Wear resistant rubber composition for use on mining equipment

Abstract

This disclosure relates to a wear resistant rubber composition for lining mining equipment. The composition comprises a tri-elastomer blend of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer. The composition further includes silicon dioxide, hydrocarbon resin, cologhony, silane and an antioxidant.

Description

[0001] WEAR RESISTANT RUBBER COMPOSITION FOR USE ON MINING EQUIPMENT TECHNICAL FIELD

[0002]

[0001] This disclosure relates to a rubber composition with high wear resistance and high chemical resistance and to a method of manufacturing the composition. In particular, but not exclusively, the disclosure relates to a rubber composition for use in the oil sands and chemical industries and to a method of manufacturing the composition.

[0003] BACKGROUND TO THE DISCLOSURE

[0004]

[0002] Rubber compositions are commonly applied to equipment in the mining sector and in mineral processing plants in order to reduce the rate of wear on the equipment. The equipment includes spools, pumps and hoses. For example, in Canada in the Athabasca area and in Venezuela at the banks of the Orinoco river at the state of Bolivar, are petroleum resources which are located deep underground. It is a difficult task to extract oil sands from these petroleum resources. The process of extraction involves transporting oil sands to a remote area using pipes and conveyor belts that are suitable for transporting tacky substances such as oil sands and clays.

[0005]

[0003] The oil sands are too thick and the angular shape of the grains of the sands make them abrasive and difficult to handle using rubber compositions that do not have high wear resistance and high chemical resistance.

[0006]

[0004] Traditionally, a lead cured neoprene rubber is used as a liner on the equipment. Lead oxide, which has a heavy metal footprint, is used in the manufacturing of the lead cured neoprene rubber. Current substitutions for lead-cured neoprene in hot-water / hydrocarbon blended applications involve replacing the neoprene with nitrile, which does not have near the wear resistance needed. Magnesium oxide and zinc oxide are also alternative cure systems for neoprene, but fall short when exposed to high temperature water in terms of property maintenance and swell resistance.

[0007] SUMMARY OF THE DISCLOSURE

[0008]

[0005] In accordance with a first aspect of the disclosure there is provided a wear resistant rubber composition for lining mining equipment, the rubber composition comprising: (a) a trielastomer blend of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer; (b) silicon dioxide; (c) hydrocarbon resin; (d) cologhony; (e) silane; and (f) an antioxidant.

[0009]

[0006] Preferably, the antioxidant comprises a diaryl-, dialkil-aryl, or dialkyl -P phenylamine, and even more preferably, the antioxidant comprises diphenylamine.

[0010]

[0007] The composition may further include any one or a combination of the following: stearic acid, a processing additive, and an additional antioxidant.

[0008] Preferably, the additional antioxidant comprises 4, 4’-Bis (alpha, alpha-dimethylbenzyl) diphenylamine.

[0011]

[0009] In one embodiment, the wear resistant rubber composition further includes an additional mixture consisting of any one of or combination of the following: sulfur, N-cyclohexyl- 2-benzothiazole sulfenamide (CBS), an accelerator, a curing agent, Zinc Oxide, anti-scorching agent, a filler, trimethylolpropane trimethacrylate and colophony.

[0012]

[0010] Preferably, the accelerator comprises benzothiazyl disulfide.

[0013]

[0011] Preferably, the curing agent comprises Zisnet F-ET or Triazine compound.

[0014]

[0012] Preferably, the anti-scorching agent comprises N-(Cyclohexylthio)phthalimide (PVI).

[0015]

[0013] Preferably, the filler comprises carbon black.

[0016]

[0014] Preferably, the composition has a specific gravity of about 1.20 to about 1.30, and a Shore hardness of about 60 Shore A to about 70 Shore A.

[0017]

[0015] Preferably, the composition has a tensile strength of about 2200 to about 2600 psi (15168 to 17926 KPa).

