[BIS(TRIHYDROCARBYLSILYL)AMINOSILYL]-FUNCTIONALIZED STYRENE AND A METHOD FOR ITS PREPARATION

Abstract

The invention relates to [bis(trihydrocarbylsilyl)aminosilyl]-functionalized styrene and a method for its preparation. The invention further relates to the use of the styrene derivative in the preparation of a copolymer thereof. The styrene derivative is preferably used as comonomer in the production of elastomeric copolymers. Alternatively, or additionally, it is used in the preparation of a polymerization initiator.

Claims

1. A styrene derivative of Formula (I) ##STR00008## wherein R.sup.1 is selected from the group consisting of: a) a single bond; b) (CH.sub.2).sub.n, wherein n represents an integer from 1 to 12; c) (CH.sub.2CH.sub.2Y).sub.n, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; d) CH.sub.2(CH.sub.2CH.sub.2Y).sub.nCH.sub.2, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; e) (CH.sub.2CH.sub.2NR).sub.n, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; f) CH.sub.2(CH.sub.2CH.sub.2NR).sub.nCH.sub.2, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; R.sup.2, R.sup.3 can be the same or different and represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; and R.sup.4 and R.sup.5 can be the same or different, and each R.sup.4 and R.sup.5 independently represents an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms.

2. The styrene derivative of claim 1, which is of Formula (Ia) or (Ib) ##STR00009##

3. The styrene derivative of claim 1, wherein R.sup.1 is selected from the group consisting of: a) a single bond; and b) (CH.sub.2).sub.n, wherein n represents an integer from 1 to 12, preferably wherein n is 1 or 2, in particular wherein n is 1.

4. The styrene derivative of claim 3, wherein R.sup.1 is (CH.sub.2).sub.n, wherein n represents an integer from 1 to 5, preferably wherein n represents an integer from 1 to 3, in particular wherein n is 1.

5. The styrene derivative of claim 1, wherein R.sup.2 and R.sup.3 can be the same or different and represent CH.sub.3 or C.sub.6H.sub.5, preferably wherein R.sup.2 and R.sup.3 represent CH.sub.3.

6. The styrene derivative of claim 1, wherein R.sup.4 and R.sup.5 all represent CH.sub.3, preferably wherein the styrene derivative is of Formula (1), (2), (3), (4), (5), or (6) ##STR00010## more preferably wherein the styrene derivative of Formula (I) is selected from any one of formulae (1), (2), (4), and (5); most preferably wherein the styrene derivative of Formula (I) is selected from any one of formulae (4) and (5).

7. A method for the preparation of a styrene derivative of Formula (I) ##STR00011## wherein R.sup.1 is selected from the group consisting of: a) a single bond; b) (CH.sub.2).sub.n, wherein n represents an integer from 1 to 12; c) (CH.sub.2CH.sub.2Y).sub.n, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; d) CH.sub.2(CH.sub.2CH.sub.2Y).sub.nCH.sub.2, wherein n represents an integer from 1 to 12, and Y can independently be oxygen or sulfur; e) (CH.sub.2CH.sub.2NR).sub.n, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; f) CH.sub.2(CH.sub.2CH.sub.2NR).sub.nCH.sub.2, wherein n represents an integer from 1 to 12, and R can independently represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; R.sup.2, R.sup.3 can be the same or different and represent an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; and R.sup.4 and R.sup.5 can be the same or different, and each R.sup.4 and R.sup.5 independently represents an alkyl group containing from 1 to 10 carbon atoms, or an aryl or aralkyl group containing from 6 to 10 carbon atoms; wherein a halogenosilane of Formula (II) ##STR00012## wherein X.sup.1 is selected from chlorine, bromine, and iodine atoms, and R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are as defined above, is reacted with a magnesium compound of Formula (III), ##STR00013## wherein X.sup.2 is selected from chlorine, bromine, and iodine atoms, and R.sup.1 is as defined above.

