AU3126199A - Carbon black compositions and improved polymer compositions - Google Patents

Description

I r/vu/v i i Regulation 3.2(2)

AUSTRALIA

Patents Act 1990

ORIGINAL

COMPLETE SPECIFICATION STANDARD PATENT 4**46.

4.

*4 4 *4 04 4*4444 4 44 *4 4 4 U 4 44 4 .4 S. 4. 4 444 4 44.. 4 4* 4 U 44 *4 Application Number: Lodged: Invention Title: CARBON BLACK COMPOSITIONS AND IMPROVED POLYMER

COMPOSITIONS

The following statement Is a full description of this Invention, Including the best method of performing It known to us IP Australia Documents received on: RiAY 1999 Baton No: r CARBON BLACK COMPOSITIONS AND IMPROVED POLYMER

COMPOSITIONS

Field of the Invention The present invention relates to carbon black compositions comprising polyethers. The compositions may be produced by incorporating polyethers onto fluffy carbon black in a pelletizing process to produce free flowing, low dust, attrition resistant carbon black pellets which are easily dispersible in most polymeric systems and provide enhanced rheological and mechanical properties.

The present invention also relates to polymer compositions which o incorporate the carbon black compositions of the present invention.

Background of the Art Carbon blacks produced by a furnace process generally have bulk densities ranging from 0.02 to 0.1 gram/cubic centimeter (g/cc) and are generally known as fluffy carbon blacks. Fluffy carbon blacks are generally easy to disperse in liquids, and in some polymeric systems. However, fluffy carbon blacks are generally cohesive and, hence difficult to handle for purposes such as conveying and weighing.

Fluffy carbon blacks are agglomerated by various types of mechanical processes, either in the dry state, or with the aid of a liquid to produce pellets with improved handling characteristics. Common liquid pelletizing agents are oil and water. The process of agglomerating fluffy carbon blacks to form carbon black pellets is generally referred to as pelletizing.

Unfortunately, generally utilized densification or agglomeration (pelletizing) processes have detrimental effects on the dispersion characteristics of the carbon black. Therefore it is recognized in the art that in pelletizing carbon blacks there is a fine balance between acceptable handling characteristics and ease of dispersion.

A process for pelletizing carbon black is disclosed in U.S. Patent No.

2,065,371 which describes a typical wet pelletization process whereby the fluffy carbon black and a liquid, typically water, are combined and agitated until spherical beads are formed. These beads are then dried to reduce the water content preferably to below 1% to form carbon black pellets.

Prior art patents also disclose the use of binder additives in a wet pelletization process to further improve the pellet handling characteristics.

U.S. Patent No. 2,850,403 discloses the use of carbohydrates e.g. sugar, molasses, soluble starches, saccharides and lignin derivatives as pellet binders in the range of 0.1% to by weight, based on the dry carbon black. The preferred drying temperature of the wet pellet is disclosed as 150 to 4250 C which together with the residence time is sufficient to carbonize the binder.

U.S. Patent No. 2,908,586 discloses the use of a rosin emulsion as pellet binders as an alternative to carbohydrates. The preferred level of rosin binder is in the range 0.5% to by weight, based on the dry carbon black.

U.S. Patent No. 2,639,225 discloses the use of sulphonate and sulphate anionic surfactants as pellet binders at levels of 0.1% to by weight, based on the dry carbon black.

U.S. Patent No. 3,565,658 discloses the use of a fatty amine ethoxylate nonionic surfactant where the level of ethoxylation ranges from 2 to 50 moles of ethylene oxide per fatty amine group. The preferred level of surfactant in the pelletizing water is in the range 0.05% to by weight, based on the dry carbon black.

Similarly, U.S. Patent No. 3,645,765 discloses the use of a fatty acid or rosin acid ethoxylate, non-ionic surfactant where the level of ethoxylation is 5 to moles ethylene per acid group. The preferred level of addition on the carbon black is in the range 0.1% to 10%, by weight, based on the dry carbon black.

Soviet Union Patent No. 937,492 claims the benefits of using 0.1% to by weight, based on the dry carbon black, of an aqueous solution of a reaction product generated from urea and an ethoxylated alkylolamide. The preferred level of ethoxylation is 1 to 7 moles of ethylene oxide per alkylolamide molecule.

U.S. Patent No. 3,844,809 discloses the reduction in pellet dust levels by incorporating 0.4% to by weight, based on the dry carbon black of an aqueous solution containing 0.001% to by weight, of a nonionic surfactant containing randomly repeating poly(ethylene oxide) and poly (dimethyl silicone) groups. Molasses is also included at substantially higher concentration (up to by weight) as a co-binder and nitric acid (up to 15%, by weight) as an oxidizing source.

The use of carbohydrates, rosin or surface active agents as disclosed in the above patents is focused towards improving pellet handling qualities. The patents do not disclose that the pelletizing treatments affected the performance properties of the carbon black in the final product applications, which are typically rubber orientated.

Japanese Patent No. 1,201,369 discloses the use of a carboxylic acid type amphoteric surfactant in a concentration range 0.001% to by weight, i in the pelletizing water to produce carbon black pellets with low adhesion and excellent dispersibility.

U.S. Patent No. 3,014,810 discloses the benefits of wet pelletizing a range of pigments, including carbon blacks, with a blend of a quaternary 0 0ammonium compound and a bis(-2-hydroxyethyl)alkyl amine. Improvements in dispersion rate, viscosity stability and antistatic properties are disclosed for the blend of surface active agents.

Pelletizing with oil, in the presence and absence of water is disclosed in U.S. Patent No. 2,635,057, U.S. Patent No. 3,011,902 and U.S. Patent No.

S elt4,102,967 as beneficial in improving the handling properties of carbon black 0 pellets.

Several patents, including U.S. Patent No. 2,511,901, U.S. Patent No.

2,457,962, U.S. Patent No. 4,440,807, U.S. Patent No. 4,569,834, U.S. Patent No. 5,168,012 and Japanese Patent No. 77,130,481 disclose polymers in emulsion, organic solvent solutions and in molten form as means of modifying the pellet properties of carbon black.

