Abstract:
Novel carbon blacks that impart advantageous properties to rubber and plastic compositions and may be utilized in the place of lamp blacks, thermal carbon blacks and blends of carbon blacks. Also disclosed are novel rubber and plastic compositions incorporating the novel carbon blacks which exhibit the advantageous combinations of compound processing and physical performance properties.

Description:
This application is a continuation-in-part of U.S. patent application Ser. No. 08/202,244, filed Feb. 25, 1994, now U.S. Pat. No. 5,456,750 which in turn is a continuation-in-part of U.S. patent application Ser. No. 08/081,881, filed Jun. 25, 1993, which in turn is a continuation-in-part of U.S. patent application Ser. No. 07/935,794, filed Aug. 27, 1992, both now abandoned. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to new carbon blacks which are suitable for various applications and particularly well suited for use in plastic and rubber compositions. 
     BACKGROUND 
     Carbon blacks may be utilized as pigments, fillers, reinforcing agents, and for a variety of other applications. They are widely utilized as fillers and reinforcing pigments in the compounding and preparation of rubber compositions and plastic compositions. 
     Carbon blacks are generally characterized on the basis of their properties including, but not limited to, their surface areas, surface chemistry, aggregate sizes, and particle sizes. The properties of carbon blacks are analytically determined by tests known to the art, including iodine adsorption number (I 2  No.), dibutyl phthalate adsorption (DBP), Tint value (TINT), Dst, Dmode and M-Ratio that is defined as the median aggregate Stokes diameter divided by the mode aggregate Stokes diameter (M-Ratio=Dst/Dmode). 
     From the prior art several references are known. These include U.S. Pat. Nos. 4,366,139; 4,221,772; 3,799,788; 3,787,562; Soviet Union Patent No. 1279991; Canadian Patent No. 455504; Japanese Patent No. 61-047759; British Patent No. 1022988; and Japanese Patent No. 61-283635. None of the aforementioned references disclose the carbon black products of the present invention. Moreover, none of the aforementioned references describe the use for which the carbon blacks of the present invention are intended. 
     SUMMARY OF THE INVENTION 
     We have discovered new classes of carbon blacks advantageous for use in rubber and plastic compositions where compound processing and physical properties such as mixing energy, viscosity, cure rate, extrusion shrinkage, tensile, fatigue life, compression set, hardness, resistivity and surface appearance are important. These carbon blacks have been found to provide unique combinations of properties that make them especially well suited for use in extrusion, molded part, hose and belt applications. 
     The first class of carbon blacks has an Iodine adsorption number (I 2  No.) of 10-19 mg/g (milligrams of I 2  per gram carbon black); a DBP (dibutyl phthalate value) of 70-95 cc/100 g (cubic centimeters of diburyl phthalate per 100 grams carbon black); and a volatiles content of less than 2%, by weight. 
     The second class of carbon blacks has an I 2  No. of 14-18 mg/g; a DBP of 34-44 cc/100 g; and a volatiles content of less than 2%, by weight. 
     The third class of carbon blacks has an I 2  No. of 8-17 mg/g; a DBP of 45-55 cc/100 g; and a volatiles content of less than 2%, by weight. 
     The fourth class of carbon blacks has an I 2  No. of 28-43 mg/g; a DBP of 28-47 cc/100 g; and a volatiles content of less than 2%, by weight. Preferably this class of carbon blacks is characterized by an I 2  No. of 30-42 mg/g. 
     The fifth class of carbon blacks has an I 2  No. of 8-11 mg/g; a DBP of 28-38 cc/100 g; and a volatiles content of less than 2%, by weight. 
     The sixth class of carbon blacks has an I 2  No. of 8-32 mg/g; a DBP of 28-53 cc/100 g; and an M-Ratio of the carbon black aggregate of 1.25-2.00. Preferably the sixth class of carbon blacks has a volatiles content of less than 2%, by weight. 
     The seventh class of carbon blacks has an I 2  No. of 8-22 mg/g; a DBP of 54-70 cc/100 g; and an M-Ratio of the carbon black aggregate of 1.25-2.00. Preferably the seventh class of carbon blacks has a volatiles content of less than 2%, by weight. 
     The eighth class of carbon blacks has an I 2  No. of 8-32 mg/g; a DBP of 71-150 cc/100 g; and an M-Ratio of the carbon black aggregate of 1.25-2.00. Preferably the eighth class of carbon blacks has a volatiles content of less than 2%, by weight. 
     We have also discovered new classes of rubber and plastic compositions containing the carbon blacks. 
     The carbon blacks of the present invention may be produced in a furnace carbon black reactor having a combustion zone, a transition zone, and a reaction zone. A carbon black yielding feedstock is injected into a hot combustion gas stream. The resultant mixture of hot combustion gases and feedstock passes into the reaction zone. Pyrolysis of the carbon black yielding feedstock is stopped by quenching the mixture after the carbon blacks of the present invention have been formed. Preferably pyrolysis is stopped by injecting a quenching fluid. The process for preparing the novel carbon blacks of the present invention will be described in greater detail hereinafter. 
     The rubbers and plastics for which the novel carbon blacks of this invention are effective include natural and synthetic rubbers and plastics. Generally, amounts of the carbon black product ranging from about 10 to about 300 parts by weight can be used for each 100 parts by weight of rubber or plastic. 
     Among the rubbers or plastics suitable for use with the present invention are natural rubber, synthetic rubber and their derivatives such as chlorinated rubber; copolymers of from about 10 to about 70 percent by weight of styrene and from about 90 to about 30 percent by weight of butadiene such as copolymer of 19 parts styrene and 81 parts butadiene, a copolymer of 30 parts styrene and 70 parts butadiene, a copolymer of 43 parts styrene and 57 parts butadiene and a copolymer of 50 parts styrene and 50 parts butadiene; polymers and copolymers of conjugated dienes such as polybutadiene, polyisoprene, polychloroprene, and the like, and copolymers of such conjugated dienes with an ethylenic group-containing monomer copolymerizable therewith such as styrene, methyl styrene, chlorostyrene, acrylonitrile, 2-vinyl-pyridine, 5-methyl-2-vinylpyridine, 5-ethyl-2-vinylpyridine, 2-methyl-5-vinylpyridine, alkyl-substituted acrylates, vinyl ketone, methyl isopropenyl ketone, methyl vinyl ether, alphamethylene carboxylic acids and the esters and amides thereof such as acrylic acid and dialkylacrylic acid amide; also suitable for use herein are copolymers of ethylene and other high alpha olefins such as propylene, butene-1 and penetene-1; particularly preferred are the ethylene-propylene copolymers wherein the ethylene content ranges from 20 to 90 percent by weight and also the ethylene-propylene polymers which additionally contain a third monomer such as dicyclopentadiene, 1,4-hexadiene and methylene norbornene. Additionally preferred polymeric compositions are olefins such as polypropylene and polyethylene. 
     An advantage of the carbon blacks of the present invention is that the carbon blacks are useful for incorporation into natural rubbers, synthetic rubbers, plastics or blends thereof for industrial applications, particularly where compound processing and part performance characteristics are important. 
     A further advantage of the carbon blacks of the present invention is that certain of the carbon blacks of the present invention will replace blends of carbon blacks in applications that currently require the use of blends of carbon blacks to achieve desired performance characteristics. 
     Other advantages of the present invention will become apparent from the following more detailed description of the invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a cross-sectional view of a portion of one type of furnace carbon black reactor which may be utilized to produce the carbon blacks of the present invention. 
     FIG. 2 is a sample histogram of the weight fraction of the aggregates of a carbon black sample versus the Stokes Diameter in a given sample. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The analytical properties of each of the classes of carbon blacks of the present invention are set forth in Table 1 below: 
     