8. The method of claim 7, wherein the reaction is performed in an organic solvent in an inert gas atmosphere, preferably wherein the reaction is performed in an aliphatic or cyclic ether solvent, in particular wherein the solvent is tetrahydrofuran (THF).

9. Use of the styrene derivative of claim 1, in the preparation of a copolymer thereof.

10. The use of claim 9, wherein the copolymer comprises repeat units that are derived from A) 20 wt. % to 99.95 wt. %, by weight of the copolymer, of one or more diene monomers; B) 0 wt. % to 60 wt. %, by weight of the copolymer, of one or more vinyl aromatic monomers; and C) 0.05 wt. % to 50 wt. %, by weight of the copolymer, of one or more styrene derivatives of Formula (I) ##STR00014##

11. The use of claim 9, wherein an alkali metal salt derivative of the styrene derivative of Formula (I) is used as initiator for the copolymerization of i) one or more conjugated diene monomers and optionally ii) one or more vinyl aromatic monomers, wherein the alkali metal is selected from lithium, sodium, and potassium.

Description

EXAMPLES

Example 1

[0061] A reactor of 2 L capacity, equipped with a magnetic stirrer, a dropping funnel and a gas introduction attachment with an oil valve (Zaitsev washer), was loaded in nitrogen atmosphere with magnesium metal (14.0 g, 0.58 mole), followed by addition of dry and deoxygenated tetrahydrofuran (THF, 890 mL) and I.sub.2 (0.73 g, 2.9 mmole). The mixture obtained was refluxed until change of the color from brown to pale-yellow, then it was cooled down to 25 C. Next, N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (ClMe.sub.2SiN(SiMe.sub.3).sub.2) (140.00 g, 0.55 mole) and the remaining part (280 mL) of the solvent were added to such a prepared activated magnesium. The syringe placed in a syringe pump was filled with 4-vinylbenzyl chloride (para-VBC) (85.92 g, 0.56 mole). VBC was added dropwise into the mixture for 10 hours, at 25 C. After the dosing of VBC was completed, the reactor temperature was maintained in the range of 40 C. for one hour, followed by cooling to room temperature. Then the solvent was evaporated from the post-reaction mixture under reduced pressure and 1.00 L of hexane (mixture of isomers) was added to the residue. The obtained suspension was filtered off and the precipitate was washed with three portions of hexane of 200 mL each. Then the solvent was evaporated from the obtained filtrate under reduced pressure, followed by drying in a vacuum at 40 C. until a constant pressure was achieved. 165.00 g of N-(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine were obtained with the yield of 89%. The product was subjected to spectroscopic analysis.

Example 2

[0062] A reactor of 2 L capacity, equipped with a magnetic stirrer, a dropping funnel and a gas introduction attachment with an oil valve (Zaitsev washer), was loaded in nitrogen atmosphere with magnesium metal (14.0 g, 0.58 mole), followed by addition of dry and deoxygenated tetrahydrofuran (THF, 890 mL) and 1,2-dibromoethane (1.1 g, 5.8 mmole). The mixture obtained was refluxed until ethylene evolution completes, then it was cooled down to 25 C. Next, N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (ClMe.sub.2SiN(SiMe.sub.3).sub.2) (140.00 g, 0.55 mole) and the remaining part (280 mL) of the solvent were added to such a prepared activated magnesium. The syringe placed in a syringe pump was filled with 4-vinylbenzyl chloride (para-VBC) (85.92 g, 0.56 mole). The para-VBC was added dropwise into the mixture for 10 hours, at 25 C. After the dosing of VBC was completed, the reactor temperature was maintained in the range of 40 C. for one hour, followed by cooling to room temperature. Then the solvent was evaporated from the post-reaction mixture under reduced pressure and 1.00 L of hexane (mixture of isomers) was added to the residue. The obtained suspension was filtered off and the precipitate was washed with three portions of hexane of 200 mL each. Then the solvent was evaporated from the obtained filtrate under reduced pressure, followed by drying in a vacuum at 40 C. until a constant pressure was achieved. 161.50 g of N-(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine were obtained with the yield of 87%. The product was subjected to spectroscopic analysis.

