BRPI1002041A2 - silically specialized rubber composition containing silica specialized and products with components thereof - Google Patents

Abstract

SPECIALIZED SILICA, RUBBER COMPOSITION CONTAINING SPECIALIZED SILICA AND PRODUCTS WITH SAME COMPONENTS. The invention relates to functionalized ally precipitated silica, to rubber compositions containing that silica, particularly sulfur cured rubber compositions and articles of manufacture with a component therefor, such as tires. The invention relates in particular to synthetic amorphous silica, particularly a precipitated silica, treated with an allyl silane, particularly a precipitated silica containing functional allyl groups.

Description

"SPECIALIZED SILICA, RUBBER COMPOSITION CONTAINING SPECIALIZED SILICA AND PRODUCTS WITH SAME COMPONENTS"

The present depositors claim the benefit of the U.S. Provisional Application; Serial Number 61 / 223,434, filed July 7, 2009.

Field of the Invention

The invention relates to functionalized allyl precipitated silica, rubber compositions containing such silica, particularly sulfur-cured rubber compositions with one component manufacture thereof, such as tires. The invention relates in particular to synthetic amorphous silica, particularly a precipitated silica treated with an allyl silane, particularly to a precipitated silica containing functional allyl groups.

Background of the Invention

Rubber compositions are most often reinforced with reinforcing fillers such as at least one of rubber reinforced carbon black and synthetic amorphous silica (e.g. precipitated silica).

Several products contain at least one compound having such rubber compositions as, for example, tires.

In order to enhance the reinforcing effects of precipitated silica rubber, a coupling agent is typically employed in combination with the precipitated silica.

Such coupling agent typically contains a fraction (e.g., "hydroxy group reactive" with hydroxyl groups (e.g., silanol groups) in the precipitated silica and another different fraction (e.g., polysulfide as a contributing fraction of sulfur, and which interacts with elastomers containing double carbon-carbon bonds (eg diene-based elastomers).

A typical disadvantage of this polysulfide moiety of the desilyl coupling agent is its sulfur contribution at an elevated temperature of the uncured rubber composition, such as during physical mixing of the uncured rubber composition, which interacts with the double carbon bonds. -a-carb of an elastomer in the rubber composition to promote significantly higher viscosity of the rubber composition which leads to greater rubber processing difficulties or challenges. This phenomenon is known to those skilled in the rubber technique.

For the present invention, a precipitated rubber reinforcing silica is used which can be commonly characterized as having properties typical of a synthetic precipitated silica used in reinforcing rubber compositions such as a BET nitrogen surface area in a range of 120 µm. at 300 m2 / g; a CTAB surface area in the range 100 to 300 m2 / g with a BET / CTAB surface area ratio in the range 0.8 to 1.3.

BET nitrogen surface may be determined according to ASTM D1993, or equivalent and CTAB surface area according to DIN 53535.

A significant fact of proposing precipitated silica with the BET / CAB ratio required for rubber reinforcement purposes is exemplified in the patent literature as a large range of, for example, 0.8 to 1.3 with a BET surface area, for example. 120 to 300 m 2 / g and a CTAB surface area of, for example, 100 to 300 m 2 / g. For example, see U.S. Patent Application Serial No. 2008/0293871, U.S. Patent No. 6,013234 and EP Patent Publication No. 0901986.

The DBP absorption value or number can be determined according to DIN53601 or equivalent.

In one embodiment, such precipitated silica may be exemplified, for example, by mercury porosimetry, of, for example, and further as measured by a CARLO-ERBA Porosimeter 2000 or equivalent as a surface area in a range 100 to 240 m2 / g, and maximum pore size distribution over a range of 20 to 75 nm (nanometers).

For the present invention it has been found that a precipitated silica for functionalized allyl rubber reinforcement may be employed as a silica reinforcement for a rubber composition. Such allyl functionalized silica does not contain a polysulfide fraction such that sulfur is not present. available to interact prematurely with elastomers in the rubber composition. When formed, allyl precipitated silica functionalized by, for example, treatment of a precipitated silica with an allyl trialkixixane or allyl halosilane means that an alkoxy silane moiety of the allyl alkoxysilane or halogen halo reacts by for example with hydroxyl groups (e.g. silanol groups) and / or hydrogen groups in the precipitated silica. The silica thus treated contains allyl hydrocarbon groups which may interact with the silica and thereby couple the silica with the diene-based elastomer (elastomer formed by polymerization of diene hydrocarbon-containing monomers) in the presence of sulfur dressing during subsequent vulcanization of the rubber composition.

It is also envisioned that, if desired, a relatively high temperature but beneficial mixture of the functionalized allyl silica with the elastomers can occur without an increase in the viscosity promoted by the present sulfur, the rubber mixture prior to the addition of sulfur and sulfur curing accelerators for the rubber blend. It is further noted that such a higher temperature mixture of the rubber composition provides an opportunity for a more efficient mixing of the rubber composition for a shorter mixing time.

Moreover, the presence of the functional allyl groups on the asylum surface (e.g. precipitated silica) is thought to provide a degree of hydrophobicity to the silica surface to thereby intensify or improve its dispersion within the rubber mixture with consequent intensification or degradation. improves in its reinforcement of the rubber composition.

Representative examples of various allyl silanes for the preparation of functionalized allyl silica are, for example, allyltriethoxy silane, allyltrimethoxysilane, allyl dimethylchlorosilane, allylchlorosilane, allyl methyl dichloro silane, diallyl chloromethyl silane, diallyl dichloro silane and triallchlor silane.