                       TABLE 1______________________________________     I.sub.2 No.             DBP       Volatiles ContentClass     (mg/g)  (cc/100 g)                       (%, by weight)                                 M-Ratio______________________________________First     10-19   70-95     &lt;2        N.A.Second    14-18   34-44     &lt;2        N.A.Third      8-17   45-55     &lt;2        N.A.Fourth    28-43   28-47     &lt;2        N.A.Fourth Preferred     30-42   28-47     &lt;2        N.A.Fifth      8-11   28-38     &lt;2        N.A.Sixth      8-32   28-53     N.A.      1.25-2.00Seventh    8-22   54-70     N.A.      1.25-2.00Eighth     8-32   71-150    N.A.      1.25-2.00______________________________________ N.A. = not applicable 
    
     The carbon blacks of the present invention may be produced in a modular, also referred to as &#34;staged&#34;, furnace carbon black reactor. A section of a typical modular furnace carbon black reactor which may be utilized to produce the carbon black of the present invention is depicted in FIG. 1. Other details of a typical modular furnace carbon black reactor may be found, for example, in the description contained in U.S. Pat. No. 3,922,335, the disclosure of which is herein incorporated by reference. A carbon black reactor particularly well-suited for the production of the carbon blacks of the present invention is described in commonly assigned U.S. patent application Ser. No. 07/818,943, filed Jan. 10, 1992, now issued as U.S. Pat. No. 5,190,739 on Mar. 2, 1993, the disclosure of which is hereby incorporated by reference. The carbon blacks of the Examples described herein were made by the process described in the &#39;739 patent. The &#39;739 patent describes a process for producing carbon blacks wherein auxiliary hydrocarbon is added to the reaction zone of a multistage reactor and the primary combustion and overall combustion of the reaction are adjusted so that the SSI of the process is less than zero. The SSI of the process may be determined by the following relationships: ##EQU1## 
     |SAS mf  |=Absolute value of SAS mf  ; 
     Δ(DBP) mf  =the change in DBPA of the carbon black due to a change in feedstock flow rate while all other process operating conditions are held constant; 
     Δ(Iodine Number) mf  =the change in iodine adsorption number of the carbon black due to a change in feedstock flow rate while all other process operating conditions are held constant; 
     Δ(DBP) ah  =the change in DBPA of the carbon black due to a change in auxiliary hydrocarbon flow rate while all other process operating conditions are held constant; and 
     Δ(Iodine Number) ah  =the change in iodine adsorption number of the carbon black due to a change in auxiliary hydrocarbon flow rate while all other process operating conditions are held constant. 
     The &#34;auxiliary hydrocarbon&#34; comprises hydrogen or any hydrocarbon having a molar hydrogen-to-carbon ratio greater than the molar hydrogen-to-carbon ratio of the feedstock. 
     Referring to FIG. 1, the carbon blacks of the present invention may be produced in a furnace carbon black reactor 2, having a combustion zone 10, which has a zone of converging diameter 11, transition zone 12, entry section 18, and reaction zone 19. The diameter of the combustion zone 10, up to the point where the zone of converging diameter 11 begins, is shown as D-1; the diameter of zone 12, as D-2; the diameters of the stepped entry section, 18, as D-4, D-5, D-6, and D-7; and the diameter of zone 19, as D-3. The length of the combustion zone 10, up to the point where the zone of converging diameter 11 begins, is shown as L-1; the length of the zone of converging diameter is shown as L-2; the length of the transition zone is shown as L-3; and the lengths of the steps in the reactor entry section, 18, as L-4, L-5, L-6 and L-7. 
     To produce carbon blacks, hot combustion gases are generated in combustion zone 10, by contacting a liquid or gaseous fuel with a suitable oxidant stream such as air, oxygen, mixtures of air and oxygen or the like. Among the fuels suitable for use in contacting the oxidant stream in combustion zone 10 to generate the hot combustion gases are any of the readily combustible gas, vapor, or liquid streams such as natural gas, hydrogen, carbon monoxide, methane, acetylene, alcohol, or kerosene. It is generally preferred, however, to utilize fuels having a high content of carbon-containing components and in particular, hydrocarbons. The ratio of air to natural gas utilized to produce the carbon blacks of the present invention may preferably be from about 10:1 to about 100:1. To facilitate the generation of hot combustion gases, the oxidant stream may be preheated. 
     The hot combustion gas stream flows downstream from zones 10 and 11 into zones 12, 18, and 19. The direction of the flow of hot combustion gases is shown in the figure by the arrow. Carbon black-yielding feedstock 30 is introduced at point 32 (located in zone 12), and/or at point 70 (located in zone 11). Suitable for use herein as carbon black-yielding hydrocarbon feedstocks, which are readily volatilizable under the conditions of the reaction, are unsaturated hydrocarbons such as acetylene; olefins such as ethylene, propylene, butylene; aromatics such as benzene, toluene and xylene; certain saturated hydrocarbons; and other hydrocarbons such as kerosenes, naphthalenes, terpenes, ethylene tars, aromatic cycle stocks and the like. 