Example 3

[0063] Acting in the same manner as in Example 1, N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (ClMe.sub.2SiN(SiMe.sub.3).sub.2) (140.00 g, 0.55 mole) was reacted with vinylbenzyl chloride VBC (mixture of 43% para- and 57% of meta-isomer) (85.92 g, 0.56 mole) in the presence of magnesium metal (14.0 g, 0.58 mole) activated with I.sub.2 (0.73 g, 2.9 mmole). 165 g of N(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine was obtained with the yield of 89%. The product was subjected to spectroscopic analysis.

Example 4

[0064] A reactor of 2 L capacity, equipped with a magnetic stirrer, a dropping funnel and a gas introduction attachment with an oil valve (Zaitsev washer), was loaded in nitrogen atmosphere with magnesium metal (14.0 g, 0.58 mole), followed by addition of dry and deoxygenated tetrahydrofuran (THF, 890 mL) and DIBAH((i-Bu).sub.2A1H), 0.8 g, 5.62 mmole). This was followed by stirring of the reactor contents at 25 C. The activation of magnesium was conducted until hydrogen evolution completes. Then N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (140.00 g, 0.55 mole) and the remaining part (280 mL) of the solvent were added to such a prepared activated magnesium. The syringe placed in a syringe pump was filled with vinylbenzyl chloride VBC (mixture of 43% para- and 57% of meta-isomer) (85.92 g, 0.56 mole). VBC was added dropwise into the mixture for 10 hours, at 25 C. After the dosing of VBC was completed, the reactor temperature was maintained in the range of 40 C. for one hour, followed by cooling to room temperature. Then the solvent was evaporated from the post-reaction mixture under reduced pressure and 1.00 L of hexane (mixture of isomers) was added to the residue. The obtained suspension was filtered off and the precipitate was washed with three portions of hexane of 200 mL each. Then the solvent was evaporated from the obtained filtrate under reduced pressure, followed by drying in a vacuum at 40 C. until a constant pressure was achieved. 180.00 g of N-(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine were obtained with the yield of 97%. The product was subjected to spectroscopic analysis.

Example 5

[0065] A jacketed reactor of 500 L capacity, equipped with a paddle stirrer, a metering system with piston pump and a reflux condenser equipped with a gas introduction attachment, was loaded in nitrogen atmosphere with magnesium metal (3.89 kg, 0.16 kmole), followed by addition of dry and deoxygenated tetrahydrofuran (THF, 247.00 L) and DIBAH ((i-Bu).sub.2AlH, 0.22 kg, 1.56 mole). This was followed by stirring of the reactor contents at 25 C. The activation of magnesium was conducted until hydrogen evolution completes (ca. 15 min). Then, N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (ClMe.sub.2SiN(SiMe.sub.3).sub.2) (38.90 kg, 0.15 kmole) and the remaining part (78.00 L) of the solvent were added to such a prepared activated magnesium. Then, dozing of VBC (mixture of 43% para- and 57% of meta-isomer, 23.9 kg, 0.16 kmole), was started and was continued for 10 hours at 25 C. After the dosing of vinylbenzyl chloride was completed, the reactor temperature was maintained at about 40 C. for one hour, followed by cooling to room temperature. Then the solvent was evaporated from the post-reaction mixture under reduced pressure and 277.00 L of hexane was added to the residue. The obtained suspension was filtered off in a Nutsche filter and the precipitate was washed with three 55 L portions of hexane. Then the solvent was evaporated from the obtained filtrate under reduced pressure, followed by drying in a vacuum at 40 C. until a constant pressure was achieved. 50 kg of N(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine were obtained with a yield of 97%.

