RU2502754C2 - Rubber mixture - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: rubber mixture contains the following, pts.wt: soluble butadiene-styrene rubber with addition of TDAE oil with low content of polycyclic aromatic hydrocarbons 90-100, rubber with a cis-butadiene linear structure with high content of cis-links on a neodymium catalyst 10-20, natural rubber 5-8, insoluble sulphur 2-3, vulcanising group 3-8, silica filler with specific surface area of 165 m²/g 70-80, microcrystalline wax-based stabiliser 1-2, antiaging agents 3-5, process additive 1-3, binding agent - bis[3-(triethoxy)-silylpropyl]-tetrasulphide 10-15.

EFFECT: improved adhesion on a wet road with lower rolling loss and obtaining fuel-efficient tyres.

1 dwg, 3 tbl

Description

The invention relates to a rubber mixture based on a combination of a solution of styrene-butadiene rubber, cis-butadiene rubber on a neodymium catalyst and a small fraction of natural rubber containing silicic acid filler, which can be used in the tire industry to develop rubber formulations for treads of summer and all-season tires with road tires patterned.

A technical solution is known (patent RU 2129131 priority date 11/08/1995), providing for the use of unsaturated rubbers rubber compound for winter tires, including butadiene rubber, but the technical solution is the closest to the invention in technical essence (patent RU 2308469 priority date January 24, 2006), which provides for the use of low-hysteresis fuel-efficient tires with improved grip properties for the tread. In rubber mixtures of the indicated type, emulsion (BSK) or solution (DSS) styrene-butadiene rubbers or their mixtures with other polydienes are used as the main polymer, and modern brands of precipitated silicic acid fillers (OKN) are used as a reinforcing agent, providing hydrophobization of hydrophilic particles of OKN in the hydrophobic matrix of rubber and its dispersion, silane coupling agents are used, mainly bis- [3- (triethoxy) silylpropyl] tetrasulfide (TESPT). However, this known technical solution does not have sufficient high grip properties of the tread with a wet coating and low-hysteresis losses at 60 ° C of tread rubber of summer and all-season tires.

The advantage of tread rubber mixtures based on a combination of a solution of styrene-butadiene and synthetic cis-butadiene rubber when filled with silicic acid filler is increased wear resistance, low rolling resistance, high wet grip, which is one of the main positive factors for summer tread rubber. Based on the priority requirements for the output characteristics of tires, the requirements for rubbers and materials, as well as for mixing and profiling, have changed. The most relevant are: uniformity of rubber compounds, better processability, durability of tires, as well as environmental friendliness at the stage of production and operation of tires. (Pichugin A.M. // Material science aspects of creating tire rubbers. Scientific publication - Moscow, 2008).

The objective of the invention is to obtain a rubber compound for the tread of summer tires, providing better traction on wet roads with lower rolling losses and obtaining fuel-efficient tires.

To solve this problem, a rubber mixture based on a combination of a solution of styrene-butadiene rubber with an increased styrene content of up to 25% and 50% of the mass fraction of 1,2 units per butadiene part of the chain, with the addition of 27% TDAE (treated distillated aromatic extract) oil was developed low in polycyclic aromatic hydrocarbons, synthetic rubber of cis - butadiene linear structure, high in 1.4 cis units (96-98%) on a neodymium catalyst and natural rubber of the brand STR, including a wax stabilizer m crocrystalline, technological additive, antioxidants based on N- (1,3-dimethylbutyl) -N'-phenyl-n-phenylenediamine and a mixture of N, N'-diaryl-n-phenylenediamines, polymerized 2,2,4-trimethyl-1, 2-dihydroquinoline, insoluble sulfur (80% insoluble sulfur and 20% mineral oil), a vulcanizing group, a bis- [3- (triethoxy) silylpropyl] -tetrasulfide coupling agent and a dosage of silica filler with a specific surface area of 165 m ² / g at the following ratio of components:

Styrene butadiene rubber with increased styrene content up to 25% and up to 60% mass fraction of 1,2 units per butadiene part of the chain, with the addition of 27% TDAE brand oil (treated distillated aromatic extract) 90.0 ÷ 100.0 Synthetic rubber cis-butadiene linear structures high in 1.4 cis units (96-98%) on a neodymium catalyst 10.0 ÷ 20.0 Natural rubber brand STR 5.0 ÷ 8.0 Sulfur insoluble (80% insoluble sulfur and 20% mineral oil) 2.0 ÷ 3.0 Vulcanizing group 3.0 ÷ 8.0 Specific silica filler surface 165 m ² / g 70.0 ÷ 80.0 Wax Stabilizer microcrystalline 1,0 ÷ 2,0 Antioxidants 3.0 ÷ 5.0 Technological Additive 1,0 ÷ 3,0 The binding agent is bis- [3- (triethoxy) silylpropyl] tetrasulfide 100 ÷ 150