     The distance from the end of the zone of converging diameter 11 to point 32 is shown as F-1. Generally, carbon black-yielding feedstock 30 is injected in the form of a plurality of streams which penetrate into the interior regions of the hot combustion gas stream to insure a high rate of mixing and shearing of the hot combustion gases and the carbon black-yielding feedstock so as to rapidly and completely decompose and convert the feedstock to carbon black. 
     Auxiliary hydrocarbon is introduced at point 70 through probe 72 or through auxiliary hydrocarbon passages 75 in the walls which form the boundaries of zone 12 of the carbon black forming process or through auxiliary hydrocarbon passages 76 in the walls which form the boundaries of zones 18 and/or 19 of the carbon black forming process. The auxiliary hydrocarbon may be introduced at any location between the point immediately after the initial combustion reaction of the first-stage fuel and the point immediately before the end of formation of carbon black provided that unreacted auxiliary hydrocarbon eventually enters the reaction zone. 
     The distance from point 32 to point 70 is shown as H-1. 
     In the Examples described herein, the auxiliary hydrocarbon was introduced through either three or four orifices in the same axial plane as the carbon black yielding feedstock streams. The orifices are arranged in an alternating pattern, one feedstock, the next auxiliary hydrocarbon, spaced evenly around the outer periphery of section 12. As will be noted, however, this is merely exemplary and is not intended to be limiting of the methods usable for introducing auxiliary hydrocarbon. 
     The mixture of carbon black-yielding feedstock and hot combustion gases flows downstream through zone 12 into zone 18 and then into zone 19. Quench 60, located at point 62, injecting quenching fluid 50, which may be water, is utilized to stop chemical reaction when carbon blacks are formed. Point 62 may be determined in any manner known to the art for selecting the position of a quench to stop pyrolysis. One method for determining the position of the quench to stop pyrolysis is by determining the point at which an acceptable toluene extract level for the carbon black is reached. Toluene extract level may be measured by using ASTM Test D1618-83 &#34;Carbon Black Extractables--Toluene Discoloration&#34;. Q is the distance from the beginning of zone 18 to quench point 62, and will vary according to the position of Quench 60. 
     After the mixture of hot combustion gases and carbon black-yielding feedstock is quenched, the cooled gases pass downstream into any conventional cooling and separating means whereby the carbon blacks are recovered. The separation of the carbon black from the gas stream is readily accomplished by conventional means such as a precipitator, cyclone separator or bag filter. This separation may be followed by pelletizing using, for example, a wet pelletizer. 
     The following testing procedures are used in evaluating the analytical and physical properties of the carbon blacks of the present invention. 
     Iodine adsorption number of the carbon blacks (I 2  No.) was determined according to ASTM Test Procedure D1510. Tinting strength (Tint) of the carbon blacks was determined according to ASTM Test Procedure D3265-85a. The DBP (dibutyl phthalate value) of the carbon blacks was determined according to the procedure set forth in ASTM D3493-86. The cetyl-trimethyl ammonium bromide absorption value (CTAB) of the carbon blacks was determined according to ASTM Test Procedure D3765-85. 
     Volatiles content of the carbon blacks (in %, by weight) was determined by the following Cabot Test Procedure. 
     Volatile Content Of Carbon Blacks 
     This method covers the determination of the volatile content of carbon black at 950° C. 
     Equipment 
     1. Muffle Furnace, capable of temperature regulation of 950°±25° C. 
     2. Vycor or glazed porcelain, high-form crucible, 50 cm 3  capacity, With proper size cover. A smaller capacity crucible, 30 or 40 cm 3 , call be used for pelleted blacks. 
     3. Analytical Balance having a sensitivity of 0.1 mg. 
     4. Desiccator filled with indicating desiccant. (A metal desiccator will hasten the cooling process.) 
     5. Oven, convection or vacuum type, capable of temperature regulation of 125±1° C. 
     6. Tongs. 
     7. Insulating gloves for protection from high temperatures. 
     8. Tamping Rod. 
     9. Interval Timer. 
     Procedure 
     1. Place an adequate amount of carbon black to complete test into an aluminum dish with cover. 
     2. Dry an adequate sample of the carbon black one hour or longer at 125° C.±1° C. until constant weight is obtained. 
     3. Cool in desiccator to room temperature. 
     4. Ignite the crucible with cover in muffle furnace at 950° C.±25° C. for 1/2 hour. (Never touch the crucible or cover with bare hands. Always use Asbestos gloves and tongs when transferring the crucible and cover to and from the muffle furnace. Always keep the crucible covered.) Place crucible and cover in desiccator. Cool to room temperature and weigh crucible and cover to the nearest 0.1 mg. 
     5. Fill crucible to within approximately five millimeters of the top. For fluffy samples, tamp the black with a tamping rod to minimize trapped air, and continue filling crucible to within approximately five millimeters of the top. Replace cover and weigh cover, crucible and carbon. Record weight to the nearest 0.1 mg. 
     6. Place the covered crucible in muffle furnace at 950° C.±25° C. for 7 minutes. Place crucible and cover in desiccator and allow to cool to room temperature. Record weight to the nearest 0.1 mg. 
     Calculations 
     Calculate the percent of volatiles as follows: 
     