Example 6

[0066] A reactor of 1 L capacity, equipped with a magnetic stirrer, a dropping funnel and a gas introduction attachment with an oil valve (Zaitsev washer), was loaded in nitrogen atmosphere with magnesium metal (3.5 g, 0.145 mole), followed by addition of dry and deoxygenated tetrahydrofuran (THF, 200 mL) and DIBAH((i-Bu).sub.2A1H), 0.2 g, 1.405 mmole). This was followed by stirring of the reactor contents at 25 C. The activation of magnesium was conducted until hydrogen evolution completes. Then, N-(chlorodimethylsilyl)-N,N-bis(trimethylsilyl)amine (35.00 g, 0.137 mole) and the remaining part (70 mL) of the solvent were added to such a prepared activated magnesium. The syringe placed in a syringe pump was filled with 4-bromostyrene (25.6 g, 0.14 mole). The 4-bromostyrene was added dropwise into the mixture for 10 hours, at 25 C. After the dosing of VBC was completed, the reactor temperature was maintained in the range of 40 C. for one hour, followed by cooling to room temperature. Then the solvent was evaporated from the post-reaction mixture under reduced pressure and 0.25 L of hexane (mixture of isomers) was added to the residue. The obtained suspension was filtered off and the precipitate was washed with three portions of hexane of 50 mL each. Then, the solvent was evaporated from the obtained filtrate under reduced pressure, followed by drying in a vacuum at room temperature, until a constant pressure was achieved. The GCMS analysis of the residue revealed 28% yield of the desired product, (N-(dimethyl(4-vinylphenyl)silyl)-N,N-bis(trimethylsilyl)amine.

[0067] Products 1 to 6 were analyzed using: [0068] .sup.1H, and .sup.13C, .sup.29Si NMR spectra, recorded with the use of NMR spectrometers of the types Bruker Ultra Shield 400 MHz, [0069] GC-MS mass spectrometers of the types Bruker MS320 and GC-MS Varian Saturn 2000.

[0070] Shown in Table 1 are data obtained by NMR spectroscopy or GCMS analysis.

[0071] In order to provide more details about the synthesis and properties of elastomers prepared in accordance with the teaching of the present invention, functionalized styrene-butadiene copolymers with exactly controlled micro- and macrostructure and with functional groups of various types are described in Examples A2 to A4 below, and are compared with a non-functionalized copolymer as described in Comparative Example A1. Parts per hundred rubber, phr, and % are based on mass unless otherwise specified. The measurement methods and evaluation methods of properties are shown further below.