U.S. Patent No. 4,277,288 discloses a fluidised granulation process for producing free-flowing dustless pigment granules in the absence of water. The organic component required to produce a dustless granule consists of two components, 5-20 phr of a non-aqueous granulating aid and a non-ionic surfactant for example sorbitan oleate ethoxylate as a second component. The bulk of the disclosure relates to producing freeflowing organic and inorganic pigments, including carbon black.

U.S. Patent No. 4,397,652 also discloses a process for producing negligible dust preparations of organic dyes and optical brighteners. The process involves the dry blending, between 30 and 800 C, of the dye, or optical brightener, with 2-10%, by weight, of an adhesive selected from the group consisting of polyhydric alcohol sorbitol); manitol; manitose; lactose; hydrated dextrose; neopentyl glycol; and polyethylene glycol with a molar mass above 3,000. Also included in the composition is 1-10% of a dusting aid selected from the group consisting of fatty acid ethanolamide; fatty acid amide; S.alkyl alcohol; substituted phenol; and polyethylene glycol with a molar mass between 200 and 1000.

U.S. Patent No. 4,230,501 discloses a pigment concentrate, dispersible in plastics, which is prepared by combining 51-85%, by weight, of a pigment and 14-49%, by weight, of a waxy component. The waxy component is disclosed as e being predominantly a natural, petroleum or synthetic wax which has been blended with either polyethylene glycol or a hydrocarbon resin to reduce the melt viscosity and allow better incorporation of the pigments :::Polyethylene glycol is previously known as an additive for direct compounding into thermoplastic compositions.

U.S. Patent No. 4,013,622 discloses the incorporation of 100 to 600 ppm of polyethylene glycol in the molar mass range of 600 to 20,000 (preferably 1300 to 7500) to reduce the breakdown of polyethylene during blown film operations which is observed as gel formation.

U.S. Patent No. 4,812,505, U.S. Patent No. 4,440,671 and U.S. Patent No. 4,305,849 disclose the use of polyethylene glycols in the molar mass range 1,000 to 20,000 as beneficial for reducing the heat and water-treeing characteristics in polyolefin compositions for electrical insulation. Similarly U.S.

Patent No. 4,612,139 extends this concept of water-tree reduction to include the polyethylene glycol in semiconductive polyolefin compositions containing carbon black.

Similar compositions are claimed in German Patent DE 27 23 488 where polyethylene glycol and other mobile additives are disclosed as being beneficial to reduce the interlaminar adhesion between the insulation layer and outer conductive layer in an electric cable construction. Polyethylene glycol and branched ethoxylate molecules are disclosed as plasticisers for ethylene-acrylic acid copolymers in U.S. Patent No. 3,361,702.

United Kingdom Patent GB 975,847 discloses the use of polyethylene glycol, or an aliphatic derivative, in an aqueous solution as a means of producing agglomerates of organic rubber chemicals. A dough is formed as an intermediate which is then converted into pellets and dried at low temperatures.

Summary of the Invention ••ee The present invention comprises carbon black compositions that in their dry form have improved handling characteristics and that impart enhanced performance characteristics to polymer compositions. The carbon black compositions comprise: carbon black and S"0.1% to 50%, preferably 1 to 20%, by weight, of at least one binder which is a polyether.

Preferably the polyether is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

It is also preferred that the polyether binder have an HLB value of 8.0 to HLB value refers to hydrophile-lipophile balance value which may be determined by the method described in Non-ionic Surfactants Volume 23, edited by Martin Schick (Marcel Dekker Inc. (New York) 1987; ISBN 0-8247- 7530-9), page 440. Non-ionic Surfactants Volume 23 provides equations relating the structure of the surfactant molecule to HLB value. HLB value is also discussed in the following journal articles: Griffin J. Soc. Cosmetic Chemist, Vol. 1, page 311 et seq. (1949) and Vol. 5, page 249 et seq. (1954).

From data relating to the weight percentage of ethylene oxide in the molecule, saponification number of the ester linkage and acid value of the "fatty" acid, HLB value may be directly calculated from one of the following equations: for polyhydric fatty acid esters: HLB 20 where S saponification number of the ester and A acid number of the acid; and for ethoxylated polyhydric alcohols: HLB (E where E weight of percent ethylene oxide and P weight pigment of polyhydric alcohol.

While any carbon black may be utilized in the compositions of the present invention, preferably the carbon black component of the carbon black composition has a nitrogen surface area (N 2 SA) of 15 to 1800 m 2 a fluffy dibutyl phthalate absorption value (DBP) of 50 to 350 cc/100g and a cetyl trimethylammonium bromide absorption value (CTAB) of 15 to 1500 m 2 /g.

The carbon black compositions may be produced in any manner known 0 in the art, such as by physically blending the components, melt mixing the components or combining the components while pelletizing the carbon black.

Preferably the carbon black compositions are obtained by pretreating the carbon black with the binder.

The carbon black compositions may also be produced by a pelletizing process by: contacting a fluffy carbon black in a pin pelletizer with an aqueous 0 solution containing a binder selected from the foregoing groups of compounds wherein the preferred level of binder in the pelletizing water is from 0.5% to 50%; more preferably 20-40%, by weight; and S"heating the wet pellets under controlled temperature and time parameters such that the water is removed from the pellets but the binder does not undergo substantial decomposition, and the final binder level on the dry carbon black is from 0.1%to The present invention also includes new polymer compositions comprising: a polymer component and 0.1-65%, preferably 0.1-20%, by weight, of a composition comprising a carbon black and 0.1-50%, preferably 1-20%, of at least one polyether binder component. Preferably, the carbon black is pretreated with the binder component. The preferred carbon blacks, and binder components are as set forth above with respect to the carbon black compositions of the present invention. The polymer compositions may include other conventional additives such as pigments, reinforcing agents and the like.