         %A= (C-D)/(C-B)!×100 
    
     Where: 
     A=Percent Volatiles 
     B=Weight Crucible and cover, in grams. 
     C=Weight of Crucible, cover and sample, in grams. 
     D=Weight of Crucible, cover and sample after fired, in grams. 
     Dmode, and Dst of the carbon blacks were determined from a histogram of the weight fraction of carbon black versus the Stokes diameter of the carbon black aggregates, as shown in FIG. 2. The data used to generate the histogram are determined by the use of a disk centrifuge such as the one manufactured by Joyce Loebl Co. Ltd. of Tyne and Wear, United Kingdom. The following procedure is a modification of the procedure described in the instruction manual of the Joyce Loebl disk centrifuge file reference DCF 4.008 published on Feb. 1, 1985, the teachings of which are hereby incorporated by reference, and was used in determining the data. 
     The procedure is as follows. 10 mg (milligrams) of a carbon black sample are weighed in a weighing vessel, then added to 50 cc of a solution of 10% absolute ethanol and 90% distilled water which is made 0.05% NONIDET P-40 surfactant (NONIDET P-40 is a registered trademark for a surfactant manufactured and sold by Shell Chemical Co.). The resulting suspension is dispersed by means of ultrasonic energy for 15 minutes using Sonifier Model No. W 385, manufactured and sold by Heat Systems Ultrasonics Inc., Farmingdale, N.Y. 
     Prior to the disk centrifuge run the following data are entered into the computer which records the data from the disk centrifuge: 
     1. The specific gravity of carbon black, taken as 1.86 g/cc; 
     2. The volume of the solution of the carbon black dispersed in a solution of water and ethanol, which in this instance is 0.5 cc.; 
     3. The volume of spin fluid, which in this instance is 10 cc of water; 
     4. The viscosity of the spin fluid, which in this instance is taken as 0.933 centipoise at 23 degrees C.; 
     5. The density of the spin fluid, which in this instance is 0.9975 g/cc at 23 degrees C.; 
     6. The disk speed, which in this instance is 8000 rpm; 
     7. The data sampling interval, which in this instance is 1 second. 
     The disk centrifuge is operated at 8000 rpm while the stroboscope is operating. 10 cc of distilled water are injected into the spinning disk as the spin fluid. The turbidity level is set to 0; and 1 cc of the solution of 10% absolute ethanol and 90% distilled water is injected as a buffer liquid. The cut and boost buttons of the disk centrifuge are then operated to produce a smooth concentration gradient between the spin fluid and the buffer liquid and the gradient is monitored visually. When the gradient becomes smooth such that there is no distinguishable boundary between the two fluids, 0.5 cc of the dispersed carbon black in aqueous ethanol solution is injected into the spinning disk and data collection is started immediately. If streaming occurs the run is aborted. The disk is spun for 20 minutes following the injection of the dispersed carbon black in aqueous ethanol solution. Following the 20 minutes of spinning, the disk is stopped, the temperature of the spin fluid is measured, and the average of the temperature of the spin fluid measured at the beginning of the run and the temperature of the spin fluid measured at the end of the run is entered into the computer which records the data from the disk centrifuge. The data is analyzed according to the standard Stokes equation and is presented using the following definitions: 
     Carbon black aggregate--a discrete, rigid colloidal entity that is the smallest dispersible unit; it is composed of extensively coalesced particles; 
     Stokes diameter--the diameter of a sphere which sediments in a viscous medium in a centrifugal or gravitational field according to the Stokes equation. A non-spherical object, such as a carbon black aggregate, may also be represented in terms of the Stokes diameter if it is considered as behaving as a smooth, rigid sphere of the same density, and rate of sedimentation as the object. The customary units are expressed in nanometer diameters. 
     Mode (Dmode for reporting purposes)--The Stokes diameter of the carbon black aggregate at the point of the peak (Point A of FIG. 2 herein) of the distribution curve for Stokes diameter. 
     Median Stokes diameter--(Dst for reporting purposes) the point on the distribution curve of Stokes diameter of carbon black aggregate where 50% by weight of the sample is either larger or smaller. It therefore represents the median value of the determination. 
     The modulus, tensile and elongation of the EPDM compositions were measured by the procedure set forth in ASTM D412-87. 
     The Shore A Hardness of the EPDM compositions was determined according to the procedure set forth in ASTM D-2240-86. 
     Rebound data for the EPDM compositions was determined according to the procedure set forth in ASTM D1054, utilizing a ZWICK Rebound Resilience Tester, Model 5109, manufactured by Zwick of America, Inc., Post Office Box 997, East Windsor, Conn. 06088. Instructions for determining the rebound values accompany the instrument. 
     The Compression set of the EPDM compositions was determined according to the procedure set forth in ASTM D395, wherein the composition was tested at 150° F. for 70 hours. 
     The extrusion shrinkage of the EPDM compositions was determined by the procedure set forth in ASTM D-3674. The extrusion shrinkage was measured on the BRABENDER extruder at 100° C. and 50 rpm using a 5 mm diameter die. 
     The viscosity of the EPDM compositions was determined by the procedure set forth in ASTM D-1646 using a Monsanto MPT capillary rheometer maintained at 100° C. using a die having a ratio of L/D&#39;=16 and D=0.0787 mm (millimeter). The shear rate ranged from 10 to 150 1/seconds. 
     Mixing energy is the total amount of energy put into the compositions which is determined by integrating the mixing torque curve over the course of the mixing cycle, described hereinafter. 
     Cure characteristics of the EPDM compositions were measured using a Monsanto MDR curemeter maintained at 160° C. The time to reach 90% cure reaction (t&#39;90), the total torque change during cure reaction (ΔL) and cure rate index (CRI; (CRI=1/(t&#39;90-ts1)×100) where ts1=the time when the torque level is 1 unit above minimum torque (ts1 is also referred to as scorch time)) are reported for the example EPDM compositions. The tests were conducted according to the instructions furnished with the Monsanto MDR curemeter. 
     Composition resistivity was measured on plaque samples 2 inches wide by 6 inches long by 0.085 inch thick. The plaques were painted on both ends with a half inch width of silver paint. The sample was conditioned to produce a stable reading by cycling from room temperature to 100° C. and back to room temperature, followed by aging at 90° C. for 24 hours. The stabilized resistivity was measured at the end of the aging cycle, and once again after the sample was allowed to cool back to room temperature. 
     The effectiveness and advantages of the present invention will be further illustrated by the following examples. 
     EXAMPLES 1-9 
     Examples of the novel carbon blacks of the present invention were prepared in a reactor generally described herein, and as depicted in FIG. 1, utilizing the reactor conditions and geometry set forth in Table 3. The fuel utilized in the combustion reaction was natural gas. The auxiliary hydrocarbon used was also natural gas. The liquid feedstock utilized had the properties indicated in Table 2 below: 
     
