Polymer compound, method for preparing modified and conjugated diene-based polymer using the same, and modified and conjugated diene-based polymer

Abstract

The present invention relates to a polymer compound used as a polymer modifier, a conjugated diene-based polymer including a functional group derived therefrom, and a method for preparing a modified and conjugated diene-based polymer using the polymer compound. A rubber modifier compound obtained therefrom is used as a modifier for rubber, particularly, as a modifier of a conjugated diene-based polymer and is bonded to a chain of the conjugated diene-based polymer to easily introduce a functional group having affinity with a filler.

Claims

1. A polymer compound comprising a constituent unit represented by the following Formula 1: ##STR00014## in Formula 1, X.sub.1 and X.sub.2 are each independently a derived substituent from a compound containing C.sub.1-10alkyl, amine, ester, nitrile, benzophenone, acryl, vinyl, styrene, styrenacryl, or aryl, which is unsubstituted or substituted with at least one substituent selected from the group consisting of halogen, C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl, wherein the C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl is optionally substituted with a halogen, X.sub.3 is represented by the following Formula 2: ##STR00015## in Formula 2, R.sub.1 is ester, R.sub.2 is C.sub.1-20alkyl, and a is an integer of 1 to 10, X.sub.4 is represented by the following Formula 3: ##STR00016## in Formula 3, R.sub.3 is C.sub.1-6alkylene, ester, or C.sub.6-10arylene, R.sub.4 and R.sub.5 are each independently C.sub.1-10alkyl, or are combined with each other to form a C.sub.3-10 ring structure, and b is an integer of 1 to 8, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, p is 1 to 70, and A.sub.1 to A.sub.4 are each independently a hydrogen atom, or C.sub.1-3 alkyl, wherein X.sub.1 to X.sub.4 are different from each other.

2. The polymer compound of claim 1, wherein in Formula 1, X.sub.1 is C.sub.1-10alkyl, ester or alkylaryl substituted with halogen.

3. The polymer compound of claim 1, wherein in Formula 1, X.sub.2 is C.sub.6-10aryl unsubstituted or substituted with C.sub.1-3alkyl or C.sub.3-10cycloalkyl.

4. The polymer compound of claim 1, wherein the polymer compound comprising the constituent unit represented by Formula 1 comprises a constituent unit represented by the following Formula 4 or Formula 5: ##STR00017## in Formula 4 and Formula 5, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, and p is 1 to 70.

5. The polymer compound of claim 1, wherein the polymer compound is a modifier for a conjugated diene-based polymer.

6. A modified and conjugated diene-based polymer comprising a functional group derived from a polymer compound comprising a constituent unit represented by the following Formula 1: ##STR00018## in Formula 1, X.sub.1 and X.sub.2 are each independently a derived substituent from a compound containing C.sub.1-10alkyl, amine, ester, nitrile, benzophenone, acryl, vinyl, styrene, styrenacryl, or aryl, which is unsubstituted or substituted with at least one substituent selected from the group consisting of halogen, C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl, wherein the C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl is optionally substituted with a halogen, X.sub.3 is represented by the following Formula 2: ##STR00019## in Formula 2, R.sub.1 is ester, R.sub.2 is C.sub.1-20alkyl, and a is an integer of 0 to 10, X.sub.4 is represented by the following Formula 3: ##STR00020## in Formula 3, R.sub.3 is C.sub.1-6alkylene, ester, or C.sub.6-10arylene, R.sub.4 and R.sub.5 are each independently C.sub.1-10alkyl, or are combined with each other to form a C.sub.3-10 ring structure, and b is an integer of 1 to 8, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, p is 1 to 70, and A.sub.1 to A.sub.4 are each independently a hydrogen atom, or C.sub.1-3alkyl.

7. The modified and conjugated diene-based polymer of claim 6, wherein the polymer compound comprising the constituent unit represented by Formula 1 comprises a constituent unit represented by the following Formula 4 or Formula 5: ##STR00021## in Formula 4 and Formula 5, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, and p is 1 to 70.

8. The modified and conjugated diene-based polymer of claim 6, wherein the polymer comprises from 100 ppm to 10,000 ppm of a silane group based on a total amount of the polymer.

9. The modified and conjugated diene-based polymer of claim 6, wherein the polymer comprises 40 wt % or less of a derived unit from an aromatic vinyl-based monomer.

10. The modified and conjugated diene-based polymer of claim 6, wherein the polymer has a number average molecular weight of 10,000 g/mol to 1,000,000 g/mol.