TABLE-US-00001 TABLE 1 Characterization of the compounds obtained in the Examples. Ex. NMR analysis or MS data 1, 2 .sup.1H NMR (400 MHz, CDCl.sub.3, 300 K) (ppm) = 7.26 (d, .sup.3J.sub.H-H = 8.0 Hz, 2H, C.sub.6H.sub.4); 6.99 (d, .sup.3J.sub.H-H = 8.0 Hz, 2H, C.sub.6H.sub.4); 6.67 (dd, 1H, CH) ; 5.66 (dd, 1H, CH.sub.2) ; 5.13 (dd, 1H, CH.sub.2) ; 2.22 (s, 2H, CH.sub.2) , 0.19 (s, 18H, N(SiMe.sub.3).sub.2); 0.15 (s, 6H, SiMe.sub.2). .sup.13C NMR (100.63 MHz, CDCl.sub.3, 300 K) (ppm) = 140.44; 137.08; 133.73; 128.80; 126.22; 112.17; 30.69; 5.87; 3.64. .sup.29Si NMR (79.49 MHz, CDCl.sub.3, 300 K) (ppm) = 2.96 (N(SiMe.sub.3).sub.2); 1.54 (SiMe.sub.2). 3, para-isomer 4, 5 .sup.1H NMR (400 MHz, CDCl.sub.3, 300 K) (ppm) = 7.26 (d, .sup.3J.sub.H-H = 8.0 Hz, 2H, C.sub.6H.sub.4); 6.99 (d, .sup.3J.sub.H-H = 8.0 Hz, 2H, C.sub.6H.sub.4); 6.67 (dd, 1H, CH); 5.66 (dd, 1H, CH.sub.2); 5.13 (dd, 1H, CH.sub.2); 2.22 (s, 2H, CH.sub.2), 0.19 (s, 18H, N(SiMe.sub.3).sub.2); 0.15 (s, 6H, SiMe.sub.2). .sup.13C NMR (100.63 MHz, CDCl.sub.3, 300 K) (ppm) = 140.44; 137.08; 133.73; 128.80; 126.22; 112.17; 30.69; 5.87; 3.64. .sup.29Si NMR (79.49 MHz, CDCl.sub.3, 300 K) (ppm) = 2.95 (N(SiMe.sub.3).sub.2); 1.54 (SiMe.sub.2). meta-isomer .sup.1H NMR (400 MHz, CDC1.sub.3, 300 K) (ppm) = 7.13 (m, 2H, C.sub.6H.sub.4); 7.06 (bs, 1H, C.sub.6H.sub.4); 6.92 (d, 1H, C.sub.6H.sub.4); 6.66 (dd, 1H, CH); 5.70 (dd, 1H, CH.sub.2); 5.19 (dd, 1H, CH.sub.2); 2.20 (s, 2H, CH.sub.2), 0.17 (s, 18H, N(SiMe.sub.3).sub.2); 0.14 (s, 6H, SiMe.sub.2). .sup.13C NMR (100.63 MHz, CDCl.sub.3, 300 K) (ppm) = 140.68; 137.43; 128.41; 128.34; 126.62; 122.25; 113.43; 30.66; 5.86; 3.72. .sup.29Si NMR (79.49 MHz, CDCl.sub.3, 300 K) (ppm) = 2.98 (N(SiMe.sub.3).sub.2); 1.46 (SiMe.sub.2). 6 MS (EI, 75 eV) m/z(%) = 307.8(16.4); 306.8 (30.7)(M-15); 305.8(100); 289.8(10.6); 263.8(21.4); 236.8(10.1); 235.8(30.1); 219.9(11.8); 218.8(15.1); 217.9(45.1); 161.0(14.0); 147.0(10.2); 146.1(12.8); 145.0(10.3); 132.0(13.5); 130.1(16.7); 73.1(25.6).

Polymerization

Inertization Step:

[0072] Cyclohexane (1,200 g) was added to a nitrogen-purged two liter reactor and treated with 1 gram of 1.6 M n-butyl lithium solution in cyclohexane. The solution was heated to 70 C. and vigorously stirred for 10 minutes to perform cleaning and inertization of the reactor. After that, solvent was removed via a drain valve and nitrogen was purged again.

Example A1 (Comparative)

[0073] Cyclohexane (820 g) was added to the inerted two liter reactor, followed by addition of styrene (31 g) and of 1,3-butadiene (117 g). Inhibitor from styrene and 1,3-butadiene was removed. Next, tetramethylethylenediamine (TMEDA, 2.21 mmol) was added, to provide random incorporation of styrene monomer and to increase the vinyl content of the butadiene units. The solution inside the reactor was heated to 60 C. and continuously stirred during the whole process. When the desired temperature was reached, n-butyl lithium (0.045 mmol) was added to perform quenching of residual impurities. Then, n-butyl lithium (0.845 mmol) was added to initiate the polymerization process. The reaction was carried out as a isothermic process for 60 minutes. After this time, silicon tetrachloride (5.2510.sup.5 mol) was added to the polymer solution as a coupling agent. Coupling was performed for 5 minutes. The reaction solution was terminated using nitrogen-purged isopropyl alcohol (1 mmol) and rapidly stabilized by addition of 2-methyl-4,6-bis(octylsulfanylmethyl)phenol (at 1.0 phr polymer). The polymer solution was treated with isopropanol, and precipitation of polymer occurred. The final product was dried overnight in a vacuum oven.