In the description of this invention the term "phr" refers to parts by weight for a material or ingredient per 100 parts by weight of elastomers. The terms "rubber" and "elastomer" are used interchangeably unless otherwise indicated The terms "cu-ra" and "vulcanization" are used interchangeably unless otherwise indicated.

Summary and Practice of the Invention

According to this invention a synthetic (modified) amorphous silica treated with comalyl silane (precipitated silica) is proposed which may be referred to herein as a functionalized allyl precipitated silica.

Such functional allyl precipitated silica is proposed by treatment with amorphous synthetic silica (precipitated silica) with at least one allyl silane.

For the present invention a functionalized allyl precipitated silica is proposed composed of a precipitated silica containing at least one allyl group substituent;

wherein the precipitated silica has:

(A) a surface area of BET nitrogen in the range of 120 to 300 m2 / g

(B) a CTAB surface area in the range 100 to 300 m2 / g, with

(C) a ratio of BET / CTAB surface areas in the range 0.8 to 1.3;

wherein the functionalized allyl precipitated silica is represented by the general formula:

<formula> formula see original document page 4 </formula>

wherein Z represents the precipitated silica; R 2 and R 3 are the same or different radicals composed of an alkyl group containing from 1 to 4 carbon atoms, a cycloalkyl group, a phenyl group, an alkene group containing from 3 to 18 carbon atoms or a cycloalkene radical having from 5 at 8 carbon atoms and R1 is an allyl hydrogen containing hydrocarbon radical. Conveniently, such allyl containing hydrocarbon radical is composed of at least one of:

-CH2-CH = CH2, (allyl hydrocarbon radical)

-CH2-CH = CH-CH3, (2-butene radical)

-CH2-CH = C- (CH3) 2 and (dimethyl-allyl hydrocarbon radical) -CH2-C (CH3) = CH-CH3 (2-methyl-2-butene radical)

where a is an integer in a range from 0 to 2 b is an integer in a range from 0 to 2 and c is an integer in a range from 1 to 3.

In one embodiment, the precipitated silica may have, for example, mercury porosymmetry parameters of:

(A) surface area in the range 100 to 240 m2 / g, and

(B) maximum pore size distribution in the range of 20 to 75 nm.

In practice, such functionalized allyl precipitated silica may be in the form of aggregates of coalescent primary particles with an average aggregate size, for example, in the range of about 0.8 to about 1.2 μ.

According to a further aspect of the invention allyl silane has the general formula (II):

R2a

(II) I

Xd - Si-R1c

R3b

wherein R2 and R3 are the same or different being composed of an alkoxy group having from 1 to 8 carbon atoms a cycloalkoxy group containing from 5 to 8 carbon atoms, and an alkyl group containing from 1 to 4 atoms carbon, a cyclohexyl group, a groupophenyl, an alkene containing from 3 to 18 carbon atoms, or a cycloalkene containing 5 to 8 carbon atoms:

where X is a chlorine atom, a hydroxy or a hydrogen,

wherein R1 is an allyl hydrogen containing hydrocarbon radical; Conveniently the allyl hydrogen containing hydrocarbon radical is composed of at least one of:

-CH2-CH = CH2, (allyl hydrocarbon radical) -CH2-CH = CH-CH3, (2-butene radical) -CH2-CH = C- (CH3) 2 and (dimethyl-allyl hydrocarbon radical) -CH2-C (CH3) = CH-CH3 (2-methyl-2-butene radical)

where a is an integer in a range from 0 to 3, b is an integer in a range from 0 to 3, c is an integer in a range from 1 to 3, and d is an integer in a range from 0 to 3 and a is a, bc, d = 4;

wherein at least one X1 R2 and R3 is present;

where d is = 0, at least one of R2 and R3 is an alkoxy group.

It is intended that for the functionalized allyl precipitated silica R2 and R3 of said allylsilane are the same or different and may be selected from at least one of:

(A) alkoxy group composed of ethoxy or methoxy groups,

(B) cycloalkoxy group, (C) alkyl group composed of methyl, ethyl or propyl groups,

(D) cycloalkyl group,

(E) phenyl group, and

(F) allyl hydrogen containing alkene group. This alkene group is conveniently composed of allyl, 2-butene-dimethylallyl or 2-methyl-2-butane radicals.

Representative examples of such functionalized allyl silane for precipitated asylum functionalization are, for example, allylalkoxy silanes composed of at least one of allyltriethoxy silane, allyltrimethoxysilane and allyl halosylanes composed of at least one of allyl methyl chlorosilane, allyltrichlor -silane, allyl methyl dichloro silane, diallyl chloromethyl silane and diallyl dichlor silane. A desirable functionalized allyl silane is allylchlorosilane.

According to this invention, a rubber composition containing reinforcing charges composed of said functionalized allyl precipitated silica may be provided which may contain at least one rubber-reinforced carbon black and an additional precipitated silica which does not contain allyl functionality. Such rubber composition may further contain at least one silica coupling agent to assist in coupling said precipitated silica to elastomers contained in the rubber composition. In practice, this coupling agent has a reactive moiety with hydroxyl groups in said silica (e.g., silanol groups) and another different moiety interactive with the elastomers contained in said rubber composition.