The developed rubber compounding allows for summer and all-season tires to improve grip, stability and handling at high speeds, reduce rolling resistance and achieve high ride comfort through the use of a combination of styrene butadiene rubber with an increased styrene content of up to 25% and 50% mass fraction of 1,2 units per butadiene part of the chain, with the addition of 27% TDAE oil (treated distillated aromatic extract) and synthetic cis-butadiene rubber, linear structure and high obsession 1,4-cis units (96-98%) of a neodymium catalyst, a small fraction of natural rubber brand STR, as well as the use of silicic acid filler with a specific surface of 165 m ² / g, have the greatest influence on the output properties of rubber tires and operational indicators .

The composition of the rubber compounds are presented in table 2.

The use of a solution of styrene-butadiene rubber with an increased styrene content of up to 25% and 50% of the mass fraction of 1,2 units per butadiene part of the chain, with the addition of 27% TDAE oil (treated distillated aromatic extract) provides strength characteristics to rubber, improves its properties when wet »Traction while reducing rolling losses. Rubbers based on synthetic rubber of cis-butadiene, linear structure and a high content of cis 1,4-units (96-98%) on a neodymium catalyst have the best range of wear resistance properties. The introduction of STR rubber into the rubber mixture allows you to maintain elasticity, increase abrasion and tear resistance. As protection against fatigue properties, exposure to heat and ozone, the following are used: a microcrystalline wax stabilizer and long-acting antioxidants based on N- (1,3-dimethylbutyl) -N'-phenyl-n-phenylenediamine and a mixture of N, N'- diaryl-n-phenylenediamines; polymerized 2,2,4-trimethyl-1,2-dihydroquinoline. As a reinforcing filler, a silica filler with a specific surface of 165 m ² / g is used, which makes it possible to obtain dynamic properties of the material, which cannot be achieved using carbon black. Improved tire properties, such as lower rolling resistance and high grip, are especially important for tread rubber.

Due to the reaction of silicic acid and a binder, the interaction of the filler-filler particles of silicic acid is reduced, and the interaction of silicic acid and non-polar polymer is increased.

Without a bonding agent, silica technology could not work. The choice of the most effective silica filler with a specific surface area of 165 m ² / g in combination with a bis- [3- (triethoxy) -silylpropyl] -tetrasulfide coupling agent, currently improves the dispersion of the rubber compound, improves the physical properties of tires, such as tread life , rolling resistance (which directly affects the fuel economy of a car), wear resistance and wet grip. Rubbers based on it have a high dispersing and reinforcing ability.

The solution of this problem made it possible to obtain positive results of the tire output characteristics at the Idiada training ground for laboratory and road tests of tires of size 235 / 55R17 of model V-237 99H on a Volkswagen Tiguan car, it demonstrates a faster and more spontaneous response to steering, according to braking characteristics when wet coating, acoustic comfort.

The properties of the rubber compounds in comparison are shown in table 1. Received positive estimated results of the output characteristics of the tires in points in comparison with the prototype tire:

- movement in a straight line,

- steering characteristic

- active safety,

- management on a wet road surface,

- mechanical comfort.

The test results are presented in Fig., In table 3.

The rubber mixture is manufactured on new technological equipment in a rubber mixer with interlocking rotors, adjustable gaps between the rotors - the line of master batch and rubber mixer with tangential rotors - the line of the final stages, with additional processing on the rollers. The manufacturing mode involves the double entry of a silica filler with a specific surface of 165 m ² / g and a bis-3- (triethoxy) -silylpropyl) -tetrasulfide binder. The rubber mixer with intermeshing rotors can improve the degree of dispersion of the silicic acid filler in the mass of the rubber mixture.

Thus, the developed rubber mixture meets the requirements of automobile plants for tires and provides an optimal compromise between such tire properties as: controllability, wet grip, rolling resistance, ride comfort, and it is recommended to use a combination of styrene butadiene rubber with rubber increased styrene content up to 25% and up to 60% of the mass fraction of 1,2 units per butadiene part of the chain, with the addition of up to 27% TDAE brand synthetic oil chuka cis butadiene linear structure of high cis-1,4 units (96-98%) of a neodymium catalyst and brand STR natural rubber, a silicic acid as the filler with a specific surface of 165 m ² / g.