Example A2 (Styrene Derivate as Comonomer)

[0074] Cyclohexane (820 g) was added to the inerted two liter reactor, followed by addition of styrene (31 g), N(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine 50/50 by weight mixture of isomers of formula (4) and (5) (0.6 g) and 1,3-butadiene (117 g). Inhibitor from styrene and 1,3-butadiene was removed. Next, 2,2-Bis(2-tetrahydrofuryl)propane (DTHFP, 2.52 mmol) was added, to provide random incorporation of styrene monomer and to increase the vinyl content of the butadiene units. The solution inside the reactor was heated to 60 C. and continuously stirred during the whole process. When the desired temperature was reached, n-butyl lithium (0.045 mmol) was added to perform quenching of residual impurities. Then, n-butyl lithium (0.84 mmol) was added to initiate the polymerization process. The reaction was carried out as a isothermic process for 60 minutes. After this time, silicon tetrachloride (6.3010.sup.5 mol) was added to the polymer solution as a coupling agent. Coupling was performed for 5 minutes. The reaction solution was terminated using of nitrogen-purged isopropyl alcohol (1 mmol) and rapidly stabilized by addition of 2-methyl-4,6-bis(octylsulfanylmethyl)phenol (at 1.0 phr polymer). The polymer solution was treated with isopropanol, and precipitation of polymer occurred. The final product was dried overnight in a vacuum oven.

Example A3 (Styrene Derivates as Both Initiator Component and as Comonomer)

[0075] Cyclohexane (820 g) was added to the inerted two liter reactor, followed by addition of styrene (31 g), N-(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine 50/50 by weight mixture of isomers of formula (4) and (5) (0.6 g) and 1,3-butadiene (117 g). Inhibitor from styrene and 1,3-butadiene was removed. Next, 2,2-Bis(2-tetrahydrofuryl)propane (DTHFP, 3.69 mmol) was added as a styrene randomizer and to increase the vinyl content of the butadiene monomercontributed units. The solution inside the reactor was heated to 60 C. and continuously stirred during the whole process. When the temperature was reached, n-butyl lithium (0.045 mmol) was added to the reactor, to perform quenching of residual impurities.

[0076] n-BuLi (1.23 mmol) and N-(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine 50/50 by weight mixture of isomers of formula (4) and (5) (0.4 g) were mixed together in a burette, the contact time was about 15 min, and then the mixture was added to initiate the polymerization process. The reaction was carried out over 60 minutes, as an isothermic process. After this time, silicon tetrachloride (6.3010.sup.5 mol) was added to the polymer solution as a coupling agent. Coupling was performed for 5 minutes. The reaction solution was terminated using nitrogen-purged isopropyl alcohol (1 mmol) and rapidly stabilized by addition of 2-methyl-4,6-bis(octylsulfanylmethyl)phenol (at 1.0 phr polymer). The polymer solution was treated with isopropanol, and precipitation of polymer occurred. The final product was dried overnight in a vacuum oven.

Example A4 (Continuous Polymerization)