For example, a rubber composition is proposed which comprises, based on parts by weight per 100 parts by weight of rubber (phr):

(A) 100 phr of at least one elastomer based on conjugated diene;

(B) about 10 to about 120, alternatively about 40 to about 100, of the reinforcement load wherein said reinforcement chamber is composed of:

(1) about 40 to about 100, alternatively about 50 to about 80, phr functionalized allyl precipitated desilyl (allyl silane treated precipitated silica);

(2) from zero to about 60, alternatively from about 3 to about 30, phr of rubber reinforced smoke black, and

(3) optionally up to about 70 phr of precipitated silica (other than functionalized allyl precipitated silica).

While various methods for producing a functionalized allyl precipitated silica during the manufacture of precipitated silica may be considered, a prefigured method relates to the preparation of the precipitated silica for rubber reinforcement purposes based on the methods described in US Patent No. 5,723,529. can understand:

(A) reacting at least two inorganic materials, in the presence of water with a strong base to form an aqueous solution of such a product, wherein the inorganic materials are composed, based on 100 parts by weight, of:

(1) 60 to 99.9 parts of silicon dioxide, and

(2) from 0.1 to 40 parts of at least one additional inorganic material capable of deforming said aqueous solution, the inorganic materials being selected from at least one of:

(a) oxides of aluminum, iron, magnesium, boron, titanium, zirconium, zinc vanadium and niobium,

(b) salts of aluminum, iron, magnesium, boron, titanium, zirconium, zinc, vanadium, and niobium as phosphates, sulphates and halides thereof, and

(c) natural and synthetic aluminum silicates;

(B) treating the aqueous solution by adding a mineral acid for reaction with said product forming a reaction product thereof and reducing the pH of the solution, thereby producing precipitated particles of the reaction product as a precipitate;

(C) optionally stopping said acid addition from step (B) to said aqueous solution allowing the precipitate to mature for a period of time before resuming acid addition, followed by adding more acid to achieving a desired pH to reach the end of the reaction and precipitation of the reaction product;

(D) optionally, after said acid addition of step (b) and / or step (C) is completed, allowing the precipitate to age over a period of time;

(E) filtering at least one electrolyte with an anion in any selected steps (B) 1 (C) and (D) from at least one of carbonate, silicate, aluminate, borate, aluminosilicate, phosphate, sulfate, halide, thianate and zirconate and cation selected from at least one of lithium, sodium, potassium, magnesium and / or calcium;

(G) treating said precipitate with at least one ionic and / or nonionic surfactant, and

(F) adding at least one of the allyl silanes (described above) in or after eta-pas ©, (B |), (D) and (E). Conveniently, therefore, allyl silane is composed of at least one of:

-CH 2 -CH = CH 2, (allyl hydrocarbon) -CH 2 -CH = CH-CH 3, (2-butene)

-CH 2 -CH = C- (CH 3) 2 and (dimethyl allyl hydrocarbon)

-CH2-C (CH3) = CH-CH3 (2-methyl-2-butene)

In practice, said functionalized allyl precipitated silica may be formed by pretreatment of the allyl silane precipitated silica prior to its addition to the rubber composition or may be treated in situ in the rubber composition by adding the precipitated silica and said allyl silane individually. for the rubber composition.

According to a further aspect of this invention, a manufacturing article, such as a tire, with at least one compound component of said rubber composition is proposed; Such a tire component may be, for example, at least one of: tire sidewall, sidewall insert, tire sidewall apex, tarpaulin, metallic lining and lane or tread.

From a historical perspective according to US Patent Nos. 5,708,069,7,550,610 and 5,789,514 useful silica may be derived, for example, by hydrophobicity of a silica hydrogel with, e.g., an organo mercaptosilane and alkyl silane and product drying. The resulting hydrophobicity silica gel may be mixed with natural rubber and synthetic rubber.

A generic description of silica gel and precipitated silica can be seen, for example, in Encvclopedia of Chemical Technology, Fourth Edition (1997), Volume 21, Kirk-Othmer, pages 1020 to 1023.

Although silica gels are a form of precipitated silica, this invention is intended to be a significant tangent thereof in that they have the required surface area characterization BET and CTAB described above in a range of 0.8 to 1.3, instead of significantly different precipitated silicas such as those disclosed in EP0643015 and mentioned in U.S. Patent Application Publication. No. 2008/0293871 as indicated to be of use as an abrasive and / or a thickening component for toothpaste (rather than suitable rubber reinforcements) with a BET surface area of 10 to 130 m2 / g and CTAB surface area of 10 to 70 m2g combined with a BET to CTAB surface area ratio of approximately 1 to 5.2

Rubber compositions are often prepared by blending a diene-based rubber, carbon black and other rubber compounding ingredients, not mentioning sulfur-based rubber dressings in at least one sequential mixing stage. with at least one mechanical mixer normally referred to as a "non-productive" mixing step or stage (s) at elevated temperatures under high shear rubber mixing conditions followed by a final mixing stage or final stage in which Sulfur based sulfur accelerators and sulfur accelerators are added and mixed there at a lower mixing temperature to avoid unnecessary pre-curing of the rubber mixture during the mixing stage. The terms "non-productive" and "productive" blending stages are well known to those skilled in the rubber blending art.

It should be appreciated that the rubber composition is conveniently cooled to a temperature below about 40 ° C between said mixing stages.

Vulcanizable sulfur elastomers may be composed for example of at least one of isoprene and 1,3-butadiene polymers and styrene copolymers of at least one isoprene and 1,3-butadiene.