                       TABLE 2______________________________________Feedstock Properties            EXAMPLES            1-8    9______________________________________Hydrogen/Carbon Ratio              0.93     1.00Hydrogen (wt. %)   7.19     7.71Carbon (wt. %)     92.1     91.94Sulfur (wt. %)     0.30     0.23Nitrogen (wt. %)   0.41     0.22A.P.I. Gravity 15.6/15.6° C.              -1.6     +6.4(60/60° F.)  ASTM D-287!Specific Gravity 15.5/15.6° C.              1.092    1.026(60/60° F.)  ASTM D-287!Viscosity, SUS (54.4° C.) m.sup.2 /s              2.6 × 10.sup.-5                       1.3 × 10.sup.-5 ASTM D-88!Viscosity, SUS (98.9° C.) m.sup.2 /s              5.2 × 10.sup.-6                       4.8 × 10.sup.-6 ASTM D-88!______________________________________ 
    
     The reactor conditions and geometry were as set forth in Table 3 below. 
     
                                           TABLE 3__________________________________________________________________________Reactor Geometry and Operating Conditions.Example No.   1  2   3  4   5  6   7  8   9__________________________________________________________________________D-1 (m) 0.18      0.18          0.18             0.18                 0.18                    0.18                        0.18                           0.18                               0.18D-2 (m) 0.11      0.11          0.11             0.11                 0.13                    0.11                        0.13                           0.13                               0.10D-3 (m) 0.69      0.69          0.69             0.69                 0.91                    0.69                        0.69                           0.69                               0.91D-4 (m) 0.25      0.25          0.25             0.25                 0.26                    0.25                        0.25                           0.36                               0.23D-5 (m) 0.69      0.69          0.69             0.69                 0.33                    0.69                        0.69                           0.69                               0.91D-6 (m) 0.69      0.69          0.69             0.69                 0.91                    0.69                        0.69                           0.69                               0.91D-7 (m) 0.69      0.69          0.69             0.69                 0.91                    0.69                        0.69                           0.69                               0.91L-1 (m) 0.61      0.61          0.61             0.61                 0.61                    0.61                        0.61                           0.61                               0.61L-2 (m) 0.30      0.30          0.30             0.30                 0.30                    0.30                        0.30                           0.30                               0.30L-3 (m) 0.23      0.23          0.23             0.23                 0.23                    0.23                        0.23                           0.23                               0.23L-4 (m) 0.30      0.30          0.30             0.30                 0.30                    0.30                        0.30                           0.14                               0.30L-5 (m) 0.10      0.10          0.10             0.10                 0.23                    0.10                        0.10                           0.10                               0.11L-6 (m) 0.00      0.00          0.00             0.00                 0.00                    0.00                        0.00                           0.00                               0.00L-7 (m) 0.00      0.00          0.00             0.00                 0.00                    0.00                        0.00                           0.00                               0.00F-1 (m) 0.11      0.11          0.11             0.11                 0.11                    0.11                        0.11                           0.11                               0.11Q (m)   7.93      7.93          7.93             7.93                 7.93                    7.93                        19.8                           7.93                               12.2Comb. Air   0.373      0.373          0.634             0.634                 0.634                    0.373                        0.448                           0.634                               0.472(SCMS)Comb. Air   755      755 755             755 755                    755 755                           755 755Preheat (K)Burner Nat.   0.9      0.9 2.0             2.0 1.8                    0.9 1.4                           2.0 1.0Gas(10.sup.2 × SCMS)Feedstock Inj.   0.198      0.218          0.198             0.198                 0.185                    0.218                        0.198                           0.206                               0.226OrificeDiam. (cm)No. Feedstock   3  3   3  3   4  3   4  4   3Inj. OrificesFeedstock   1.3      1.2 1.9             2.3 1.3                    1.2 1.6                           2.1 1.2Rate(10.sup.4 × m.sup.3 /s)Feedstock   483      463 451             438 467                    439 467                           415 362Temp. (K)K.sup.+ Conc. (g/m.sup.3)   0.0      93.1          81.0             0.0 388.0                    11.4                        0.8                           20.3                               443Aux. HC Inj.   0.635      0.635          0.635             0.635                 0.635                    0.635                        0.635                           0.635                               0.5080rificeDiam. (cm)No. Aux.   3  3   3  3   4  3   4  4   3HC Inj.Orifices (*)Aux. HC Rate   2.4      2.3 2.1             3.9 3.1                    2.1 1.7                           0.0 3.5(10.sup.2 × SCMS)Primary 400      450 400             400 300                    450 400                           400 500Comb. (%)Overall 21.7      23.3          25.4             21.5                 22.9                    23.5                        21.4                           25.8                               25.6Comb. (%)__________________________________________________________________________ Inj. = injection; Comb. = combustion; HC = hydrocarbon; Diam = diameter; (*)  The feedstock and auxiliary hydrocarbon orifices were arranged in th same axial plane in an alternating sequence around the periphery of the reactor. 
    
     The carbon blacks produced in runs 1-9 were then analyzed according to the procedures described herein. The analytical properties of the carbon blacks were as set forth in Table 4. 
     