[0018]

[0016] Preferably, the tri-elastomer blend comprises: about 15 to 19 wt% of epichlorohydrin elastomer, about 15 to 19 wt% of epoxidised natural elastomer and about 15 to 19 wt% of nitrile elastomer in relation to the total weight of the composition.

[0019]

[0017] The composition may comprise about 20 to 30 wt% of silicon dioxide, about 4 to 7 wt% of hydrocarbon resin, about 4 to 7 wt% of cologhony, about 1 to 4 wt% silane, about 1 to 2 wt% of the antioxidant, about 0 to 1 w% of stearic acid, about 0 to 1 wt% of the processing additive, about 0 to 2 wt% of the additional antioxidant in relation to the total weight of the composition.

[0018] Preferably, the combination of any one of stearic acid, processing additive and the additional antioxidant are in an amount of 5 wt% or less in relation to the total weight of the composition.

[0020]

[0019] In one example, the additional mixture consists of: about 0 to 2 wt% sulfur; about 0 to 2 wt% N-cyclohexyl-2-benzothiazole sulfenamide (CBS); about 0 to 2 wt% accelerator; about 0 to 2 wt% curing agent; about 0 to 2 wt% Zinc Oxide; about 0 to 2 wt% anti-scorching agent; about 0 to 2 wt% filler; about 0 to 2 wt% trimethylolpropane trimethacrylate; and / or about 0 to 2 wt% colophony in relation to the total weight of the composition.

[0020] Preferably, the combination of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), accelerator, curing agent, Zinc Oxide, anti-scorching agent, filler, trimethylolpropane tri methacrylate and / or colophony are in an amount of 18 wt% or less.

[0021]

[0021] In accordance with another embodiment of the disclosure, there is provided a method of manufacturing a wear resistant rubber composition including the steps of: (a) providing a trielastomer mixture of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer; (b) blending the mixture of step (a) in a blending equipment for about 2 minutes to produce a tri-elastomer blend; (c) mixing any one of or combination of silicon dioxide, hydrocarbon resin, cologhony, silane, an antioxidant, stearic acid, a processing additive, and an additional antioxidant in a separate container to produce a second mixture; (d) loading the second mixture of step (c) into the blending equipment of step (b) and blending the second mixture with the tri-elastomer blend for about 90 seconds; (e) mixing any one of or combination of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), an accelerator, a curing agent, Zinc Oxide, anti-scorching agent, a filler, trimethylolpropane trimethacrylate and colophony in a second container to produce a third mixture; and (f) loading the third mixture of step (e) into the blending equipment of step (b) and (d) and mixing to 250°F (121°C) to produce the wear resistant rubber composition.

[0022] BRIEF DESCRIPTION OF THE DRAWINGS

[0023]

[0022] Notwithstanding any other forms which may fall within the scope of the rubber composition and method as set forth in the Summary, specific embodiments will now be described, by way of example, and with reference to the accompanying drawings in which:

[0023] Figure 1 shows a % inch and 1 inch (6.35 and 12.7 mm) plate sample prepared for upside down autoclave cure in accordance with an embodiment of the disclosure;

[0024]

[0024] Figure 2 shows a large plate of Figure 1 after autoclave cure; and

[0025]

[0025] Figure 3 shows a calendar including a produced batch of a rubber composition in accordance with an embodiment of the disclosure.

[0026] DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

[0027]

[0026] Before any embodiments of the disclosure are explained in detail, it is to be understood that the disclosure is not limited in its application to the details of construction and the arrangement of components set forth in the following description.

[0028]

[0027] As used herein, throughout this specification, the singular forms “a”, “an” and “the” include the plural form, unless the context clearly indicates otherwise.

[0029]

[0028] The terminology and phraseology used herein is for the purpose of description and should not be regarded as limiting. The use of the terms “comprising”, “containing”, “having”, “including”, and variations thereof used herein, are meant to encompass the items listed thereafter, and equivalents thereof as well as additional items.

[0030]

[0029] In this specification, all amounts are expressed as percentage weight in relation to the total weight (% w / w) of the composition. In the context of this specification, the term "about," is understood to refer to a range of numbers that a person of skill in the art would consider equivalent to the recited value in the context of achieving the same function or result.