If desired, at least one of the sulfur vulcanizable elastomers may be composed of:

(A) a coupled elastomer composed of at least one iso-prene and 1,3-butadiene polymer and the styrene copolymer with at least one isoprene and 1,3-butadiene, wherein said coupled elastomer is at least least one silica-tin coupled elastomer, or

(B) a functionalized elastomer of at least one styrene / butadiene (SBR) 1 copolymer elastomer 1,4-polybutadiene elastomer and 1,4-polyisoprene elastomer;

wherein said functionalized elastomers contain functional groups composed of:

(1) reactive amine functional group with said functionalized allyl precipitated silica, or

(2) reactive siloxy functional group with said functionalized allyl precipitated silica rubber reinforcement, or

(3) combining reactive siloxy and amine functional groups with functionalized allyl silica, or

(4) silane / thiol functional group reactive with said functionalized allyl silica, or

(5) hydroxyl functional groups reactive with said functionalized allyl precipitated silica, or

(6) reactive epoxy groups with said functionalized allyl precipitated silica, or

(7) reactive carboxyl groups with said functionalized allyl precipitated silica.

Examples are given below to further illustrate the invention wherein the proportions and percentages of the materials are by weight unless otherwise indicated.

EXAMPLE I

Preparation of functionalized allyl precipitated silica

Precipitated silica (agglomerated synthetic amorphous silica aggregates) were obtained as Zeosil ™ 1165 MP (Micropear I) a Rhodia product.

The precipitated silica in its agglomerate form was placed in a high speed mixer for 3 minutes to fragment (slightly deagglomerate) into a dense formate of precipitated silica aggregates.

Fragmented silica aggregates (deagglomerates) are referred to herein as Silica A.

(A) Treatment with allylchlorosilane

Thirty g of precipitated silica aggregates were placed in a round bottom flask equipped with a Dean-Stark distiller with dry toluene. The silica / toluene suspension was heated and refluxed into the flask and a water / toluene mixture containing about 1.65 ml. of water was collected (removed from the reflux suspension) by azeotropic distillation. The collected (removed) water mixture contained about 5.5 percent by weight of the original silica.

To the remaining silica / toluene mixture, 2.6 g of allylchlorosilane was added dropwise to the reflux suspension in the vial. Upon the addition of allylchlorosilane, the suspension became less viscous and more transparent indicating that a solution was being formed. The solution was stirred under reflux conditions for two hours and then cooled and filtered to give the treated precipitated (allyl functionalized) silica.

The treated treated allyl precipitated silica collected is referred to herein as Silica b.

B - Treatment with allylchlorodimethyl silane

30 g of precipitated silica aggregates were similarly processed using 1.19 g of allylchlorodimethyl silane

The treated and collected functionalized allyl precipitated silica is referred to herein as Silica C.

C - Treatment with allyltriethoxysilane

30 g of precipitated silica aggregates were similarly processed using 1.82 g of allyltriethoxy silane.

The treated and collected functionalized allyl precipitated silica is referred to herein as Silica D.

D - Treatment with N-propyltriethoxy silane (not an allylalkoxy silane

30 g of precipitated silica aggregates were similarly processed using 1.83 g of N-propyltriethoxy silane.

The treated and collected precipitated silica is referred to herein as Silica E.

EXAMPLE II

Evaluation of Pretreated Periclitic Silicas

The treated precipitated silica samples from Example I were evaluated on a rubber composition. The following table A represents the general rubber formulations. Parts and percentages are by weight unless otherwise indicated.

Table A

<table> table see original document page 10 </column> </row> <table> Sulfur 1.5

Sulfur Curing Accelerator, Sulphenamide 2

Zinc Oxide 1.5

Amine-based antioxidant1 0.5

1blubber, SMR20

2Mixture of stearic, palmitic and oleic acids

3Coupling agent composed of bis (3-triethoxypropyl) tetrasulfide with an average of about 3.2 to about 3.8 bonding sulfur atoms on its Evonic Degussa polysulfide bridge as Si69 ™.

4 HAF (High Abrasion Oven) Rubber Reinforcing Carbon Black as N330, an indication of ASTM.

Precipitated silicas of Example I as:

Silica A, untreated aggregates of precipitated silica such as Zeo-sil ™ 1165 MP with a BET nitrogen surface area of about 165 m2 / g. a CTAB surface area of about 160 m2g and therefore with a BET / CTAB ratio of about 1.03.

Silica B, a precipitated silica treated with allylchlorosilane

C1 silica a precipitated silica treated with allylchlorodimethyl silane

Silica D, a precipitated silica treated with allyltriethoxysilane

Silica E1 is a precipitated silica treated with N-propylethyl silane

Samples of rubber compositions prepared by combining the ingredients in an internal rubber mixer using two separate stages or mixing steps, sequences, ie a first non-productive mixing stage (NP) at a relatively high temperature followed by a second productive mixing stage (PR) at a significantly lower mixing temperature where sulfur curing accelerator and zinc oxide were added. This rubber mixing procedure is known to those skilled in the art.

For the non-productive mixing stage (NP) the ingredients are mixed for about 4 minutes until a temperature drop is spontaneously generated via high shear mixing in the internal rubber mixer of about 150 ° C at which time the batch is "precipitated" or removed from the associated internal rubber mixer. The batch is laminated and allowed to cool to below 40 ° C. The batch is then mixed into a productive mixing stage (PR) during which time free sulfur, vulcanization accelerator and zinc oxide are added and mixed for a period of about 2 minutes to a temperature drop of about 110 ° C.