                                           TABLE 4__________________________________________________________________________Carbon Black Analytical PropertiesExample 1  2   3  4   5  6   7  8   9__________________________________________________________________________I.sub.2 No. (mg/g)   22.1      16.5          28.0             16.3                 40.7                    15.8                        28.7                           57.9                               16.5DBP (cc/100 g)   132.5      39.1          35.8             84.6                 43.1                    46.9                        119.5                           95.8                               30.0CTAB(m.sup.2 /g)   25.3      17.3          29.8             18.7                 45.1                    18.6                        27.8                           53.1                               18.3Tint (%)   33.0      33.4          54.7             32.5                 85.6                    29.7                        42.3                           74.2                               31.1Dmode (nm)   289      275 212             276 176                    270 252                           140 242Dst (nm)   459      443 300             492 240                    426 348                           180 310M-Ratio 1.59      1.61          1.42             1.78                 1.36                    1.58                        1.38                           1.29                               1.28Volatile content   0.4      0.3 0.3             0.3 0.4                    0.5 0.4                           0.6 0.2(%, by wt.)__________________________________________________________________________ 
    
     These carbon blacks and four control carbon blacks were utilized in the following examples. The four control carbon blacks utilized, A-D, had the analytical properties shown below in Table 5: 
     
                       TABLE 5______________________________________Control Carbon Black Analytical PropertiesControl     A       B          C     D______________________________________Type        GPF     FEF        Thermal                                SRFI.sub.2 No. (mg/g)       35.4    40.0       8.2   29.9DBP (cc/100 g)       91.0    111.7      37.5  68.5CTAB (m.sup.2 /g)       35.9    44.3       9.9   30.1Tint (%)    57.8    64.6       21.7  51.6Dmode (nm)  206     144        416   256Dst (nm)    220     186        492   288M-Ratio     1.07    1.29       1.18  1.12______________________________________ GPF = general purpose furnace FEF = fast extruding furnace Thermal = carbon black produced by a thermal process SRF = semi reinforcing furnace 
    
     EXAMPLE 10 
     The carbon blacks of the present invention produced in example runs 1-9 were incorporated into EPDM (ethylene-propylene diene polymethylene) compositions and compared to EPDM compositions incorporating the four control carbon blacks. The EPDM compositions were prepared utilizing each of the carbon black samples in an mount of 200 parts by weight in the EPDM Composition Formulation shown below in Table 6. 
     
                       TABLE 6______________________________________EPDM COMPOSITION FORMULATIONINGREDIENT     Part by weight______________________________________EPDM           100Carbon Black   200Sunpar 2280 Oil          100Zinc Oxide     5Stearic Acid   1TMTDS          2.7Butyl Zimate   2.7Methyl Zimate  2.7Sulfur         0.5Sulfasan R     1.7______________________________________ EPDM -- EXXON VISTALON ® 5600, manufactured and sold by EXXON Corporation, Houston, Texas; Sunpar 2280 -- A trademarked oil manufactured and sold by Sun Oil Company TMTDS -- tetramethylthiuram disulfide; Butyl Zimate -- a trademarked zinc dibutyldithiocarbamate manufactured an sold by R. T. Vanderbilt Co.; Methyl Zimate -- a trademarked zinc dimethyldithiocarbamate manufactured and sold by R. T. Vanderbilt Co.; Sulfasan R -- a trademarked 4,4dithiodimorpholine, manufactured and sold by Monsanto, Co., St. Louis, Missouri. 
    
     The EPDM compositions were produced as follows. 
     A Banbury BR mixer was started and maintained at a temperature of 45° C. and a rotor speed of 77 RPM. EPDM was added to the mixer and mixed for approximately 30 seconds. The Sunpar 2280 oil, zinc oxide and stearic acid, were added to the EPDM and mixed for approximately 2 additional minutes. The carbon black was added to the mixture and the temperature of the mixing chamber was cooled and maintained at a temperature of below approximately 135° C. The carbon black containing EPDM mixture was mixed for approximately 41/2 minutes and then the curing agents, TMTDS, Butyl Zimate, Methyl Zimate, Sulfur and Sulfasan R, were added to the mixture. The resulting mixture was mixed for approximately 11/2 minutes while the temperature was maintained at below approximately 135° C. The batch composition was then discharged from the mixer and analyzed by the techniques described herein. 
     The EPDM compositions produced using the carbon blacks of the present invention produced in runs 1-9 described herein had the performance characteristics set forth below in Table 7. 
     The EPDM compositions incorporating the control carbon blacks A-D were also evaluated according to the procedures described herein. The results are set forth in Tables 8-13 below, where comparisons between EPDM compositions containing carbon blacks of the present invention and EPDM compositions containing the most appropriate control carbon black are made. 
     
                                           TABLE 7__________________________________________________________________________Comparison of EPDM Composition PerformanceExample No.  1   2   3   4   5   6   7   8   9__________________________________________________________________________Carbon BlackAnalytical Properties:Iodine Number (mg/g)        22.1            16.5                28.0                    16.3                        40.7                            15.8                                28.7                                    57.9                                        16.5DBP (cc/l00 g)        132.5            39.1                35.8                    84.6                        43.1                            46.9                                119.5                                    95.8                                        30.0CTAB (m.sup.2 /g)        25.3            17.3                29.8                    18.7                        18.8                            27.8                                53.1                                    18.3                                        18.3Tint (%)     33.0            33.4                54.7                    32.5                        85.6                            29.7                                42.3                                    74.2                                        31.1Mode Stokes Diameter (nm)        289 275 212 276 176 270 252 140 242Median Stokes Diam. (nm)        459 443 300 492 240 426 348 180 310M-Ratio      1.59            1.61                1.42                    1.78                        1.36                            1.58                                1.38                                    1.29                                        1.28(Median/Mode Stokes)Volatile Content        0.4 0.3 0.3 0.3 0.4 0.5 0.4 0.6 0.2(%, by weight)EPDM CompositionPerformance at 200 phr:Viscosity (Pa · S)@ 10 sec.sup.-1        16300            10000                10900                    18000                        14100                            11300                                22900                                    23700                                        9300Viscosity (Pa · S)@ 150 sec.sup.-1        2600            1520                1590                    1920                        1720                            1600                                2790                                    3130                                        1310Mixing Energy (MJ/m.sup.3)        1300            797 876 1110                        943 839 1348                                    1571                                        687Extrusion Rate (g/min)        37.0            38.6                42.3                    40.0                        34.8                            35.9                                47.1                                    50.6                                        41.6Extrusion Shrinkage (%)        12.5            40.3                43.0                    21.7                        41.1                            32.5                                13.8                                    12.5                                        45.5t&#39;90 (min)   8.23            11.6                11.9                    9.7 9.6 11.0                                10.5                                    9.9 13.7ΔL (g · m)        238 190 206 272 271 193 308 218 164Hardness (Shore A)        79  58  65  69  65  61  76  79  50E100 (10.sup.4 × N/m.sup.2)        662 223 175 392 192 298 540 628 112Tensile (10.sup.4 × N/m.sup.2)        1069            1027                974 925 1009                            871 929 1268                                        740Elong. at Break. (%)        243 564 623 389 595 439 232 237 724Rebound (%)  39  52.0                43.7                    47.4                        34.2                            52.4                                40.0                                    30.5                                        51.8Compression Set (%)        55  34  50  52  65  31  54  58  51(70 hrs, 150° C.)Resistivity (Ω · cm) @25° C.        72  --  --  106 208 --  24  --  --Resistivity (Ω · cm) @90° C.        127 --  --  153 178 --  43  --  --__________________________________________________________________________ -- = not evaluated 
    