[0077] The butadiene-styrene copolymer was prepared in a continuous reactor chain of three reactors having a volume of 10 L (reactor 1), 20 L (reactor 20) and 10 L (reactor 3), respectively, where each reactor was equipped with a paddle stirrer. The agitation speed was 150-200 rpm and filling factor at the level of 50%-60%. Hexane, styrene, 1,3-butadiene, 1,2-butadiene (gel formation prevention additive), DTHFP and N(dimethyl(vinylbenzyl)silyl)-N,N-bis(trimethylsilyl)amine 50/50 by weight mixture of isomers of formula (4) and (5) (the last three reactants as a solutions in hexane) were dosed into the first reactor, with flow rates of 10752.00 g/h, 398.00 g/h, 1499.00 g/h, 19.00 g/h, 102 g/h and 48.00 g/h, respectively. n-Butyl lithium flow rate (n-BuLi, as a solution in hexane) was 107.00 g/h, and N-(dimethyl(vinylbenzyl)silyl)N,N-bis(trimethylsilyl)amine (as a solution in hexane) flow rate was 105.00 g/h. Streams of n-BuLi and 50/50 by weight mixture of isomers of silanamine of formula (4) and (5) were mixed together in the pipe, before entering the reactor, and the contact time was about 15 min. The temperature in the reactors was between 70 C. to 85 C. To obtain branched rubber silicon tetrachloride was added at the reactor 3 inlet, at the entry of static mixer, in a SiCl.sub.4/active n-BuLi ratio 0.05. The coupling reaction was performed at 70-85 C. At the reactor 3 outlet, 2-methyl-4,6-bis(octylsulfanylmethyl)phenol (as a solution in hexane) was added as an antioxidant (142 g/h). The polymers were recovered by a conventional recovery operation using steam stripping of the solvent, were dried in a screw-type dewatering system at 70 C., and then dried for 40 minutes in the dryer.

Characterization of Samples A1 to A4

Vinyl Content (%)

[0078] Determined by 600 MHz .sup.1H-NMR, based on BS ISO 21561:2005

Bound Styrene Content (%)

[0079] Determined by 600 MHz .sup.1H-NMR, based on BS ISO 21561:2005

Molecular Weight Determination

[0080] Gel Permeation Chromatography was Performed Via PSS Polymer Standards Service multiple columns (with guard column) using THF as the eluent and for sample preparation. Multiangle laser light scattering measurements were carried out using a Wyatt Technologies Dawn Heleos II light scattering detector, DAD (PDA) Agilent 1260 Infinity UV-VIS detector and Agilent 1260 Infinity refractive index detector.

Glass Transition Temperature ( C.)

[0081] Determined based on PN-EN ISO 11357-1:2009

Mooney Viscosity (ML (1+4)/100 C.)

[0082] Determined based on ASTM D 1646-07, using an large rotor under the conditions of preheating=1 minute, rotor operating time=4 minutes, and temperature=100 C.

Vulcanization Characteristics

[0083] Determined based on ASTM D6204, using RPA 2000 Alpha Technologies rubber processing analyzer, operating time=30 minutes, and temperature=170 C.

Evaluation and Measurement of Properties of Rubber Composition

[0084] A vulcanized rubber compound was prepared using a polymer obtained in each of Examples A1 to A4, and was measured for the following test parameters [0085] i) Tire predictors (tan at 60 C., tan at 0 C., tan at 10 C.) [0086] A vulcanized rubber compound was used as a test sample and measured for this parameter, using a dynamic mechanical analyzer (DMA 450+ MetraviB) in single shear mode under the conditions of dynamic strain=2%, frequency=10 Hz, in the temperature range of from 70 to 70 C., with a heating rate of 2.5 K/min. [0087] ii) Rebound resilience [0088] Determined based on ISO 4662

[0089] Table A1 shows the characterization results for the four samples synthesized for this study.