The healing behavior and various cured physical properties of the respective Samples are shown in Table 1 below. For the Cured Rubber Samples the Samples were individually cured for about 30 minutes at a temperature of about 150 ° C.

Rubber samples are identified as Control Rubber Sample 5 Ae Experimental Rubber Samples B. C, D and E.

Table 1

<table> table see original document page 12 </column> </row> <table>

1Rheometer Instrument (MDR)

2Automated Testing System (ATS) Instrument

3Rubber Process Analyzer (RPA)

It can be seen from Table 1 that the values of both 100 and 300 percent modulus were higher for the Rubber B1 C and D Samples using allyl silane treated B1 C and D (functionalized allyl) respectively, when compared to Sample E of Experimental Rubber employing propylsilane treated Silica E.

The energy required to achieve a 300% stretch is also seen higher for Rubber Samples B, C and D using allyl silane (functionalized allyl) treated silicas when compared to Rubber Sample E which employed the Silica Propyltriethoxysilane (non-allyl containing silane) is treated. The energy to achieve a 300 percent stretch is also seen to be greater for Samples B, C and D using allyl silane treated (functionalized allyl) silicas when compared to Rubber Sample E employing propyltriethoxy-treated silica E silane (non-allyl-containing silane). The energy to acquire a 300 percent stretch is considered as a measure of polymeric crosslinking entanglement and polymer / charge interaction. Since the cure and rubber (natural rubber) system is the same for the Rubber Samples, then an increase in energy to achieve a 300 percent stretch is indicative of the increased polymer / charge interaction for the allyl-treated precipitated silicas. silane (functionalized allyl).

The MDR difference between the maximum torque and the minimum torque is seen as smaller for BeD Rubber Samples containing the respective precipitated silica B and silica D treated with allyl silane (functionalized allyl) when compared to the rubber sample. F containing silica F treated with propylalkoxy silane.

The MDR difference between maximum torque and minimum torque is seen as slightly larger for Rubber Sample C containing the respective precipitated Silica C treated with allyl silane (functionalized allyl) compared to Rubber Sample F containing the treated Silica F with propylalkoxy silane.

It is considered that the higher modulus values considered together with the smaller or substantially equivalent maximum and minimum torque differences are still indicative of an increased ratio of rubber / charge interaction for the B1CeD Rubber Samples containing the allyl-treated precipitated silicas. silane (functionalized allyl) when compared to Rubber Sample F containing the treated silica F compropylalkoxy silane.

It is concluded from the present that the allyl groups in the precipitated silicas treated with comalyl silane (functionalized allyl) participate in the sulfur vulcanization process in a method of creating a precipitated silica coupling bridge for rubber.

EXAMPLE III

Evaluation of Precipitated Silica Treated in situ

Precipitated silica (agglomerated synthetic amorphous silica aggregates) was obtained as Zeosil ™ 11165 MP (Micropearl), a Rhodia product. Rubber samples were prepared by combining an allylalkoxy silane and a propyl alkoxy silane (not an allyl silane). separately and individually with the precipitated silica-containing rubber composition.

Thus, the precipitated silica is then treated with allylalkoxy silane or propylalcoxysilane in situ in the rubber composition in an internal rubber mixer.

Rubber samples are referred to herein as Rubber Sample X and Rubber Sample Y.

For Rubber Sample X, allylalkoxy silane was allyltriethoxy silane.

For Rubber Sample prop, propylsilane was N-propyltriethoxysilane

Samples of the rubber compositions were prepared in the manner of Example 1, except for the addition of precipitated silica and allylalkoxy silane, or separate propylalkoxy silane.

Table B below represents the generic rubber formulation. Parts and percentages are by weight unless otherwise indicated.

Table B

Non-Productive Mixing Stage (Ν P) Parts

Cis-1,4-polysoprene natural rubber1 100

Fatty acid 21

Coupling Agent 30

Carbon Black 44

Precipitated silica6 50

Allyltriethoxysilane 3,4

N-propyltriethoxy silane 3.5

Productive Mixing Stage (PR) 1.5

Sulfur 0.5

Sulfur Sulfide Curing Accelerator 2

zinc oxide 1.5

Amine-based antioxidant 0.5

6Silica precipitated as Rhodia's Zeosil ™ 1165 MP

The ingredients were employed in Table A of Example II, except for the precipitated silica in its agglomerated form.

The healing behavior and various cured physical properties of the respective Samples are given in Table 3 below. For the cured Rubber Samples, the A-samples were individually cured for about 30 minutes at a temperature of about 150 ° C. Table 2

<table> table see original document page 15 </column> </row> <table>

It can be seen from Table 2 that both the 100% and 300% modulus values were more accurate for Rubber Sample F using allylalkoxy silane treated silica when compared to Rubber Sample G which employed the in situ treated silica compropylalkoxy silane.

The energy to acquire a 300 percent stretch is top view for Rubber Sample F using allylalkoxy silane in situ treated silica when compared to Rubber Sample G which employed propylsilane in situ treated silica and adifference. between maximum and minimum torque values DR are substantially equivalent. Higher energy to achieve a 300 percent stretch along with the substantially equivalent difference between maximum and minimum torque values is indicative of improved rubber / load interaction for Sample F when compared to the rubber Sample G where it was propylalkoxy silane is used to treat precipitated silica in situ.