11. A method for preparing the modified and conjugated diene-based polymer of claim 6, the method comprising: 1) polymerizing conjugated diene-based monomers, or an aromatic vinyl-based monomer and a conjugated diene-based monomer in the presence of an organo-alkali metal compound in a hydrocarbon solvent to prepare an active polymer in which an alkali metal is bonded to at least one terminal thereof; 2) reacting the active polymer with a polymer compound comprising a constituent unit represented by the following Formula 1 to obtain a first modified polymer; and 3) reacting the first modified polymer with a silane-based compound: ##STR00022## in Formula 1, X.sub.1 and X.sub.2 are each independently a derived substituent from a compound containing C.sub.1-10alkyl, amine, ester, nitrile, benzophenone, acryl, vinyl, styrene, styrenacryl, or aryl, which is unsubstituted or substituted with at least one substituent selected from the group consisting of halogen, C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl, wherein the C.sub.1-20alkyl, C.sub.3-20cycloalkyl, and C.sub.6-30aryl is optionally substituted with a halogen, X.sub.3 is represented by the following Formula 2: ##STR00023## in Formula 2, R.sub.1 is ester, R.sub.2 is C.sub.1-20alkyl, and a is an integer of 0 to 10, X.sub.4 is represented by the following Formula 3: ##STR00024## in Formula 3, R.sub.3 is C.sub.1-6alkylene, ester, or C.sub.6-10arylene, R.sub.4 and R.sub.5 are each independently C.sub.1-10alkyl, or are combined with each other to form a C.sub.3-10 ring structure, and b is an integer of 1 to 8, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, p is 1 to 70, and A.sub.1 to A.sub.4 are each independently a hydrogen atom, or C.sub.1-3alkyl.

12. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the polymer compound comprising the constituent unit represented by Formula 1 comprises a constituent unit represented by the following Formula 4 or Formula 5: ##STR00025## in Formula 4 and Formula 5, m, n, o and p represent a molar ratio of each repeating unit, where m+n+o+p is 100, m is 1 to 50, n is 0 to 50, o is 1 to 50, and p is 1 to 70.

13. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the organo-alkali metal compound is used in a molar ratio of 0.01 mmol to 10 mmol based on 100 g of a total of the monomers.

14. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the polymerizing in step 1) is conducted by further adding a polar additive.

15. The method for preparing the modified and conjugated diene-based polymer of claim 14, wherein the polar additive is added in an amount of 0.001 parts by weight to 10 parts by weight based on 100 parts by weight of a total of the monomers.

16. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the polymer compound is used in a molar ratio of 0.1 mol to 10 mol based on 1 mol of the organo-alkali metal compound.

17. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the silane-based compound is used in a molar ratio of 0.001 mol to 10 mol based on 1 mol of the polymer compound.

18. The method for preparing the modified and conjugated diene-based polymer of claim 11, wherein the silane-based compound is any one selected from the group consisting of vinyl chlorosilane, vinyltrimethoxysilane, vinyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, p-styryltrimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, 3-acryloxypropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethylbutylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, 3-chloropropyltrimethoxysilane, 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, bis(triethoxysilylpropyl)tetrasulfide, and 3-isocyanatopropyltriethoxysilane, or a mixture of at least two thereof.

Description

Preparation Example 1

(1) To a 5 L reactor equipped with a jacket for controlling temperature, a solvent condensing apparatus and an agitating apparatus, 60.1 g (0.39 mol) of 4-(chloromethyl)styrene (CMSt), 164.1 g (1.58 mol) of styrene (SM), 174.2 g (1.34 mol) of 2-methoxyethylacrylate (MEA), 101.6 g (0.63 mol) of N,N-dimethylaminomethylstyrene (DMAMS), and 2 kg of tetrahydrofuran (THF) were injected, followed by elevating the temperature to 65 C. and stirring for 5 minutes. Then, in a 500 ml beaker, 33.6 g (0.2 mol) of 2,2-azobisisobutyronitrile (AIBN) was dissolved in 168.0 g of tetrahydrofuran, and the resultant solution was injected to the reactor, followed by stirring at 65 C. for 12 hours for performing the reaction to prepare Modifier A which is a polymer compound including a constituent unit represented by the following Formula (i):

(2) ##STR00012##

(3) in Formula (i), m is 10, n is 40, o is 34, and p is 16.