     
                       TABLE 8______________________________________Comparison of EPDM Composition Performance.Example No.       1        7        Control B______________________________________Carbon Black Analytical Properties:Iodine Number (mg/g)             22.1     28.7     40.0DBP (cc/100 g)    132.5    119.5    111.7CTAB (m.sup.2 /g) 25.3     27.8     44.3Tint (%)          33.0     42.3     64.6Mode Stokes Diameter (nm)             289      252      144Median Stokes Diameter (nm)             459      348      186M-Ratio (Median/Mode Stokes)             1.59     1.38     1.29Volatile Content (%, by weight)             0.4      0.4      --EPDM CompositionPerformance at 200 phr:Viscosity (Pa · S) @ 10 sec.sup.-1             16300    22900    30700Viscosity (Pa · S) @ 150 sec.sup.-1             2600     2790     3450Mixing Energy (MJ/m.sup.3)             1300     1348     1561Extrusion Rate (g/min)             37.0     47.1     44.7Extrusion Shrinkage (%)             12.5     13.8     18.2t&#39;90 (min)        8.23     10.5     7.45ΔL (g · m)             238      308      293Hardness (Shore A)             79       76       82E100 (10.sup.4 × N/m.sup.2)             662      540      650Tensile (10.sup.4 × N/m.sup.2)             1069     929      1103Elong. at Break. (%)             243      232      184Rebound (%)       39       40.0     31.0Compression Set (%)             55       54       57(70 hrs, 150° C.)Resistivity (Ω · cm) @ 25° C.             72       24       43Resistivity (Ω · cm) @ 90° C.             127      43       69______________________________________ -- = not evaluated 
    
     The results set forth in Table 8 indicate that at a carbon black level of 200 phr the EPDM compositions incorporating the carbon blacks of the present invention have lower viscosity and lower mixing energy. Therefore the EPDM compositions incorporating the carbon blacks of the present invention exhibit better processing characteristics than the EPDM compositions incorporating the control carbon blacks. 
     
                       TABLE 9______________________________________Comparison of EPDM Composition PerformanceExample No.           1        Control B______________________________________Carbon Black Analytical Properties:Iodine Number (mg/g)  22.1     40.0DBP (cc/100 g)        132.5    111.7CTAB (m.sup.2 /g)     25.3     44.3Tint (%)              33.0     64.6Mode Stokes Dia. (nm) 289      144Median Stokes Dia. (nm)                 459      186M-Ratio (Median/Mode Stokes)                 1.59     1.29Volatile Content (%, by weight)                 0.4      --EPDM Composition Performance at 150 phr:Viscosity (Pa · S) @ 10 sec.sup.1                 12500    22200Viscosity (Pa · S) @ 150 sec.sup.1                 1900     1940Mixing Energy (MJ/m.sup.3)                 1010     1222Extrusion Rate (g/min)                 39       37.4Extrusion Shrinkage (%)                 17.2     19.8t&#39;90 (min)            9.25     8.33ΔL (g · m)                 200      249Hardness (Shore A)    69       71E100 (10.sup.4 × N/m.sup.2)                 407      376Tensile (10.sup.4 × N/m.sup.2)                 1145     1179Elong. at Break (%)   436      370Rebound (%)           46.1     35.8Compression Set (%)(70 hrs, 150° C.)                 57       57Resistivity (Ω · cm) @ 25° C.                 400      88Resistivity (Ω · cm) @ 90° C.                 640      118______________________________________ -- = not evaluated 
    
     The results set forth in Table 9 show the advantage of utilizing a carbon black of the present invention in an EPDM composition for an application where resistivity is a critical requirement. As shown in the table, at 150 phr loading, which is typical for a cooling hose application, the EPDM composition incorporating the carbon black of the present invention exhibits a higher resistivity than the EPDM composition incorporating the control carbon black. 
     Additionally, the EPDM composition incorporating the carbon black of the present invention has lower viscosity and lower mixing energy than the EPDM composition incorporating the control carbon black. This indicates that EPDM compositions incorporating the carbon black of the present invention will have improved processibility in comparison with EPDM compositions incorporating the control carbon black. 
     