[0031]

[0030] The present disclosure relates, in some embodiments, to a wear resistant rubber composition for use in the oil sands and chemistry industries. Oil sands are composed of a fine structure of siliceous sand grain coated with a thin water film which is further surrounded with bitumen. The presence of bitumen, which is a hydrocarbon, makes the oil sands a valuable energy source which is worth processing. Once the bitumen is extracted from the sands, the bitumen can be upgraded into crude oil and then refined into common petroleum products such as gasoline, kerosene or gasoil. In accordance with one aspect of the disclosure, there is provided a wear resistant rubber composition for lining mining equipment, in particular, oil sands mining equipment. The mining equipment includes a conveyor belt, spools, pumps and hoses.

[0032]

[0031] The wear resistant rubber composition comprises a tri-elastomer blend of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer. As used herein, for example, the tri-elastomer blend comprises of about 15 to 19 wt% of epichlorohydrin elastomer, 15 to 19 wt% of epoxidised natural elastomer and 15 to 19 wt% of nitrile elastomer. In another form, the blend comprises of about 17 to 19 wt% of epichlorohydrin elastomer, 17 to 19 wt% of epoxidised natural elastomer, and 17 to 19 wt% of nitrile elastomer. In a further form, the blend comprises of about 18 wt% of epichlorohydrin elastomer, about 18 wt% of epoxidised natural elastomer and about 18 wt% of nitrile elastomer in relation to the total weight of the composition.

[0033]

[0032] In addition to the tri-elastomer blend, the wear resistant rubber composition further includes any one or combination of the following constituents: silicon dioxide, hydrocarbon resin such as Novares C10 (RTM) or indene coumarone resin, cologhony or pine resin, silane, and an antioxidant. The antioxidant comprises diaryl-, dialkil-aryl, or dialkyl -P phenylamine. Preferably, the antioxidant is a diphenylamine antioxidant.

[0034]

[0033] According to one example, the wear resistant rubber composition comprises: silicon dioxide in an amount of about 20 to 30 wt%, preferably about 24 to 26 wt%; hydrocarbon resin or indene coumarone in an amount of about 4 to 7 wt%; cologhony or pine resin in an amount of about 4 to 7 wt%, preferably about 6 wt%; silane in an amount of about 1 to 4 wt%, preferably about 3 to 4 wt%; and an antioxidant in an amount of about 1 to 2 wt% in relation to the total weight of the composition.

[0034] According to another example, the wear resistant rubber composition further comprises any one or a combination of the following constituents: stearic acid, a processing additive such as Struktol WB 222 (RTM), and an additional antioxidant. The additional antioxidant is 4, 4’- Bis (alpha, alpha-dimethylbenzyl) diphenylamine.

[0035]

[0035] The wear resistant rubber composition may comprise stearic acid in an amount of 0 to 1 wt%, processing additive in an amount of 0 to 1 wt%, and the additional antioxidant in an amount of 0 to 2 wt%. Preferably, the combination of stearic acid, processing additive and the additional antioxidant are in an amount of about 5 wt% or less, preferably about 4 wt% or less.

[0036] In yet another example, the wear resistant rubber composition may further include an additional mixture consisting of any one or combination of the following constituents: sulfur, N- cyclohexyl-2-benzothiazole sulfenamide (CBS), an accelerator such as benzothiazyl disulfide, a curing agent for example Zisnet F-ET (RTM) or Triazine compound, Zinc Oxide, antiscorching agent such as N-cyclohexyl(thio)phtalimide (PVI), a filler such as carbon black, trimethylolpropane trimethacrylate and colophony.