Preparation Example 2

(4) To a 5 L reactor equipped with a jacket for controlling temperature, a solvent condensing apparatus and an agitating apparatus, 88.0 g (0.58 mol) of 4-(chloromethyl)styrene (CMSt), 140.2 g (1.35 mol) of styrene (SM), 160.2 g (1.23 mol) of 2-methoxyethylacrylate (MEA), 111.6 g (0.69 mol) of N,N-dimethylaminomethylstyrene (DMAMS), and 2 kg of tetrahydrofuran (THF) were injected, followed by elevating the temperature to 65 C. and stirring for 5 minutes. Then, in a 500 ml beaker, 35.1 g (0.21 mol) of azobisisobutyronitrile (AIBN) was dissolved in 168.0 g of tetrahydrofuran, and the resultant solution was injected to the reactor, followed by stirring at 65 C. for 12 hours for performing the reaction to prepare Modifier B which is a polymer compound including a constituent unit represented by Formula (i), where m is 15, n is 35, o is 32, and p is 18.

Preparation Example 3

(5) To a 5 L reactor equipped with a jacket for controlling temperature, a solvent condensing apparatus and an agitating apparatus, 46.5 g (0.30 mol) of 4-(chloromethyl)styrene (CMSt), 135.0 g (1.30 mol) of styrene (SM), 158.7 g (1.22 mol) of 2-methoxyethylacrylate (MEA), 159.8 g (0.99 mol) of N,N-dimethylaminomethylstyrene (DMAMS), and 2 kg of tetrahydrofuran (THF) were injected, followed by elevating the temperature to 65 C. and stirring for 5 minutes. Then, in a 500 ml beaker, 34.8 g (0.21 mol) of azobisisobutyronitrile (AIBN) was dissolved in 168.0 g of tetrahydrofuran, and the resultant solution was injected to the reactor, followed by stirring at 65 C. for 12 hours for performing the reaction to prepare Modifier C which is a polymer compound including a constituent unit represented by Formula (i), where m is 8, n is 34, o is 32, and p is 26.

Preparation Example 4

(6) To a 5 L reactor equipped with a jacket for controlling temperature, a solvent condensing apparatus and an agitating apparatus, 34.9 g (0.23 mol) of 2-(chloroethyl)acrylate (CEA), 134.8 g (1.29 mol) of styrene (SM), 158.5 g (1.22 mol) of 2-methoxyethylacrylate (MEA), 171.8 g (1.07 mol) of N,N-dimethylaminomethylstyrene (DMAMS), and 2 kg of tetrahydrofuran (THF) were injected, followed by elevating the temperature to 65 C. and stirring for 5 minutes. Then, in a 500 ml beaker, 32.6 g (0.2 mol) of azobisisobutyronitrile (AIBN) was dissolved in 168.0 g of tetrahydrofuran, and the resultant solution was injected to the reactor, followed by stirring at 65 C. for 12 hours for performing the reaction to prepare Modifier D which is a polymer compound including a constituent unit represented by the following Formula (ii):

(7) ##STR00013##

(8) in Formula (ii), m is 6, n is 34, o is 32, and p is 28.

(9) The synthesis of Modifier A to Modifier D, which are polymer compounds prepared in Preparation Examples 1 to 4, respectively, was identified via molecular weight analysis, and the results are shown in Table 1 below.

(10) In particular, the molecular weight analysis was conducted by GPC analysis under conditions of 40 C. In this case, two columns of PLgel Olexis and one column of PLgel mixed-C manufactured by Polymer Laboratories Co. Ltd. were used in combination as columns, and newly replaced columns were all mixed bed type columns. In addition, polystyrene (PS) was used as a GPC standard material for calculating the molecular weight.

(11) TABLE-US-00001 TABLE 1 Number average molecular Molecular Composition weight weight Division Monomer used (molar ratio) (g/mol) distribution Modifier A CMSt/SM/ 10/40/34/16 6600 1.8 MEA/DMAMS Modifier B CMSt/SM/ 15/35/32/18 6400 2.2 MEA/DMAMS Modifier C CMSt/SM/ 8/34/32/26 7000 2.1 MEA/DMAMS Modifier D CEA/SM/ 6/34/32/28 6300 1.9 ODMA/DMAMS