The delta tan value is lower for Rubber Sample F where silica was treated in situ with allylalkoxy silane compared to Rubber Sample G where silica was nitrided in situ with propylalkoxy silane. This indicates that the rubber / charge interaction is better for Rubber Sample F than in turn. It is indicative of minor thermal buildup for the rubber composition of Sample F and beneficially lower rolling resistance for a vehicular tire with a tread made of such rubber composition.

It is therefore concluded that the allyl groups in the precipitated silica treated in situ with allylalkoxy silane participate in the sulfur vulcanization process in a way that creates a coupling point for the rubber.

EXAMPLE IV

Additional treated precipitated silicas were prepared in the manner of Example I and herein identified as Silica X and Silica Y.

Silica X contained 3% allyl groups on its surface prepared by treatment of precipitated silica with allyltriethoxysilane.

Silica Y contained 3% propyl groups on its surface prepared by treating the precipitated silica with propyltriethoxysilane.

Rubber compositions were individually prepared with Silica X and Silica Y, respectively, as well as untreated silica identified as Silica Z.

Silica Z is a precipitated silica composed of bis (3-triethoxy-silylpropyl) polysulfide with an average in the range of about 3.4 to about 3.8 sulfur-atoms connecting at their polysulfide bridge as Si69 ™ DA Evonic Degussa .

Table C below represents the general rubber formulation. Parts and percentages are by weight unless otherwise indicated.

Table B

Non-Productive Mixing Stage (Ν P) Parts

Useful 1,4-polybutadiene rubber 70 and 25

Styrene Butadiene Rubber (S-SBR) 80 and 75 Prepared Polymerization Solution

Natural rubber is 1,4-polyisoprene 10 and 100

Naphthenic Rubber Processing Oil 20

Wax (microcrystalline) 1

Fatty Acid 2 2

Coupling agent3 0 and 5.2

Carbon black4 5.2

Silica Z (untreated precipitated silica) 6 0 and 65

Silica X (Allyltriethoxysilane-treated precipitated silica) 0 and 69

Silica Y (precipitated silica treated with N-propyltriethoxysilane) 0 and 69

Productive Mixing Stage (PR)

Sulfur <table> table see original document page 17 </column> </row> <table>

7 1,4-Polybutadiene Rubber as Budene ™ 1207 from The Goodyear Tire & Rubber Company

8 Polymerization in SBR Prepared Solution as Solflex ™ 33H23 from The Goodye-ar Tire & Rubber Company

Rubber Samples H through M were prepared in the manner of Example I.

The healing behavior and the various physical healing properties of the respective Samples are given in Table 3 below. For the cured Rubber Samples, the A-samples were individually cured for about 30 minutes at a temperature of about 150 ° C;

Rubber samples identified as S-SBR Rubber Sample H of

Control and Experimental S-SBR Rubber Samples I and J. Contro-le Natural Rubber is Sample K and LeM Experimental Natural Rubber Samples.

Table 3

<table> table see original document page 17 </column> </row> <table> <table> table see original document page 18 </column> </row> <table>

4 Abrasion time is the time in minutes at a specific elevation in the rheometer torque wrench. For example, in Table TS1 and TS2 are the times for an elevation 1 and 2, respectively, in torque.

It can be seen from Table 3 that the Rubber Sample I containing Silica X (the allylalkoxy silane-treated precipitated silica) has higher modulus values, higher tensile strength and higher energy (300 percent modulus) than Rubber Sample J containing Silica Y (the precipitated silica treated with propylalkoxy silane). This is indicative of the greater rubber / charge interaction due to the presence of allyl groups in the precipitated silica.

It can also be seen from Table 3 that, Sample I has higher modulus values, higher tensile strength and higher energy to achieve 300% stretch than Rubber Sample H. This is considered a surprise here as I visit Sample H to use the silica coupler. This is also indicative of the greater rubble / charge interaction due to the presence of allyl groups in the precipitated silica.

In Table 3 the abrasion times TS1 and TS2 are described for Rubber Samples H through M. It can be seen that JeM Rubber Samples containing propylalkoxy silane treated silica (Silica Y had the highest abrasion times which is an indication of the ability to process the rubber composition without premature curing, or abrasion. It is not considered at present as a surprise factor as the propyl group is not reactive with the elastomer.

It can be seen that Rubber Samples I and L containing the allyl silane-treated (functionalized allyl) precipitated silica (Silica X) had the next longer abrasion times. This is considered an advantage, as Silica X has an ability to bind to the elastomer, and has even longer processing times (up to abrasion) compared to Rubber Samples H and K, which employed conventional coupling with inclusion. of coupling agent.

DRAWING

A drawing is proposed as Figure 1 (FIG 1) to further illustrate the invention as set forth in this Example IV. The drawing is a graph of time in minutes (x-axis) versus torque at a constant temperature of 150 ° C. The torque (y axis) is described as dNm.

IN THE DRAWING

From FIG 1 it is seen that in Control Rubber Sample H using untreated silica, the torque begins to increase immediately. This phenomenon is indicative of the reaction between the coupling agent which became bonded to silica and rubber during mixing of the rubber composition and at an elevated temperature.

This immediate increase in torque is considered unfavorable here for the raw rubber processing plant because it means a rapid increase in the Mooney viscosity of the rubber composition. An increase in rubber viscosity is generally unfavorable for the processing of the rubber composition during its mixing in an internal rubber mixer, as well as its subsequent processing as conformation (eg extrusion) and for proposing resistance to the flow of rubber within a rubber. rubber mold for forming and curing the rubber composition, such as in the manufacture of a rubber tire.