[0036]

[0037] In this example, the wear resistant rubber composition comprises sulfur in an amount of about 0 to 2 wt%, N-cyclohexyl-2-benzothiazole sulfenamide (CBS) in an amount of about 0 to 2 wt%, accelerator in an amount of about 0 to 2 wt%, curing agent in an amount of about 0 to 2 wt%, Zinc Oxide in an amount of about 0 to 2 wt%, anti-scorching agent in an amount of about 0 to 2 wt%, filler in an amount of about 0 to 2 wt%, trimethylolpropane trimethacrylate in an amount of about 0 to 2 wt%, and colophony in an amount of about 0 to 2 wt%.

[0037]

[0038] According to some examples, the combination of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), accelerator, curing agent, Zinc Oxide, anti-scorching agent, filler, trimethylolpropane trimethacrylate and / or colophony in the additional mixture is in an amount of 18 wt% or less. In another form, the combination of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), accelerator, curing agent, Zinc Oxide, anti-scorching agent, filler, trimethylolpropane trimethacrylate and / or colophony in the additional mixture is in an amount of about 10 wt% or less. In yet another form, the combination of sulfur, N-cyclohexyl-2- benzothiazole sulfenamide (CBS), accelerator, curing agent, Zinc Oxide, anti-scorching agent, filler, trimethylolpropane trimethacrylate and / or colophony in the additional mixture is in an amount of about 8 wt% or less.

[0038]

[0039] Surprisingly, the inventors have been able to manufacture a lead-free wear resistant rubber composition for use in lining mining equipment in the oil sands industries which has good wear, hydrocarbon and hot water resistance. The wear resistant rubber composition in accordance with the disclosure does not contain lead (0 wt% lead) and is capable of resisting the oxidation process encountered in lining mining equipment using a rubber composition which does not include lead.

[0040] In some examples, the wear resistant rubber composition, after curing, has a Shore hardness of about 60 to 70 Shore A, at least about 60 Shore A, or at least about 62 Shore A, or at least about 64 Shore A, or at least about 66 Shore A, preferably, the shore hardness is about 62 Shore A to about 64 Shore A. The Shore A hardness values were measured according to the method detailed in ASTM D2240 using a handheld durometer tester at ambient temperature (e.g. 23°C).

[0039]

[0041] In some examples, the wear resistant rubber composition has a specific gravity (SG) of about 1.20 to about 1.30, preferably about 1.22 to 1.25. The specific gravity was tested according to the method detailed in ASTM 297 using the hydrostatic method. The mass of the specimen was measured both in air and in water at ambient temperature (23°C). The calculation of specific gravity according to ASTM D297 involves the following steps:

[0040] 1. Weighing the specimen in air: recording this weight as (a).

[0041] 2. Weighing the specimen in water: recording this weight as (b).

[0042] 3. Weighing the sinker (if used) in water: recording this weight as (w).

[0043] The formula for sprecific g aravity J is: SG = — (( —a+w) —-Z> -)

[0044]

[0042] In some examples, the wear resistant rubber composition has a tensile strength of about 2200 to 2600 psi (15168 to 17926 KPa). The tensile strength was measured according to ASTM D412 Method C. This method involves preparing a rubber plate by curing in a mold to about 0.08 inches thick (0.002 m). Tensile dumbbell die C specimens according D412 are punched from the plate and pulled at a constant strain between two grips to determine the ultimate tensile strength at break. The tests are conducted at ambient temperature (about 23°C).

[0045]

[0043] The wear resistant rubber composition for lining mining equipment in accordance with the disclosure is manufactured using the following steps: (a) providing a tri-elastomer mixture of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer; (b) blending the mixture of step (a) in a blending equipment for about 2 minutes to produce a tri-elastomer blend; (c) mixing any one of or combination of silicon dioxide, hydrocarbon resin, cologhony, silane, an antioxidant, stearic acid, a processing additive, and an additional antioxidant as necessary in a separate container to produce a second mixture; (d) loading the second mixture of step (c) into the blending equipment of step (b) and blending the second mixture with the tri- elastomer blend for about 90 seconds; (e) mixing any one of or combination of sulfur, N- cyclohexyl-2-benzothiazole sulfenamide (CBS), an accelerator, a curing agent, Zinc Oxide, anti-scorching agent, a filler, trimethylolpropane trimethacrylate and colophony in a second container to produce a third mixture; and (f) loading the third mixture of step (e) into the blending equipment of step (b) and (d) and mixing to 250°F (121 °C) to produce the wear resistant rubber composition.