Example 1

(12) To a 10 L autoclave reactor, 250 g of styrene, 750 g of 1,3-butadiene, 7 kg of cyclohexane, and 0.8 g of ditetrahydrofurylpropane as a polar additive were added, and the internal temperature of the reactor was elevated to 70 C. When the internal temperature of the reactor reached 60 C., 0.5 g of an n-hexane solution with 1.53 wt % of n-butyllithium was injected into the reactor, and an adiabatic reaction with heating was performed. The adiabatic reaction with heating was ended, and after about 40 minutes, 20 g of a polymerization solution was separately taken, and added to 100 g of isopropyl alcohol to precipitate and use for identifying the properties of a polymer before modification. Then, 32.8 g of Modifier A prepared in Preparation Example 1 was dissolved in 200 g of tetrahydrofuran and injected into the reactor, followed by performing the reaction for 30 minutes. 20 g of the reaction product was separately taken and added to 100 g of isopropyl alcohol to precipitate and use for identifying the properties of a first modified polymer. After that, 5.88 g of 3-aminopropyltrimethoxysilane was diluted in 10 g of cyclohexane and injected, followed by additionally reacting at 80 C. for 1 hour. The reaction was quenched using isopropyl alcohol, and 45 ml of a solution of 0.3 wt % of butylated hydroxytoluene (BHT) as an antioxidant dissolved in hexane was added thereto. The polymer thus obtained was injected to hot water heated with steam, stirred to remove solvents, and roll dried to remove remaining solvents and water to prepare a modified styrene-butadiene copolymer.

Example 2

(13) A modified styrene-butadiene copolymer was prepared by performing the same method described in Example 1 except for using 32.8 g of Modifier B prepared in Preparation Example 2 instead of Modifier A.

Example 3

(14) A modified styrene-butadiene copolymer was prepared by performing the same method described in Example 1 except for using 32.8 g of Modifier C prepared in Preparation Example 3 instead of Modifier A.

Example 4

(15) A modified styrene-butadiene copolymer was prepared by performing the same method described in Example 1 except for using 32.8 g of Modifier D prepared in Preparation Example 4 instead of Modifier A.

Comparative Example 1

(16) To a 10 L autoclave reactor, 250 g of styrene, 750 g of 1,3-butadiene, 7 kg of cyclohexane, and 0.8 g of ditetrahydrofurylpropane as a polar additive were added, and the internal temperature of the reactor was elevated to 70 C. When the internal temperature of the reactor reached 60 C., 0.5 g of an n-hexane solution with 1.53 wt % of n-butyllithium was injected into the reactor, and an adiabatic reaction with heating was performed. The adiabatic reaction with heating was ended, and after about 40 minutes, 20 g of a polymerization solution was separately taken, and added to 100 g of isopropyl alcohol to precipitate and use for identifying the properties of a polymer before modification. Then, 32.8 g of Modifier A prepared in Preparation Example 1 was dissolved in 200 g of tetrahydrofuran and injected into the reactor, followed by performing the reaction for 30 minutes. The reaction was quenched using isopropyl alcohol, and 45 ml of a solution of 0.3 wt % of butylated hydroxytoluene (BHT) as an antioxidant dissolved in hexane was added thereto. The polymer thus obtained was injected to hot water heated with steam, stirred to remove solvents, and roll dried to remove remaining solvents and water to prepare a modified styrene-butadiene copolymer.

Comparative Example 2

(17) A styrene-butadiene copolymer was prepared by performing the same method described in Comparative Example 1 except for using 2.8 g of an n-hexane solution with 10 wt % of tetrachlorosilane as a coupling agent instead of Modifier A.

Comparative Example 3

(18) A modified styrene-butadiene copolymer was prepared by performing the same method described in Example 1 except for using 11.3 g of 10 wt % 3-(N,N-dimethylamino)propyl trimethoxysilane solution instead of Modifier A.

Experimental Example 1

(19) With respect to each of the copolymers prepared in Examples 1 to 4 and Comparative Examples 1 to 3, the styrene derived unit content and the vinyl content in each copolymer, the weight average molecular weight (Mw), the number average molecular weight (Mn), the maximum peak molecular weight (Mp), the molecular weight distribution (MWD, Mw/Mn), the mooney viscosity (MV) and, the silicon (Si) content were measured. The results are listed in Table 2 below.

(20) 1) Analysis of Styrene Derived Unit Content and Vinyl Content

(21) The styrene derived unit (SM) content and the vinyl content in each copolymer were measured by using NMR.