While any polymer may be utilized in the polymer composition of the present invention, preferred polymers for use in the polymer compositions of the present invention include, but are not limited to: a) homo or copolymers and graft polymers of ethylene where the comonomers are selected from butene, hexene, propene, octene, vinyl acetate, acrylic acid, methacrylic acid, esters of acrylic acid, esters of methacrylic acid, maleic anhydride, half ester of maleic anhydride, and carbon monoxide; b) elastomers selected from natural rubber, polybutadiene, polyisoprene, random styrene butadiene rubber (SBR), polychloroprene, acrylonitrile butadiene, ethylene propylene co and terpolymers; c) homo and copolymers of styrene, including styrene butadiene styrene linear and radial polymer, acrylonitrile butadiene styrene (ABS) and styrene acrylonitrile (SAN); d) linear and branched polyether or polyester polyols; e) crystalline and amorphous polyesters and polyamides; S. f) alkyd resins, rosin acids or rosin esters, hydrocarbon resins produced from thermal or Friedel Crafts polymerization of cyclic diene monomers such as dicyclopentadiene, indene, cumene; and g) hydrocarbon oils such as parafinnic oil, naphthenic oil and hydrogenated naphthenic oil.

The polymer compositions of the present invention may be produced in any manner known to the art for combining polymers and dry or aqueous components.

The present invention further includes articles of manufacture produced from the polymer compositions of the present invention.

For use in semiconductive wire and cable applications, a typical formulation of the present invention preferably comprises: 25-55%, by weight, of a composition comprising carbon black and 0.5 to parts per 100 parts of carbon black of at least one polyether binder component; 0 to by weight a stabilizer or antioxidant 0 to by weight an organic peroxide, preferably dicumyl peroxide; 0 to 10%, by weight a vinyl silane; the remainder being a polymer, or a blend of polymers, selected from the following group: ethylene homopolymer; ethylene copolymerized with one or more alpha olefins, such as propylene, butene, or hexene; ethylene copolymerized with propylene and a diene monomer, preferably norbomene; and ethylene copolymer with one or more monomers selected from vinyl acetate, acrylic acid, methacrylic acid, esters of acrylic or methacrylic acid containing 1 to 8 carbon atoms, maleic anhydride or a monoester derived from fumaric or maleic acid, vinyl chloride or vinylidene chloride.

The curable semi-conductive composition of the present invention may additionally include an additive polymer such as acrylonitrile butadiene elastomer containing 25-55%, by weight acrylonitrile.

For use as a masterbatch composition, a typical formulation of the present invention preferably comprises: 30-60%, by weight, of a composition comprising a carbon black and 0.1 to 50%, preferably 1-20%, of at least one binder component; and 70-40%, by weight of an ethylene homopolymer or copolymer, where the comonomer is preferably selected from hexene, propene, butene, octene or vinyl acetate. Preferably, the polymer composition is polyethylene, low density polyethylene, linear low density polyethylene, high density polyethylene or a polyethylene wax. The masterbatch composition may additionally include antioxidants, peroxide decomposers, hindered amine light stabilizers, substituted benzophenone UV adsorbers or process aids.

An advantage of the carbon black compositions of the present invention is that in dry form the carbon black compositions of the present invention have improved handling properties in comparison with conventional fluffy or pelleted carbon blacks.

An advantage of the polymer compositions of the present invention is that the polymer compositions exhibit enhanced rheological, processing or mechanical properties.

Further advantages of the carbon black compositions, and the polymer compositions, of the present invention will become apparent from the following detailed description.

Detailed Description of the invention The present invention includes carbon black compositions which in dry form have improved handling characteristics and impart enhanced performance characteristics to polymer compositions.

-Osf: The carbon black compositions comprise: carbon black and 0. 1% to 50%, preferably 1 to 20%, by weight, of at least one binder which is a polyether and preferably is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

It is also preferred that the at least one binder have an HLB value of 8.0 to HLB value may be determined in the manner set forth above.

While any carbon black may be utilized in the compositions of the present invention, preferably the carbon black component of the carbon black composition has a nitrogen surface area (N 2 SA) of 15 to 1800 m 2 a fluffy S"dibutyl phthalate absorption value (DBP) of 50 to 350 cc/100g and a cetyl triamethylammonium bromide absorption value (CTAB) of 15 to 1500 m 2 /g.

The carbon black compositions may be produced by any conventional technique for combining carbon black with dry or aqueous components.

Preferably the carbon black compositions are produced by pretreating the carbon black with the binder. The carbon black compositions may be produced, in dry form, by a conventional pelletizing process. For example, the carbon black compositions of the present invention may be produced by contacting a fluffy carbon black in a pin pelletizer with an aqueous solution containing a binder selected from the foregoing groups of compounds wherein the level of binder in the pelletizing water is from 0.5% to 50%; and heating the wet pellets under controlled temperature and time parameters such that the water is removed from the pellets but the binder does not undergo substantial decomposition, and the final binder level on the dry carbon black is from 0.1% to The preparation of aqueous solutions containing the binder compositions used in the present invention is within the skill of one of ordinary skill in the art.

Pin pelletizers which may be utilized to produce the compositions of the present invention are known in the art and include the pin pelletizer described in U.S. Patent No. 3,528,785, the disclosure of which is hereby incorporated by reference. U.S. Patent No. 3,528,785 also describes a conventional pelletizing process which may be utilized to produce the compositions of the present invention.

The present invention also includes new polymer compositions comprising: a polymer component and 0.1-65%, preferably 0.1-20%, by weight, of a S 15 composition comprising a carbon black and 0.1-50%, preferably 1-20%, of at least one binder which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

Preferably, the carbon black is pretreated with the binder component. The preferred carbon blacks, and binder components are as set forth above with 20 respect to the carbon black compositions of the present invention. For example, it is preferred that the binder component have an HLB value of 8.0 to 30. The polymer compositions may include other conventional additives such as pigments, reinforcing agents and the like.

While any polymer may be utilized in the polymer composition of the present invention, preferred polymers for use in the polymer compositions of the present invention include, but are not limited to: a) homo or copolymers and graft polymers of ethylene where the comonomers are selected from butene, hexene, propene, octene, vinyl acetate, acrylic acid, methacrylic acid, esters of acrylic acid, esters of methacrylic acid, maleic anhydride, half ester of maleic anhydride, and carbon monoxide; 11 b) elastomers selected from natural rubber, polybutadiene, polyisoprene, random styrene butadiene rubber (SBR), polychloroprene, acrylonitrile butadiene, ethylene propylene co and terpolymers; c) homo and copolymers of styrene, including styrene butadiene styrene linear and radial polymer, acrylonitrile butadiene styrene (ABS) and styrene acrylonitrile (SAN); d) linear and branched polyether or polyester polyols; e) crystalline and amorphous polyesters and polyamides; f) alkyd resins, rosin acids or rosin esters, hydrocarbon resins 10 produced from thermal or Friedel Crafts polymerization of cyclic diene monomers such as dicyclopentadiene, indene, cumene; and g) hydrocarbon oils such as parafinic oil, naphthenic oil and hydrogenated naphthenic oil.