Table 1 Properties of rubber compounds The name of indicators 1 option 2, 3 options Properties of unvulcanized mixtures Viscosity, units Mooney 73.0 70.3 Gisterezis e 0.170 0.158 Tg delta at 60 ° C 0.156 0.148 Tests on the MDR-2000 at 151 ° C × 30 min Torque, da.Nm minimum 3.82 3.9 maximum 25.12 26.7 Properties of vulcanizates at 151 ° C × 30 min Conditional stress, MPa - at 300% elongation 9.5 10.3 Conditional tensile strength, MPa 19.7 21.1 Elongation at break,% 490 530 Tear resistance, kN / m 78 83 Heat generation, ° С. T arr. 60 57 Shore A hardness, arb. 23 ° C / 100 ° C 68/63 72/67 Rebound Elasticity,% 23 ° C / 100 ° C 22/42 22/41

table 2 The composition of the rubber compounds Name of material mass parts per mass of polymers prototype 1 var. 2 var. 3 var. Rubbers: Emulsion styrene butadiene rubber 100.0 - - - Styrene butadiene rubber with an increased styrene content of up to 25% and up to 60% of the mass fraction of 1,2 units per butadiene part of the chain, with the addition of up to 27% TDAE oil with a low content of polycyclic aromatic hydrocarbons - 70 ÷ 75 90 one hundred Synthetic rubber cis-butadiene linear structure with a high content of cis 1,4-units (96-98%) on a neodymium catalyst - 15 ÷ 25 10.0 20,0 Natural rubber brand STR - 7 ÷ 10 5,0 8.0 Fillers: Active carbon black 65.0 - - - Silicic acid filler with a specific surface of 165 m ² / g - 60 ÷ 65 70.0 80.0 Technological Additive 1,0 ÷ 3,0 1,0 3.0 Sulfur insoluble (80% sulfur insoluble and 20% mineral oil) 1.9 2 ÷ 3 2.0 3.0 Vulcanizing group: 3.0 8.0 Zinc oxide - 1,0 2,5 N-cyclohexyl-2-benzthiazolylsulfene amide - 1,0 0.8 1,2 N, N-Diphenylguanidine - 2.1 0.5 2.1 Stearic acid - 2 0.7 2.2 Coupling agent bis-3- (triethoxy-silylpropyl) -tetrasulfide - 12.0 10.0 15.0 Antioxidants: 3.0 5,0 Polymerized 2,2,4-trimethyl-1,2-dihydroquinoline 2.0 0.5 0.5 1,0 N-Isopril-N'-Phenyl-n-Phenylenediamine 1,0 - - - N- (1,3-Dimethylbutyl) N'-phenyl-n-phenylenediamine - 2,5 1.8 2,5 A mixture of N, N'-diaryl-n-phenylenediamines - 1,5 0.7 1,5 Microcrystalline Wax Stabilizer - 1,5 1,0 2.0

Table 3 Laboratory Road Test Results The name of indicators Prototype
point Option 1
point 2,3 options
point Straight line 8.0 8.0 8.3 Steering characteristic 8.0 7.9 8.0 Active safety 7.75 7.5 7.83 Wet driving 7.76 7.5 7.84 Mechanical comfort 8.0 7.8 8.3

Claims (1)

A rubber mixture based on combinations of solution styrene-butadiene rubber with the addition of TDAE oil with a low content of polycyclic aromatic hydrocarbons, cis-butadiene rubber with a linear structure and a high content of cis units on a neodymium catalyst and natural rubber, including insoluble sulfur - 80% insoluble sulfur 20% mineral oil, curatives, silicic acid filler with a specific surface of 165 m ² / g, based stabilizer microcrystalline waxes, antioxidants, t hnologicheskuyu additive, coupling agent bis [3- (triethoxy) -sililpropil] -tetrasulfid in the following ratio to the total content of the polymers pbw .:
styrene butadiene rubber with oil low polycyclic TDAE brands aromatic hydrocarbons 90-100 cis-butadiene rubber linear structure and high the content of cis units on a neodymium catalyst 10-20 natural rubber 5-8 insoluble sulfur - 80% insoluble sulfur and 20% mineral oil 2-3 vulcanizing group 3-8 silica filler with a specific surface of 165 m ² / g 70-80 microcrystalline wax stabilizer 1-2 antioxidants 3-5 technological additive 1-3 binding agent - bis- [3- (triethoxy) silylpropyl] - tetrasulfide 10-15

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