                       TABLE 10______________________________________Comparison of EPDM Composition PerformanceExample No.     6       2       9     Control C______________________________________Carbon BlackAnalytical Properties:Iodine Number (mg/g)           15.8    16.5    16.5  8.2DBP (cc/100 g)  46.9    39.1    30.0  37.5CTAB (m.sup.2 /g)           18.6    17.3    18.3  9.9Tint (%)        29.7    33.4    31.1  21.7Modes Stokes Dia. (nm)           270     275     242   416Median Stokes Dia. (nm)           426     443     310   492M-Ratio (Median/Mode Stokes)           1.58    1.61    1.28  1.18Volatile Content (%, by weight)           0.5     0.3     0.2   --EPDM CompositionPerformance at 200 phr:Viscosity (Pa·) @ 10 sec.sup.1           11300   10000   9300  10400Viscosity (Pa·) @ 150 sec.sup.1           1600    1520    1310  1490Mixing Energy (MJ/m.sup.3)           839     797     687   799Extrusion Rate (g/min)           35.9    38.6    41.6  32.0Extrusion Shrinkage (%)           32.5    40.3    45.5  43.5t&#39;90 (min)      11.0    11.6    13.7  13.2ΔL (g · m)           193     190     164   220Hardness (Shore A)           61      58      50    53E100 (10.sup.4 × N/m.sup.2)           298     223     112   109Tensile (10.sup.4 × N/m.sup.2)           871     1027    740   933Elong. at Break (%)           439     564     724   794Rebound (%)     52.4    52.0    51.8  55.0Compression Set (%)           31      34      51    54(70 hrs, 150° C.)______________________________________ -- not evaluated 
    
     The results set forth in Table 10 indicate that the carbon blacks of the present invention provide improved reinforcement and processing properties for EPDM compositions when compared to thermal carbon blacks. Thus the carbon blacks of the present invention advantageously provide furnace carbon black replacements for thermal carbon blacks or carbon black blends containing thermal carbon blacks. 
     
                       TABLE 11______________________________________Comparison of EPDM Composition Performance                              Control                                    ControlExample No.  3       4       5     C     D______________________________________Carbon BlackAnalytical Properties:Iodine Number (mg/g)        28.0    16.3    40.7  8.2   29.9DBP (cc/100 g)        35.8    84.6    43.1  37.5  68.5CTAB (m.sup.2 g)        29.8    18.7    45.1  9.9   30.1Tint (%)     54.7    32.5    85.6  21.7  51.6Mode Stokes Dia. (nm)        212     276     176   416   256Median Stokes Dia. (nm)        300     492     240   492   288M-Ratio      1.42    1.78    1.36  1.18  1.12(Median/Mode Stokes)Volatile Content        0.3     0.3     0.4   --    --(%, by weight)EPDM CompositionPerformance at 200 phr:Viscosity    10900   18000   14100 10400 16600(Pa · S) @ 10 sec.sup.1Viscosity    1590    1920    1720  1490  1880(Pa·) @ 150 sec.sup.1Mixing Energy (MJ/m.sup.3)        876     1110    943   799   1091Extrusion Rate (g/min)        42.3    40.0    34.8  32.0  36.8Extrusion Shrinkage (%)        43.0    21.7    41.1  43.5  23.8t&#39;90 (min)   11.9    9.7     9.6   13.2  11.2ΔL (g · m)        206     272     271   220   270Hardness (Shore A)        65      69      65    53    69E100 (10.sup.4 × N/m.sup.2)        175     392     192   109   338Tensile (10.sup.4 × N/m.sup.2)        974     925     1009  933   989Elong. at Break (%)        623     389     595   794   421Rebound (%)  43.7    47.4    34.2  55.0  40.6Compression Set (%)        50      52      65    54    57(70 hrs, 150° C.)______________________________________ -- not evaluated 
    
     The results set forth in Table 11 indicate that the carbon blacks of the present invention can replace the use of blends of thermal and SRF type carbon blacks to provide a satisfactory degree of performance characteristics. EPDM compositions incorporating the carbon black of Example 5 also yield profiles having textured matte finishes when extruded or shaped. 
     
                       TABLE 12______________________________________Comparison of EPDM Composition PerformanceExample No.       8        Control A                               Control B______________________________________Carbon Black Analytical Properties:Iodine Number (mg/g)             57.9     35.4     40.0DBP (cc/100 g)    95.8     91.0     111.7CTAB (m.sup.2 /g) 53.1     35.9     44.3Tint (%)          74.2     57.8     64.6Mode Stokes Dia. (nm)             140      206      144Median Stokes Dia. (nm)             180      220      186M-Ratio (Median/Mode Stokes)             1.29     1.07     1.29Volatiles (%, by weight)             0.6      --       --EPDM CompositionPerformance at 200 phr:Viscosity (Pa · S) @ 10 sec.sup.1             23700    24000    30700Viscosity (Pa · S) @ 150 sec.sup.1             3130     2850     3450Mixing Energy (MJ/m.sup.3)             1581     1252     1561Extrusion Rate (g/min)             50.6     41.1     44.7Extrusion Shrinkage (%)             12.5     15.9     18.2t&#39;90 (min)        9.9      7.41     7.45ΔL (g · m)             218      299      293Hardness (Shore A)             79       75       82E100 (10.sup.4 × N/m.sup.2)             628      493      650Tensile (10.sup.4 × N/m.sup.2)             1268     1030     1103Elong. at Break (%)             237      288      184Rebound (%)       30.5     34.5     31.0Compression Set (%)             58       50       57(70 hrs, 150° C.)______________________________________ -- not evaluated 
    
     The results set forth in Table 12 indicate that the EPDM composition incorporating the carbon black of the present invention has a higher extrusion rate than the EPDM compositions incorporating the control carbon black. Thus, EPDM compositions incorporating the carbon blacks of the present invention may be extruded at higher throughputs than EPDM compositions incorporating the control carbon blacks. 
     The EPDM composition incorporating the carbon black of the present invention also has a lower extrusion shrinkage and therefore will have better dimensional control during the extrusion operation than the EPDM compositions incorporating the control carbon blacks. 
     These results also indicate that the EPDM composition incorporating the carbon black of the present invention has good overall physical properties. Additionally, the carbon blacks of the present invention have a unique combination of surface area and structure that results in the carbon blacks being useful in preparing EPDM compositions that are to be UHF cured. 
     It should be clearly understood that the forms of the present invention herein described are illustrative only and are not intended to limit the scope of the invention.