The polymer compositions of the present invention may be produced in 15 any manner known to the art for combining polymers and dry or aqueous components.

The present invention further includes articles of manufacture produced from the polymer compositions of the present invention.

For use in semiconductive wire and cable applications, a typical 20 formulation of the present invention comprises: 25-55%, by weight, of a composition comprising a carbon black and to 10 parts, per 100 parts of carbon black, of at least one binder which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer; 0 to by weight a stabilizer or antioxidant; 0 to by weight an organic peroxide, preferably dicumyl peroxide; 0 to 10%, by weight a vinyl silane; the remainder being a polymer, or a blend of polymers, selected from the following group: ethylene homopolymer; ethylene copolymerized with one or more alpha olefins, such as propylene, butene, or hexene; 12 ethylene copolymerized with propylene and a diene monomer, preferably norbornene; and ethylene copolymer with one or more monomers selected from vinyl acetate, acrylic acid, methacrylic acid, esters of acrylic or methacrylic acid containing 1 to 8 carbon atoms, maleic anhydride or a monoester derived from fumaric or maleic acid, vinyl chloride or vinylidene chloride.

The curable semi-conductive composition of the present invention may additionally include an additive polymer such as acrylonitrile butadiene elastomer containing 25-55%, by weight acrylonitrile.

10 For use as a masterbatch composition, a typical formulation of the present invention preferably comprises: 70-40%, by weight of an ethylene homopolymer or copolymer, where the comonomer is preferably selected from hexene, propene, butene, octene or vinyl acetate; and S 15 30-60%, by weight, of a composition comprising a carbon black and 0.1 to 50%, preferably 1-20%, a binder component which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

Preferably, the polymer composition is polyethylene, low density polyethylene, linear low density polyethylene, high density polyethylene or a 20 polyethylene wax. The masterbatch composition may additionally include antioxidants, peroxide decomposers, hindered amine light stabilizers, substituted benzophenone UV adsorbers or process aids.

The effectiveness and advantages of various aspects and embodiments of the present invention will be further illustrated by the following examples wherein the following testing procedures were utilized.

The following testing procedures were utilized in the determination and evaluation of the analytical properties of the carbon blacks utilized in the following examples. The DBP (dibutyl phthalate adsorption value) of the carbon blacks utilized in the examples, expressed as cubic centimeters DBP per 100 grams carbon black (cc/100g), was determined according to the procedure set 13 forth in ASTM D2414. The nitrogen surface area (N 2 SA) of the carbon blacks utilized in the examples, expressed as square meters per gram (m 2 was determined according to ASTM test procedure D3037 Method A.

The carbon blacks pellets described in the following examples were evaluated utilizing the following testing procedures. The pellets were assessed for mass pellet strength using ASTM D1937. Pellet attrition was evaluated using a modified version of ASTM D 4324, wherein the ASTM test procedure was modified to generate the level of dust after shaking samples for 5 minutes.

The moisture content of the pellets was determined by drying the sample 10 to constant mass in an air circulating oven at 1500 C and then calculating :moisture percentage by comparing the weight prior to drying to the weight after drying.

The polymer compositions, including the polymer masterbatch compositions, described in the following examples were evaluated utilizing the following test procedures.

Melt index was determined by ASTM D 1238.

Pressure rise of the masterbatch compositions was determined by introducing a 325 mesh (47 micron hole size) screen pack behind the breaker plate of a 0.025 meter (1 inch) single screw extruder fitted with a pressure 20 transducer to measure the pressure change in the region of the screen pack.

Viscosity of the polymer compositions was measured utilizing a Carri- Med CS viscometer, produced and sold by TA Instruments of Wilmington, Delaware, at the temperature, and utilizing the shear rate specified in the particular example.

Triple roll mill passes were evaluated by passing the polymer compositions through a triple roll mill and recording the number of passes required to generate zero scratches on a Hegman gauge, and also recording the residual background "sand" value.

Dispersion of the diluted samples in the following examples was determined by diluting the masterbatch composition down to a loading of by weight, carbon black with the EVA resin in a Brabender mixer operating at 850 C and 50 rpm. The mixing time was 2 minutes. Samples were then pressed 14 between microscope slides and dispersion at 100X magnification was determined by the Cabot Corporation rating method wherein the number (1-6) refers to the size of the undispersed particles, with 1 being small and 6 being large; and the letter refers to the number of particles per field of view, with A being 1-2 particles and E being greater than 50 particles. Lower numbers and earlier letters indicate better dispersion, with a 1A rating indicating good dispersion and a 6E rating indication poor dispersion.

In Examples 18-26, dispersion of the carbon black pellets was determined by measuring the number and size of surface imperfections in the o.o: S. 10 tape formed from the compound incorporating the pellets using an optical microscope at 100x magnification and a reflected light source.

The polymer compositions were evaluated for strippability utilizing the following technique. The compositions containing 40% carbon black in the ethylene vinyl acetate resin were compounded in a Brabender mixer with 1% 15 dicumyl peroxide while maintaining the mixing temperature below 1500 C. The material was transferred to a heated hydraulic press (temperature 1300 C) and a plaque 1.2 mm thick produced. A 2 mm polyethylene plaque containing 1% dicumyl peroxide was produced in a similar manner. The two plaques were laminated together under a pressure of 7.030 kg/cm2 (100 psi) and exposed to 20 a curing cycle of 1800 C for 15 minutes. The laminate was allow to cool to S"ambient temperature under pressure. The delamination force under a peeling angle of 180 degrees and a separation speed of 0.10 meter/minute (3.94 inches/minute) was recorded; the results provided are an average of 28 peel tests.

The modulus, tensile and elongation of the polymer compositions were measured by the procedure set forth in ASTM D 412.

The Shore A Hardness of the rubber compounds was determined according to the procedure set forth in ASTM D-2240-86.

The maximum torque was determined from the peak of the motor load versus time profile from the Brabender mixer.