For Experimental Rubber Sample I, the torque remained stable and did not rise significantly for the first 4 minutes of mixing. This delayed effect is considered important for reducing Mooney viscosity buildup of the rubber composition in promoting better and more efficient processing within the internal rubber mixer.

It can also be seen that the Experimental Rubber Sample I has a faster torque speed after the 4 minute mixing period. This is indicative of the fact that faster (shorter) rubber molding times are possible for the manufacture of rubber artifacts.

EXAMPLE V

Rubber reinforcing effects of treated allyl precipitated silica and treated allyl silica are evaluated.

Precipitated silica is identified herein as Silica Pea treated allyl precipitated silica is identified herein as Silica A-P.

The silica gel is identified herein as Silica G and the allyl treated silica gel is herein identified as Silica A-G.

For this Example, the precipitated silica used was Rhodian Zeosil 1165 MP ™.

For this Example, the silica gel used was Siliabond ™ from Silicycle Company.

Table D below represents the general rubber formulation. Parts and percentages are by weight unless otherwise indicated.

Non-Productive Mixing Stage Table (Ν P) Parts

Rubber 1,4-polybutadiene7 30

Styrene / butadiene rubber prepared by solution polymerization (S-SBR) 8 70

Naphthenic Rubber Processing Oil 11

Wax (microcrystalline) 1

Fatty Acid 2 2

Coupling agent3 0 and 5.2

Carbon black4 5.2

Silica Z (untreated precipitated silica) 6 0 and 65

Silica A-P (treated allyl precipitated silica) 0 and 65

Silica A-G (treated allyl silica gel) 0 and 65

Productive Mixing Stage (PR)

Sulfur 1.5 and 2

Sulfur Curing Accelerator, Sulphenamide 1.6

Zinc Oxide 1

Amine Based Antioxidant 0.5

Secondary Sulfur Curing Accelerator, Diphenylguanidine 0.75e1.5

7-1,4-polybutadiene rubber as Budene ™ 1207 from "The Goodyear Tire & Rubber Company"

8SBR prepared in solution polymerization as Solflex ™ 33H23 from The Go-odyear Tire & Rubber Company

Rubber samples N, O and P were prepared in the manner of Example I. The curing behavior and physical properties of the respective Samples are given in Table 4 below. For the cured Rubber Samples, the Samples were cured for about 30 minutes at a temperature of about 150 ° C.

Rubber Samples are identified as Control Sample N (with a precipitated silica reinforcement), Experimental Rubber Sample O (with an allylated precipitated AP silica) and Experimental Rubber Sample P (with an aliltrated AG silica gel) .

Table 4

Experimental Control

Sample Samples

Materials (phr) N QP

Cis 1,4-polybutadiene rubber 30 30 30 <table> table see original document page 21 </column> </row> <table>

It can be seen from Table 4 that the rubber sample) containing AP Silica (the treated allyl precipitated silica) had stress-stretching, cured rubber physical properties such as tensile strength, modulus and elongation as well as dynamic physical properties. (determined by RPA) as a storage modulus (G ') and delta tan, similar to Precipitated silica rubber sample N (which was not treated with allyl) together with a traditional silica coupling agent.

This is particularly significant in that the precipitated (non-allyl treated) silica required the silica coupling agent to achieve cured rubber properties similar to the treated allyl precipitated silica without an inclusion of the silica coupling agent.

It is believed that this remark is indeed remarkable as constituting a significant departure from previous practice.

In addition, these generic rubber properties of Rubber Sample N are dramatically and significantly better than the general rubber properties of Rubber Sample O (using allyl-treated silica gel) including significantly reduced energy to achieve a 300 percent stretch.

This is particularly significant in the sense that it was only the allyl-treated precipitated silica (rubber-reinforced quality silica) that was also found to have the beneficial cured rubber properties instead of the comalyl-treated silica gel.

These significant physical differences are considered here as an obvious indication that the allyl-treated precipitated silica (Silica A - Silica P) has a higher rubber reinforcing capacity than the treated allyl silica gel (Silica A - Silica G). ).

Furthermore, it is seen that treatment of the silica gel with allyl silane was not sufficient to make the silica gel suitable for rubber reinforcement.

Therefore, it is evident that the silica structure is significant, particularly the combination for the precipitated silica of the BET nitrogen surface area, the surface areaCTAB and a BET / CTAB area ratio in a range of 0.8 to 1.3.

Accordingly, it is considered herein that a combination of the specific precipitated silica structure and its treatment with allyl is a significant aspect of this invention in the provision of rubber reinforcement.

While some representative embodiments and details are shown by way of illustration of the invention, it will be apparent to those skilled in the art that various changes and modifications may be made without departing from the spirit and scope of the invention.