(22) 2) Analysis of Molecular Weight

(23) The weight average molecular weight (Mw, g/mol), the number average molecular weight (Mn, g/mol), and the maximum peak molecular weight (Mp, g/mol) were measured by GPC analysis under conditions of 40 C. The molecular weight distribution (Mw/Mn) was calculated as the ratio of the weight average molecular weight and the number average molecular weight thus measured, and a coupling number (Mp1/Mp2) was obtained by respectively measuring the maximum peak molecular weight after modification (Mp1) and the maximum peak molecular weight before modification (Mp2) and dividing. In this case, two columns of PLgel Olexis and one column of PLgel mixed-C manufactured by Polymer Laboratories Co. Ltd. were used in combination as columns, and newly replaced columns were all mixed bed type columns. In addition, polystyrene (PS) was used as a GPC standard material when calculating molecular weights.

(24) 3) Analysis of Mooney Viscosity

(25) The mooney viscosity (MV, (ML1+4 @100 C.) of each copolymer was measured by using MV2000E (Alpha Technologies Co., Ltd.) using Large Rotor at a rotor speed of 20.02 rpm. In this case, a specimen used was stood at room temperature (233 C.) for 30 minutes or more, and 273 g of the specimen was collected and put in a die cavity, and then, Platen was operated, and pre-heated at 100 C. for 1 minute, and the mooney viscosity was measured for 4 minutes.

(26) 4) Analysis of Silicon (Si) Content

(27) The silicon content of each copolymer was measured by using ICP-OES Optima8 300 DV (Perkin Elmer Co., Ltd.).

(28) TABLE-US-00002 TABLE 2 GPC Mooney Styrene Vinyl Mw Mn Coupling viscosity Si Division (wt %) (wt %) (g/mol, 10.sup.4) (g/mol, 10.sup.4) Mw/Mn number (MV) (ppm) Example 1 24 46 54 34 1.6 2.4 70 523 Example 2 25 47 54 32 1.7 2.6 69 762 Example 3 25 46 61 34 1.8 2.5 74 369 Example 4 25 46 51 32 1.6 2.2 64 283 Comparative 24 46 56 35 1.6 2.4 71 <10 Example 1 Comparative 24 45 59 37 1.6 2.4 74 56 Example 2 Comparative 24 46 45 32 1.4 1.8 56 145 Example 3

(29) In Table 2, the coupling number represents that a polymer chain was coupled or modified by a modifier, and the greater the value is, the higher the ratio of the coupling or modification is.

(30) As shown in Table 2, all coupling numbers of Examples 1 to 4 according to exemplary embodiments of the present invention were greater than 2, and from the results, the modification was secured.

Experimental Example 2

(31) The physical properties of a rubber composition including each copolymer of Examples 1 to 4 and Comparative Examples 1 to 3 and molded products manufactured therefrom, were comparatively analyzed. The results are listed in Table 3 below.

(32) 1) Preparation of Rubber Composition

(33) Each rubber composition was prepared via a first stage mulling, a second stage mulling and a third stage mulling. In this case, the amounts used of materials excluding a modified and conjugated diene-based copolymer were shown based on 100 parts by weight of the modified and conjugated diene-based copolymer. In the first stage mulling, 100 parts by weight of each copolymer, 70 parts by weight of silica, 11.02 parts by weight of bis(3-triethoxysilylpropyl)tetrasulfide as a silane coupling agent, 33.75 parts by weight of a process oil (TDAE), 2.0 parts by weight of an antiaging agent (TMDQ), 2.0 parts by weight of an antioxidant, 3.0 parts by weight of zinc oxide (ZnO), 2.0 parts by weight of stearic acid, and 1.0 part by weight of wax were mixed and mulled under conditions of 80 rpm by using a banbury mixer equipped with a temperature controlling apparatus. In this case, the temperature of the mulling apparatus was controlled, and a first compound mixture was obtained at a discharge temperature of 140 C. to 150 C. At the second stage mulling, the first compound mixture was cooled to room temperature, and 1.75 parts by weight of a rubber accelerator (CZ), 1.5 parts by weight of a sulfur powder, and 2.0 parts by weight of a vulcanization accelerator were added to the mulling apparatus and mixed at a temperature of 60 C. or less to obtain a second compound mixture. Then, the second compound mixture was molded at a third stage mulling, and vulcanized at 180 C. for t90+10 minutes using a vulcanization press to prepare each vulcanized rubber.

(34) 2) Mooney Viscosity

(35) The mooney viscosity (MV, (ML1+4 @100 C.)) for each of the first compound mixture (first stage mulling) and the second compound mixture (second stage mulling) was measured by using MV2000E manufactured by Alpha Technologies Co., Ltd. using Large Rotor at a rotor speed of 20.02 rpm. In this case, a specimen used was stood at room temperature (233 C.) for 30 minutes or more, and 273 g of the specimen was collected and put in a die cavity, and then, Platen was operated, and pre-heated at 100 C. for 1 minute, and the mooney viscosity was measured for 4 minutes.