The dump torque (Nm) was determined from the final torque value at the end of the mixing cycle.

The total energy (Nm) was determined by calculating from the area under the full mixing curve.

The MDR 1700 C T50 and T90 was determined according to the procedure set forth in ASTM 2084.

The Mooney viscosity (ML(1+4)@1000 C was determined according to the procedure set forth in ASTM 1646.

The IRHD (hardness) was determined according to the procedure set forth in ASTM D1415.

The effectiveness and advantages of the present invention will be further 10 illustrated by the following examples.

Examples 14 Examples 1-4 illustrate the use and advantages of carbon black compositions of the present invention, in comparison to conventional carbon black pellets, in polypropylene fiber applications.

15 Four carbon black pellet compositions, A, B, C and D were produced by introducing 400 grams of a fluffy carbon black, identified herein as CB-1, .:":having a DBP of 60 cc/100g and a nitrogen surface area of 112 m 2 into a batch pin pelletizer together with a solution containing 20 g of a binder and 300 g of water. The binder utilized in each pelleting composition was as shown 20 in the Table below.

Pellet Composition Binder A water B 5% sorbitan monostearate with 20 moles ethoxylate C 5% sorbitan monooleate with 5 moles ethoxylate D 5% sorbitan monooleate with 20 moles ethoxylate Carbon black pellet composition A was a control composition, carbon black pellet compositions B, C and D were carbon black compositions of the present invention.

The carbon black/binder mixture was agitated for 5 minutes with a rotor speed of 800 rpm. The resultant pellets were dried at 1200 C until the moisture content of the pellets was below 0.51. Pellet strength of each pellet composition was assessed qualitatively. The results are set forth in Table 1 below.

16 The carbon black pellets were combined with a polypropylene homopolymer of melt index 35 in a twin screw extruder to produce a masterbatch containing 35% by weight of the pelleted carbon black, the remainder being polypropylene and binder.

The polypropylene composition was introduced into a 1 inch single screw extruder until equilibrium pressure conditions. The masterbatch was introduced and the rate of pressure change recorded according to the procedure described above. The results were as shown in Table 1 below.

Table 1 r r

S

S.

S. S S 10 Carbon Black Pellet pellet strength pressure rise Composition (kilogram/sq.cm)/g A weak 0.342 (4.86psi/g) B strong 0.305 (4.34psi/g) C strong 0.299 (4.25psi/g) D strong 0.209 (2.97psi/g) These results indicate that carbon black compositions B, C and D of the present invention have improved pellet strength in comparison with the carbon black pellet composition A produced with pelletizing water only. In addition, the reduction in pressure build-up in masterbatch compositions containing carbon black compositions B, C and D of the present invention, in comparison to the masterbatch composition containing carbon black composition A, would translate to a reduction in the frequency of screen changes on a fiber production line, and therefore improved capacity and lower operating costs for the production line.

Examples 5-10 Examples 5-10 illustrate the use and advantages of carbon black compositions of the present invention, in comparison to conventional carbon black pellets, in polypropylene fiber applications.

Two carbon black pellet compositions, E and F were produced in a continuous process by combining a fluffy carbon black, identified herein as CB- 2, having a DBP of 112 cc/100g and an nitrogen surface area of 60 m2/g into a batch pin pelletizer together with a binder solution. The pellets were produced in a continuous pin pelletizer operating with rotor speed of 800 rpm to provide wet pellets with an average water content of 50%. The wet pellets were dried in a heated rotating drum to provide dry pellets with a moisture content below 0.6%.

The binder utilized in each pelleting composition was as shown in the Table below.

Pellet Composition Binder E water F 2% sorbitan monooleate with 20 moles ethoxylate Four runs of carbon black pellet composition E, and two runs of carbon black pellet composition F were made. Carbon black pellet composition E was a control composition, and carbon black pellet compositions F was a carbon black composition of the present invention.

The pellets were assessed for mass pellet strength and pellet attrition 15 using the procedures described above. In addition, the pellets were used to produce a masterbatch, as in examples 1-4, and the pressure rise determined as described above. The results are set forth in Table 2 below.

Table 2 20 S 2 Carbon pellet strength dust pressure Black Pellet kilograms 5 min. rise Composition (kg/cm 2 )/g E run 1 6.80 (15 Ibs.) 1.2 0.773 (11.0 psi/g) E run 2 6.35 (14 Ibs.) 1.2 0.801 (11.4 psi/g) E run 3 7.26 (16 Ibs.) 2.8 0.907 (12.9 psi/g) E run 4 8.16 (18 Ibs.) 1.6 0.640 (9.1 psi/g) F run 1 19.95 (44 Ibs.) 0.4 0.513 (7.3 psi/g) F run 2 26.30(58 Ibs.) 0.2 0.372 (5.3 psi/g) These results illustrate the significant improvement in pellet strength and attrition resistance by incorporation of a binder of the type utilized in the present invention during the pelletizing process in preparing the carbon black pellet composition F of the present invention. Carbon black pellet composition F of the present invention also has improved dispersion, in comparison with a 18 conventional water pelletized carbon black pellet composition E, as seen by the reduction in pressure build-up when extruded through a screen pack which would translate to improved output at lower operating cost.

Examples 11-14 Examples 11-14 illustrate the advantages of the carbon black pellet compositions of the present invention for use in polyurethane applications.

Two fluffy carbon blacks, identified herein as CB-3 and CB4, were pelletized to produce carbon black pellet compositions. Carbon blacks CB-3 and CB-4 had the combination of analytical properties set forth below: 10 Fluffy Carbon Black DBP NSA CB-3 112 cc/100g 58 m 2 /g CB-4 140 cc/100g 68 m 2 /g S* Four carbon black pellet compositions, G, H, I and J were produced in a continuous process by combining the carbon blacks in a batch pin pelletizer 15 together with a binder solution. The pellets were produced in a continuous pin pelletizer operating with rotor speed of 1000 rpm and dried in a heated rotating drum to provide dry pellets with a moisture content below The binder and carbon black utilized in each pelleting composition was as shown in the Table below.

Pellet Composition Carbon Black Binder G CB-3 water H CB-3 2% sorbitan monooleate with 20 moles ethylene oxide I CB4 water J CB-4 2% sorbitan monooleate with 20 moles ethylene oxide Carbon black pellet compositions G and I were control compositions, and carbon black pellet compositions H and J were carbon black compositions of the present invention.

