.

* Viscoelasticity was measured at -80 ~ 70 ℃ under 10Hz frequency using GABO tester. Tan δ at 0 ° C. is an index of wet traction on wet road surfaces of tires, indicating that the higher the value, the better the grip on wet road surfaces. The tan δ at 60 ° C is used as an index of automobile fuel economy due to the rolling resistance of the tire. The lower the value, the better the fuel efficiency.

* The wear index is a LAMBOURN wear tester based on JIS K 6264. At room temperature, 30% of the sliding ratio and 2.0kg of load were rotated and the loss of worn rubber was indexed based on Comparative Example 1 (100). It shows abrasion performance.

As confirmed through Table 2, in the case of applying the nano-porous silica composite of the nano-zinc oxide of the present invention can be seen that the scorch time is long, which means that the scorch stability is excellent. The dispersibility of the silica in the rubber composition was increased and the braking performance and the rolling resistance on the wet road surface were improved and the abrasion resistance was improved as compared with Comparative Example 1 in which zinc oxide and silica were added.

Furthermore, it can be seen that the physical properties of the tensile strength and modulus are increased by improving the effect of vulcanization reactivity of the active agent by increasing the dispersibility of zinc oxide in the rubber composition. The increase of the tear strength is due to the increase of the bonding force between the rubbers, the aggregation of the silica is suppressed and the dispersibility is improved.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and changes may be made by those skilled in the art to which the present invention pertains. Therefore, the true technical protection scope of the present invention will be defined by the appended claims.

Claims (10)

preparing a precipitated nanoporous silica slurry in the form of an aqueous slurry wherein the pH is neutral;
Preparing a nano zinc oxide slurry in the form of an aqueous slurry;
Mixing the precipitated nanoporous silica slurry and the nano zinc oxide slurry to react by a wet reaction to obtain a nanoporous silica composite having nano zinc oxide fixed thereto;
Separating the nanoporous silica composite to which nano zinc oxide is immobilized from an aqueous medium; And
A method of manufacturing a nano-zinc oxide-fixed nanoporous silica composite, comprising drying the separated nano-zinc oxide-fixed nanoporous silica composite.
The method of claim 1, wherein the precipitated nanoporous silica has a BET surface area of 50 ~ 700 m ² / g, a pore size of 0.5 ~ 40 nm, a pore volume of 0.5 ~ 2.4 cm 3 / g, particle size of 10 ~ 150 μm, wherein the silanol groups present on the surface of the nanoporous silica are 2 to 8 per nm ² of nano zinc oxide-fixed nanoporous silica composite. The method of claim 1, wherein the nano zinc oxide has a specific surface area of 20 to 100 m ² / g, and has a particle size of 5 to 150 nm.
A rubber composition comprising a raw rubber and at least one reinforcing inorganic filler, wherein the reinforcing inorganic filler comprises at least one silica, the silica being nanoporous silica having nano zinc oxide fixed on the surface of the precipitated nanoporous silica. Rubber composition, characterized in that the composite.
The reinforcing inorganic filler according to claim 4, wherein the reinforcing inorganic filler is carbon black, alumina, aluminosilicate, calcium carbonate, diatomaceous earth, bentonite, montmorillonite, nontronite, nondelite, beidelite, volconscote ( at least one member selected from the group consisting of volkonskoite, hectorite, saponite, sauconite, vermiculite, halloisite and sericite Rubber composition, characterized in that it further comprises. The rubber composition of claim 4, wherein the nano zinc oxide fixed nanoporous silica composite is included in an amount of 20 phr to 120 phr.
The rubber composition according to claim 4, wherein the nano zinc oxide has a specific surface area of 20 to 100 m ² / g and a primary particle of 5 to 150 nm.
The method of claim 4, wherein the precipitated nanoporous silica has a particle size of 10 ~ 150 ㎛, BET surface area of 50 ~ 700 m ² / g, pore size of 0.5 ~ 40 nm, pore volume of 0.5 ~ 2.4 cm 3 / g, characterized in that the rubber composition.
The rubber composition according to claim 4, wherein the silanol groups present on the surface of the nanoporous silica are 2 to 8 per nm ² .
10. A tire comprising the rubber composition of any one of claims 4-9.