TABLE-US-00002 TABLE A1 Sty- Vinyl rene con- con- Exam- M.sub.n M.sub.w M.sub.w/ tent tent Tg ple [g/mol] [g/mol] M.sub.n [%].sup.1 [%] Mooney [ C.] A1 223,000 323,000 1.44 61.90 20.45 60.4 26.8 (comp.) A2 225,000 319,500 1.42 61.82 20.90 55.4 24.3 A3 226,000 329,900 1.46 62.70 21.36 60.2 25.1 A4 184,000 260,900 1.76 62.53 21.58 52.1 23.5 .sup.1Based on 1,3-butadiene content

Compounding

[0090] Using the rubbers obtained in Examples A2, A3, A4 and Comparative Example A1, respectively, compounding was made according to the compounding recipe of rubber composition shown in Table A2. The compounding of the solution styrene-butadiene rubber, fillers, and rubber additives was performed in a Banbury type of internal mixer (350E Brabender GmbH& Co. KG) and on a lab sized two roll mill. The rubber compounds were mixed in two different stages and the final pass was completed on a two roll mill. The first stage was used to mix the polymer with oil, silica, silane coupling agent, 6PPD and activators in several steps. The second stage was to further improve the distribution of the silica along with adding of carbon black, then the compound was allowed to sit for 24 hours. In order to be conditioned for the final pass, the rubber compound was allowed to condition for four hours. The final mixing was performed on a two roll mill. The last step was used to add the cure packages. Then, each compound was vulcanized at 170 C., for T.sub.95+1.5 minutes (based on RPA results), to obtain vulcanizates. Each vulcanized rubber compound was evaluated and measured for the above-mentioned curing characteristics, tire predictors and rebound resilience. The results are shown in Table A3.

TABLE-US-00003 TABLE A2 Component phr SBR 75 Polybutadiene rubber.sup.1 25 Silica.sup.2 80 Carbon Black.sup.3 10 Stearic acid 2 Zinc oxide 3 Oil extender.sup.4 37.5 6PPD.sup.5 2 Bis[3-(triethoxysilyl)propyl]tetrasulfide.sup.6 6.4 N-tert-butyl-2-benzothiazole sulfenamide.sup.7 1.7 1,3-Diphenylguanidine.sup.8 2 Sulphur 1.5 .sup.1Synteca 44, a product of Synthos .sup.2Zeosil 1165MP, a product of Solvay .sup.3ISAF-N234, a product of Cabot corporation .sup.4VivaTec 500, a product of Klaus Dahleke KG .sup.5VULKANOX 4020/LG, a product of Lanxess .sup.6Si 69, a product of Evonik .sup.7LUVOMAXX TBBS, a product of Lehmann & Voss & Co. KG .sup.8DENAX, a product of Draslovka a.s.

TABLE-US-00004 TABLE A3 Rebound Rebound resilience resilience tan tan , tan , Example (23 C.), [%] (70 C.), [%] (60 C.) (0 C.) (10 C.) A1 (comp.) 31.0 56.0 0.182 0.5082 0.6540 A2 34.0 62.0 0.142 0.6455 0.7446 A3 37.0 67.0 0.132 0.6567 0.7796 A4 37.0 66.0 0.144 0.6690 0.9228

[0091] It is apparent from these results that in a silica mix, as judged based on the properties in the vulcanized state, SSBR A3 in accordance with the teaching of the invention imparts to the corresponding rubber composition A3 reinforcement properties which are superior to those obtained with the control SSBR A1 and with the other SSBR A2 in accordance with the teaching of the invention. Moreover, the data in Table A3 shows that SSBR A4 obtained in continuous polymerization has better reinforcement properties compared to control SSBR A1 and to SSBR A2.

[0092] Furthermore, the tire predictors of rubber composition A3 in accordance with the teaching of the invention are improved relative to those of the control rubber composition A1 and of the rubber compositions A2 and A4 (in terms of rolling resistance) in accordance with the teaching of the invention. Moreover, said tire predictors are improved for rubber composition A2 in accordance with the teaching of the invention relative to the control rubber composition A1. Furthermore tire predictors are improved for rubber composition A4 in accordance with the teaching of the invention relative to the control rubber composition A1 additionally ice traction and dry traction properties are improved relative to those of the rubber composition A1, A2 and A3.

[0093] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in this art that various changes and modifications can be made therein without departing from the scope of the subject invention, which scope is defined by the following claims.