The pellets were assessed for mass pellet strength using the procedures described above. The results were as follows: 19 Pellet Composition mass pellet strength kilograms G 6.35-7.26 (14-16 pounds) H 23.13 (51 pounds) I 4.53 (10 pounds) J 11.79 (26 pounds) The carbon black pellet compositions G, H, I and J were compounded into a polyether polyol, having a viscosity of 150 mPa.s at 250 C and a hydroxyl content of to produce a 30% carbon black content paste. In addition, a polyether polyol compositon was produced by compounding carbon black CB-4 10 into the polyol and adding 2% sorbitan monooleate with 20 moles ethylene oxide binder directly to the polyol. Each compounding operation involved prei dispersion under a high shear, Dispermat, mixer for 5 minutes at a speed of 2000 rpm.

The paste was then transferred to a triple roll mill for the final size 15 reduction process. The number of passes through the triple roll mill required to generate zero scratches on a Hegman gauge were noted together with the residual background "sand" value. The paste was then diluted with further polyol to produce a 15% carbon black loaded sample and the viscosity measured on a Carri-Med CS viscometer at a shear rate of 300 s-1. The results 20 were as shown in Table 3: Table 3 Number viscosity Carbon Black of passes sand" shear stress Pellet Composition triple roll (microns) (dyne/cm2) G 5 37 2800 H 5 19 1900 I 6 17 1860 J 5 17 1400 CB4, with Binder Added 7 26 1790 Directly to Polyol The above experiments illustrate the improved pellet strength and dispersion, and reduced compound viscosity, of the carbon black pellet compositions H and J of the present invention in comparison to use of carbon black compositions G and H pelletized with water only. The data also demonstrates the benefits of incorporating a binder directly onto the carbon black (pretreating the carbon black with a binder) in comparison to adding the binder to the polymer system.

This example is representative for polyurethane foam and sealant applications and demonstrates improvement in dispersion and rheology of the polymer compositions incorporating carbon black compositions of the present invention. The reduction in viscosity would allow use of low pressure to apply the polyurethane sealant in either automotive direct glazing or window 10 double/triple glazing unit operations.

Example 15-17 This example illustrates the advantages of using the carbon black S. el o compositions of the present invention in ink formulations.

Carbon black compositions G and H from Examples 11-14 were evaluated in a typical oil based gloss ink using the same process as outlined in examples 11-14. In this case the mill base and letdown system were an oil (McGee 47) and a heatset resin (Lawter Vehicle 3477) used in a ratio of 1:9 by weight. A third ink formulation was produced by adding sorbitan monooleate with 20 moles of ethylene oxide, to a composition of Carbon Black Composition 20 G and the oil utilized in the compounding process.

The compounding operation involved pre-dispersion under a high shear, Dispermat, mixer for 5 minutes at a speed of 2000 rpm. The paste was then transferred to a triple roll mill for the final size reduction process. The number of passes through the triple roll mill required to generate zero scratches on a Hegman gauge were noted together with the residual background "sand" value.

The paste was then diluted with further polyol to produce a 15% carbon black loaded sample and the viscosity measured on a Carri-Med CS viscometer at a shear rate of 300 s-1. The results were as shown in Table 4:

M

21 Table 4 Ink Formulation Number viscosity Carbon Black of passes "sand" shear stress Pellet Composition triple roll (microns) dyne/cm2) G 5 18 330 H 4 15 165 G, with binder added to oil 4 17 240 These results demonstrate the improved dispersion and reduced viscosity obtained when the binder composition utilized in the carbon black 10 compositions of the present invention is either incorporated onto the carbon black or with direct addition to the ink vehicle. Incorporating the binder onto the carbon black exhibits the most significant improvement. The binder would potentially help to reduce the mixing time for the ink and the reduced viscosity and improved dispersion would help to reduce wear in the application process.

15 Example 18-26 Examples 18-26 illustrate the use of carbon black compositions of the present invention in semiconductive compounds.

Three carbon black pellet compositions, K, L and M were produced by combining a fluffy carbon black, identified herein as CB-5, having a DBP of 140 20 cc/100g and a nitrogen surface area of 70 m 2 in a batch pin pelletizer together with a binder solution. The carbon black was combined with various binder solutions in a continuous pin pelletizer operating at 1050 rpm to provide wet pellets with levels of sorbitan monooleate with 20 moles ethylene oxide in amounts varying from 0 to The pellets were dried in a heated rotating drum to provide dry pellets with moisture content below The binder utilized in each pelleting composition was as shown in the Table below.

Pellet Composition Binder K water L 2% sorbitan monooleate 20 moles ethylene oxide M 4% sorbitan monooleate 20 moles ethylene oxide The carbon blacks were compounded into ethylene vinyl acetate resin vinyl acetate content, melt index using a twin screw extruder, to produce a 40% carbon black loaded compound The compound was subsequently extruded to form a tape and the level of carbon black dispersion assessed by measuring the number and size of surface imperfections using an optical microscope (magnification 100x) with a reflected light source, by the procedures described herein. The results are shown below: EVA Composition area of un-dispersed carbon black Carbon Black Composition S 10 K 0.0470% L 0.0056% M 0.0067% The reduction in undispersed carbon black would be seen in the final cable compound as an improvement in surface smoothness of the extruded ~15 cable. Reduction in surface imperfections of the semi-conductive insulation shield is known to reduce the frequency of electrical breakdown due to tree :growth.

~The EVA compositions containing carbon black compositions K and L disclosed above were evaluated for strippability onto a polyethylene substrate 20 using the following technique: The compounds containing 40% carbon black in the ethylene vinyl acetate resin were compounded in a Brabender mixer with 1% dicumyl peroxide while maintaining the mixing temperature below 1500 C.