Claims (10)

1. Functionalized allyl precipitated silica, characterized in that it comprises precipitated silica containing at least one substituent of the allyl group, wherein the functionalized allyl precipitated silica is represented by the general formula (I): R2a (I) IZ -O- Si-R1cIR3b wherein Z represents the precipitated silica; R 2 and R 3 are the same or different radicals composed of an alkyl group containing from 1 to 4 carbon atoms, a cycloalkyl group, a phenyl group, an alkene group containing from 3 to 18 carbon atoms or a cycloalkene radical having from 5 to 4 carbon atoms. 8 carbon atoms and R1 is an allyl hydrogen containing radical composed of at least one of: -CH2-CH = CH2, -CH2-CH = CH-CH3, -CH2-CH = C- (CH3) 2 and-CH2 -C (CH3) = CH-CH3 where a is an integer in a range from 0 to 2 b is an integer in a range from 0 to 2 and c is an integer in a range from 1 to 3. 2. Functionalized allyl precipitated silica, characterized in that it comprises precipitated silica treated with at least one allyl silane, wherein said allyl silane has the general structure formula (II) R2a (II) IXd - Si-R1cIR3, although R2 and R3 are the same or different. being composed of an alkoxy group having from 1 to 8 carbon atoms a cycloalkoxy group containing from 5 to 8 carbon atoms, and an alkyl group containing from 1 to 4 carbon atoms, a cyclohexyl group, a groupuphenyl an alkene containing from 3 to 18 carbon atoms, or a cycloalkene containing from 5 to 8 carbon atoms: wherein X is a chlorine, hydroxy or hydrogen atom, where R1 is an allyl hydrogen-containing radical composed of at least one of: -CH2 -CH = CH2, -CH2-CH = CH-CH3, -CH2-CH = C- (CH3) 2 and -CH2-C (CH3) = CH-CH3 where a is an integer with one range 0 to 3, b is an integer in a range from 0 to 3, c is an integer in a range from 1 to 3, and d is an integer in a range from 0 to 3, and the sum of a, bc, d = 4, where at at least one X, R2 and R3 is present, wherein if d is = 0, at least one of R2 and R3 is an alkoxy group. A method of preparing a functionalized allyl precipitated silica, characterized in that it comprises treating a precipitated silica with hydroxyl groups with at least one allyl silane compound, wherein the allyl silane compound has the general structural formula (II): <formula> formula see wherein R2 and R3 are the same or different being composed of an alkoxy group having from 1 to 8 carbon atoms a cycloalkoxy group containing from 5 to 8 carbon atoms, and a alkyl group containing from 1 to 4 carbon atoms, a cyclohexyl group, a groupuphenyl, an alkene containing from 3 to 18 carbon atoms, or a cycloalkene containing 5 to 8 carbon atoms: where X is a chlorine atom, a hydroxy or a hydrogen wherein R1 is an allyl hydrogen containing hydrocarbon radical; composed of at least one of: -CH 2 -CH = CH 2, -CH 2 -CH = CH-CH 3, -CH 2 -CH = C- (CH 3) 2 and -CH 2 -C (CH 3) = CH-CH 3 where a is an integer with a range from 0 to 3, b is an integer in a range from 0 to 3, c is an integer in a range from 1 to 3, and d is an integer in a range from 0 to 3, and a somade a, bc d = 4, wherein at least one X, R2 and R3 is present, wherein if d is = 0, at least one of R2 and R3 is an alkoxy group. Functionalized allyl precipitated silica, characterized in that it is prepared by the method of claim 3. Rubber composition, characterized in that it is provided with at least one sulfur cured sulfur vulcanizable elastomer containing at least one reinforcing filler composed of: (A) the functionalized allyl precipitated silica of Claim 1, or (B) the functionalized allyl precipitated silica of at least one carbon black compound and the precipitated silica without an allyl substituent. Rubber composition, characterized in that it is provided with at least one sulfur cured sulfur vulcanizable elastomer containing at least one reinforcing charge composed of: (A) the functionalized allyl precipitated silica of Claim 2, or (B) the functionalized allyl precipitated silica of at least one carbon black compound and the precipitated silica without an allyl substituent. Rubber composition according to Claim 5, characterized in that it contains a silica coupling agent with a reactive fraction with hydroxyl groups contained in the precipitated silica and another different fraction interactive with the sulfur-volatile elastomers. Rubber composition according to Claim 7, characterized in that the sulfur vulcanizable elastomer is composed of at least one of: (A) at least one isoprene and 1,3-butadiene polymers and styrene copolymers and at least one of isoprene and 1,3-butadiene, (B) coupled elastomer composed of at least one isoprene and 1,3-butadiene polymer and the styrene copolymer with at least one of isoprene and 1,3-butadiene wherein the coupled elastomer is at least one tin silica coupled elastomer, and (C) a functionalized elastomer of at least one styrene / butadiene copolymer elastomer (SBR), useful 1,4-polybutadiene elastomer and 1,4 elastomer wherein said functionalized elastomers contain functional groups composed of: (1) reactive amine functional group with said functionalized allyl precipitated silica, or (2) reactive siloxy functional group with said charge rubber reinforcement of silica functionalized allyl precipitated, or (3) combination of the reactive siloxy and amine functional groups with the functionalized allyl silica, or (4) reactive silane / thiol functional group with said functionalized allyl silica, or (5) reactive hydroxyl functional groups with said functionalized allyl precipitated silica, or (6) reactive epoxy groups with said functionalized allyl precipitated silica, or (7) reactive carboxyl groups with said functionalized allyl precipitated silica. Rubber composition according to Claim 5, characterized in that the precipitated silica is allyl functionalized by: (A) treating the precipitated silica with the allylane prior to addition to the rubber composition, or (B) treating the precipitated silica with allyl silane in situ in the rubber composition. Tire having at least one component, characterized in that it is provided with a rubber composition according to any preceding claims 5 to 9.