(36) 3) Analysis of Payne Effect (AG') Analysis

(37) The Payne effect was measured using 7 g of each vulcanized rubber with strain sweep of 0.04% to 40% in a rate of 1 Hz at 60 C. by using RPA 2000 manufactured by ALPHA Technologies Co., Ltd, and was shown as the difference between a minimum value and a maximum value. In this case, if the Payne effect decreases, dispersibility of a filler such as silica is improved.

(38) 4) Tensile Properties

(39) The tensile properties were measured by manufacturing each specimen (thickness of 25 mm, length of 80 mm) and measuring tensile strength when broken and tensile stress when elongated by 300% (300% modulus) of each specimen according to an ASTM 412 tensile test method. Particularly, a Universal Test machine 4204 tensile tester (Instron Co., Ltd.) was used, and measurement was performed at room temperature at a rate of 50 cm/min, to obtain a tensile strength value and a tensile stress value when elongated by 300%.

(40) 5) Viscoelasticity Properties

(41) The viscoelasticity properties were measured by using a dynamic mechanical analyzer (TA Co., Ltd.). Tan was measured by changing deformation at each measurement temperature (0 C. to 60 C.) with a twist mode and a frequency of 10 Hz. If the Tan at a low temperature of 0 C. is high, braking force is good, and if the Tan at a high temperature of 60 C. is low, hysteresis loss is small, low rolling resistance (fuel consumption ratio) is good. Resultant values were shown as Index values with the measured value of a rubber composition including the copolymer of Comparative Example 3 as 100. The viscoelasticity was improved according to the increase of the Index value.

(42) 6) Abrasion Resistance

(43) Abrasion resistance was measured by using a DIN abrasion measuring apparatus. Resultant values were compared as Index values with the measured value of a rubber composition including the copolymer of Comparative Example 3 as 100. The abrasion resistance was improved according to the increase of the Index value.

(44) TABLE-US-00003 TABLE 3 Comparative Comparative Comparative Division Example 1 Example 2 Example 3 Example 4 Example 1 Example 2 Example 3 Mooney First stage 71 68 64 62 69 66 62 viscosity mulling (MV) Second stage 58 57 56 54 62 61 54 mulling Payne effect (G) 0.44 0.43 0.42 0.45 0.56 0.58 0.46 Tensile 300% 104 108 104 102 98 97 100 properties modulus (Index) Tensile 103 103 101 101 97 96 100 strength (Index) Viscoelasticity Tan at 104 106 103 104 94 92 100 properties 0 C. Tan at 108 110 106 105 93 82 100 60 C. Abrasion resistance 103 104 99 101 100 97 100 (Index)

(45) From the results of Table 3, the rubber compositions including the modified styrene-butadiene copolymers of Example 1 to Example 4, which were prepared using the polymer compound according to the present invention as a modifier, showed the same or better 300% modulus and tensile strength, increased braking force (0 C. Tan ) by 3% to 6% with respect to wet roads, and largely improved low rolling resistance (60 C. Tan ) by 5% to 10%, when compared to those of the rubber composition including the modified styrene-butadiene copolymer of Comparative Example 3, which was prepared using the conventional common modifier.

(46) Meanwhile, the rubber compositions including the modified styrene-butadiene copolymers of Example 1 to Example 4 according to exemplary embodiments of the present invention showed improved wet traction, fuel consumption ratio and mechanical properties when compared to those of the rubber compositions including the unmodified and conjugated diene-based polymers of Comparative Example 1 and Comparative Example 2.

(47) In addition, the specimens prepared from the rubber compositions including the modified styrene-butadiene copolymers of Example 1 to Example 4 according to exemplary embodiments of the present invention showed largely decreased values in Payne effect when compared to the specimens prepared using the rubber compositions including the unmodified or modified styrene-butadiene copolymers of Comparative Example 1 to Comparative Example 3, and from the results, it can be found that the dispersibility of silica in the rubber compositions including the modified styrene-butadiene copolymers of Example 1 to Example 4 was better than that of silica in the rubber compositions of Comparative Example 1 to Comparative Example 3. From the results, it can be found that the modified styrene-butadiene copolymers of Example 1 to Example 4 according to exemplary embodiments had excellent affinity with silica, i.e., a filler.