The material was transferred to a heated hydraulic press (temperature 1300 C) and a plaque 1.2 mm thick produced. A 2 mm polyethylene plaque containing 1% dicumyl peroxide was produced in a similar manner. The two plaques were laminated together under a pressure of 7.030 kg/cm2 (100 psi) and exposed to a curing cycle of 1800 C for 15 minutes. The laminate was allow to cool to ambient temperature under pressure. The delamination force under a peeling angle of 180 degrees and a separation speed of 0.10 meters/minute (3.94 inches/minute) was recorded; the results are an average of 28 peel tests:

I

C

I c EVA Composition Carbon Black Composition kilogram/centimeter (Ib per 0.5 inch) K 2.33 0.16 (6.55 0.46) L 1.83 0.16 (5.12+1- 0.44) The data shows a reduction in strip force required to remove the semiconductive shield compound from the insulation layer. This is important in cable splicing operations or in making terminal connections. The lower strip force will result in a faster operation and minimise voids/imperfections from high strip force systems and hence reduce the potential for electrical breakdown in use.

Examples 27-37 Examples 27-37 illustrate the use of carbon black compositions in polyolefin masterbatch compositions.

Four carbon blacks were utilized to produce carbon black compositions of the present invention and control carbon black compositions. The carbon blacks utilized are designated herein as CB-6, CB-7, CB-8 and CB-9 and had the combination of analytical properties set forth below: Carbon Black DBP N 2

SA

cc/100 m 2 /g CB-6 140 68 20 CB-7 135 180 CB-8 136 120 CB-9 168 53 The carbon blacks were combined with either water or an aqueous solution of sorbitan monooleate with 20 moles of ethylene oxide in a continuous pelletizer operating with a rotor speed of 1000 rpm to produce wet pellets. The pellets were dried in an air circulating oven operating at 1200 C to produce dry pellets with moisture content below In all 11 different carbon black compositions were produced as shown below: Composition

N

O

P

Q

Carbon Black CB-6 Binder Water o re r e r o CB-6 CB-6 CB-6 CB-6 CB-7 CB-7 CB-8 CB-8 CB-9 CB-9 0.5% sorbitan monooleate with ethylene oxide 1.0% sorbitan monooleate with ethylene oxide 2.0% sorbitan monooleate with ethylene oxide 4.0% sorbitan monooleate ethylene oxide Water 2.0% sorbitan monooleate ethylene oxide Water 2.0% sorbitan monooleate ethylene oxide Water 2.0% sorbitan monooleate ethylene oxide with 20 moles 20 moles 20 moles 20 moles with 20 moles

V

with 20 moles with 20 moles The carbon black compositions were assessed for pellet strength and attrition resistance using the procedures described herein. The results are shown below in Table Table Composition pellet strength dust kilograms N 11.34 (25 Ibs.) 4.4 O 27.66 (61 Ibs.) 0.5 1.1 P 22.22 (49 Ibs.) 0.6 Q 24.94 (55 Ibs.) 0.2 0.4 R 22.67 (50 Ibs.) 0.8 0.6 S 19.95 (44 Ibs.) 3.6 15.0 T 37.64 (83 Ibs.) 0.3 U 28.11 (62 Ibs.) 0.8 5.2 V 53.97 (119 Ibs.) 0.2 0.4 W 7.7 (17 lbs.) 2.5 4.8 X 9.52 (21 Ibs.) 1.2 2.4 Each of the carbon black compositions was identically compounded into low density polyethylene having a melt index of 26 using a Brabender mixer to produce a masterbatch containing 40% carbon black. The viscosity of the masterbatch was measured at 1300 C and a shear rate of 50 s-l. The results are set forth in Table 6 below.

Table 6 Composition Viscosity (Pa.s) N 5116 0 4045 P 3389 Q 2873 R 2536 SS 4329 T 3695 S 15 U 4591 V 3804 W 5487 X 4373 The data in Table 6 illustrates the reduction in viscosity obtained by using 20 a carbon black treated with a binder composition of the present invention. This reduction in viscosity would facilitate ease of dispersion of the masterbatch into further polyethylene in a typical extrusion blown film or profile extrusion application; and also improve output efficiency. One would also expect an improvement in carbon black dispersion which would also provide an improvement in pigmentary efficiency, UV protection and mechanical performance tensile or impact strength).

Examples 38-49 This example illustrates the use of different binder compositions to produce carbon black compositions of the present invention, and the advantages of using the carbon black compositions of the present invention in ethyl vinyl acetate (EVA) applications.

Eleven carbon black compositions, HH, II, JJ, KK, LL, MM, NN, 00, PP, QQ and RR were produced by combining 400 g of a fluffy carbon black having a DBP of 128 cc/100g and a nitrogen surface area of 68 m 2 designated herein as CB-12, together with 8 g of binder dissolved in 500 g of water, in a batch pin pelletizer. The binder utilized in each composition was as follows: Composition Binder HH water II sucrose monoester of tallow fatty acid JJ sucrose monostearate 10 KK sucrose distearate LL ethoxylated glyceride S"o MM ethoxylated triglyceride NN SYNPERONIC PE/L61 surfactant 00 SYNPERONIC PE/85 surfactant 15 PP SYNPERONIC PE/F127E surfactant QQ SYNPERONIC PE/38E surfactant RR SYNPERONIC PE/108E surfactant SYNPERONIC is a trade name for surfactants produced and sold by ICI Chemical Polymers and comprise ethylene oxide propylene oxide 20 copolymers. SYNPERONIC PE grade surfactants as described in "Surfactants Europe", 2nd Ed. (edited by G.L. Hollis and published by Tergo Data, Darlington, UK, ISBN 0 9505473 1X) as polyethylene oxide-polypropylene oxide polyethylene oxide copolymers.

The mix was agitated at 800 rpm for 2 minutes to produce a pelletized carbon black. The carbon black pellets were dried at 1250 C until the moisture content was below 1%.

Mass pellet strength of the carbon black compositions was determined according to the procedures described herein. The results are set forth in Table 7 below.

Each of the carbon black compositions was combined with an ethylene vinyl acetate copolymer containing 40% vinyl acetate and a melt index of 3 in a Brabender mixer conditioned at 650 C. The compound was masticated for 6 0* 27 minutes at 50 rpm to produce a fully dispersed compound containing carbon black. These compounds were assessed for melt index (MI) at 1900 C using a 21.6 kg load, according to the procedures described herein. The results are also set forth in Table 7 below, which also shows the HLB of each binder.

Table 7 HLB MPS MI Disp. Of Comp Binder (kg) (g/10m) Dil.

Samples HH water 0.72 6.58 2C (1.6 lbs.) II sucrose monoester of tallow fatty acid 14.5 6.89 9.86 1C (15.2 Ibs.) jj sucrose monostearate 15.0 7.16 6.88 1B (15.8 Ibs.) KK sucrose distearate 12.0 10.34 9.18 1B (22.8 Ibs.) LL ethoxylate glyceride 15.7 2.22 8.84 1C (4.9 Ibs.) MM ethoxylated triglyceride 14.4 3.04 14.00 1D (6.7 Ibs.) NN SYNPERONIC PE/L61 surfactant 16.0 4.26 10.34 1B (9.4 Ibs.) 00 SYNPERONIC PE/85 surfactant 16.0 1.31 10.55 1C (2.9 Ibs.) pp SYNPERONIC PE/F127E surfactant 22.0 1.18 6.70 1E (2.6 Ibs.) QQ SYNPERONIC PE/38E surfactant 30.5 1.40 7.90 1B (3.1 Ibs.) RR SYNPERONIC PE/108E surfactant 27.0 1.59 7.97 1E Ibs.) Comp. Composition; Disp. Of Dil. Samples Dispersion of Diluted Samples.

These examples illustrate the improvement in dispersion quality and reduction in viscosity with improved pellet handling qualities, in a commercial system. These results would relate to shorter mixing cycles and improved extrusion characteristics.

Examples 50-52 These examples illustrates the production of carbon black compositions of the present invention, and the advantages of using the carbon black compositions of the present invention in ethyl vinyl acetate (EVA) applications.

Three carbon black compositions, SS, TT and UU were produced by combining a fluffy carbon black with a nitrogen surface area of 70 m2/g and a DBP of 140 cc/100g of carbon black, designated herein as CB-13, with a binder solution containing sorbitan monooleate in a continuous pin pelletiser operating i at 1050 rpm to provide wet pellets.

10 The resulting pellets containing either 2% or 4% binder were dried in a heated rotating drum to provide dry pellets with moisture contents below 0.6%.

The percentage of the binder utilized in each composition was as follows: Composition Binder by weight) SS 0.0 sorbitan monooleate (water) 15 TT 2% sorbitan monooleate UU 2% sorbitan monooleate The treated carbon blacks where compounded into various polymers using a Brabender mixer operating at 50 rpm and with an initial chamber temperature of 850 C. The mixing cycle time was 6 minutes. The compounds 20 were assessed for melt viscosity at 1300 C and a shear rate of 50s-1.

polymer Viscosity (Pa.s) percent binder 0 2 4 ethylene vinyl acetate (40% vinyl acetate, MI 3.0) 8155 3210 3080 ethylene vinyl acetate (18% vinyl acetate, MI 2.5) 7368 3564 3498 ethylene ethyl acrylate (18% ethyl acrylate, MI 6.0) 7018 3170 2558 4 A 29 The data illustrates a significant reduction in melt viscosity when using the designated binder, this would reflect in a reduction in die head pressure during the cable fabrication process. Visually this would be seen as an improvement is smoothness of the compound extrudate and also an increase in output rate.

The polymers utilized represent typical types of polymer used in wire and cable formulations used for conductor and semi-conductive shield applications.

The polymers containing either 18% vinyl acetate or ethyl acrylate are typically used in conductor or bonded semi-conductive shield applications while the 10 polymer containing 40% vinyl acetate is more suitable for a strippable semiconductive shield type product.

0:0. :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.

15 "Comprises/comprising" when used in this specification is taken to specify the presence of stated features, integers, steps or components, but does not a• ••preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. ••is components or groups thereof.

C

C 0

Claims (11)

1. A carbon black composition comprising: carbon black and 0.1% to 50%, by weight, of at least one binder which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

2. The carbon black composition of claim 1 wherein the binder has an HLB value from 8.0 to

3. The carbon black composition of claim 1 wherein the binder is present in OV 0.: S" an amount of 1.0 to 20 percent by weight

4. The carbon black composition of claim 1 wherein the carbon black is treated with the binder.

5. A polymer composition comprising: a polymer component and 0.1-65%, by weight, of a composition comprising a carbon black and 0.1% to 50%, by weight of at least one binder component which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer.

6. The polymer composition of claim 5 wherein the binder has an HLB value from 8.0 to

7. The polymer composition of claim 5 wherein the composition of carbon black and binder is present in an amount of 1.0 to 20 percent by weight.

8. The polymer composition of claim 5 wherein the carbon black is treated with the binder component. 31

9. An semi-conductive composition comprising:

25-55%, by weight, of a composition comprising a carbon black and to 10 parts per 100 parts of carbon black of at least one binder component which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer; 0 to by weight a stabilizer or antioxidant 0 to by weight an organic peroxide, preferably dicumyl peroxide; 0 to 10%, by weight a vinyl silane; the remainder being a polymer, or a blend of polymers, selected from the following group: ethylene homopolymer; ethylene copolymerized with one or more alpha olefins; ethylene copolymerized with propylene and a diene monomer; and ethylene copolymer with one or more monomers selected from vinyl acetate, acrylic acid, methacrylic acid, esters of acrylic or methacrylic acid containing 1 to 8 carbon atoms, maleic anhydride or a monoester derived from fumaric or maleic acid, vinyl chloride or vinylidene chloride. 10. The semiconductive composition of claim 9 wherein the carbon black is treated with the binder. 11. A masterbatch composition comprising:

70-40%, by weight of an ethylene homopolymer or copolymer, where the comonomer is selected from hexene, propene, butene, octene or vinyl acetate; and 30-60%, by weight, of a composition comprising a carbon black and 0.1- by weight, of at least one binder component which is a polyethylene oxide polypropylene oxide polyethylene oxide block copolymer. 12. The masterbatch composition of claim 11 wherein the carbon black is treated with the binder. 32 13. An article of manufacture formed from the composition of claim 14. The carbon black composition of claim 1 further comprising 0.1% to by weight, sucrose distearate. DATED this 25th day of May, 1999. CABOT CORPORATION WATERMARK PATENT TRADEMARK ATTORNEYS 290 BURWOOD ROAD HAWTHORN VICTORIA 3122 AUSTRALIA KJS:RBP:JL VAX doc 027 AU003131.WPC o*