[0044] The present disclosure will now be further described more fully with reference to the below non-limiting examples.

[0046] Example 1 : lab batch rubber composition in accordance with the disclosure

[0047]

[0045] A lab batch of a rubber composition in accordance with the disclosure was mixed, calendared and tested according to the functional specification requirements. The rubber composition remained soft and pliable for at least one month after being mixed and calendared. This was unexpected as some traditional rubber compositions crystalize after a few days, and are quite hard before being warmed up again.

[0048]

[0046] The results obtained from the test work is provided in Table 1 below. Wet abrasion resistance of the rubber composition was measured according to ASTM D5963, and the Abrasion Resistance Index (ARI) was calculated and gave a result of 147%. The testing was carried out on a Zwick Abrasion Tester in accordance with ASTM Standard D5963: Standard Test Method for Rubber Property-Abrasion Resistance (Rotary Drum Abrader).

[0049]

[0047] Cylindrical specimens of a diameter of 16 mm were drilled out of a cured sheet of rubber with a minimum thickness of 6 mm. These samples were secured into the specimen holder of the Zwick Abrasion Tester, and ran along a rotating drum with abrasive paper on its surface. The mass of the specimens were taken before and after the test and the mass and volume losses were calculated using the specific gravity. The Abrasion Resistance Index (ARI) was determined by the ratio of the volume loss of a standard rubber to that of the test rubber expressed as a percentage. The standard rubber would yield a percentage value of 100, and any value above 100% for the test rubber would mean improved wear while any value below 100 would mean decreased wear.

[0050]

[0048] The calculation for ARI is , _ 100

[0051]

[0049] The change in bitumen and change in water results as shown in Table 1 were determined from immersing the rubber compositions in Bitumen for one set, and in water for the other set. These tests took place at 85°C for 7 days. The tests were carried out according to ASTM D471 - Standard Test Method for Rubber Property- Effects of Liquids.

[0052]

[0050] An attempt was made to dissolve the rubber composition in xylene in order to create a tack cement. The polarity and chemical resistance of the rubber composition is too strong for the rubber composition to be dissolved in xylene. The rubber composition swelled up significantly but did not break down into a viscous liquid.

[0053]

[0054] Table 1 : Properties of the rubber composition in accordance with one aspect of the disclosure

[0055] Example 2: rubber composition tack and adhesion testing

[0056]

[0051] When the rubber composition was rolled out on a hot table it appeared smooth and tacky.

[0057]

[0052] Negligible shrinkage was observed after half an hour.

[0058]

[0053] The material was tacky to the touch and stuck modestly when pressed upon itself.

[0059]

[0054] Several small steel coupons were grit blasted, primed with Chemlok 205 (RTM) and coated with Chemlok 6220 (RTM) adhesive.

[0060]

[0055] The rubber-to-metal specimens were then prepared by cutting to the approximate width and length of the metal coupon and stitching them to the surface.

[0061]

[0056] One large test plate was also prepared, utilizing the same bonding system as the coupons. It was cured upside down in the autoclave to validate the strength of the tack throughout the curing process.

[0057] An initial layer of 14” (6.35 mm) of the rubber composition was applied and then a 1 ” (3.18 mm) layer half the size was applied on top of the first layer as shown in Figure 1. All the samples were then autoclave cured for 3 hours and 20 minutes at 275° F (135°C) and at a maximum pressure of 65 psi (448 KPa).

[0062]

[0058] After curing, the specimens were tested by hand and appeared to maintain a good bond as shown in Figure 2. The rubber-to-metal coupons were pull tested after 16 hours for adhesion strength, and the upside down plate stayed in place and cured smoothly.

[0063] Example 3: calendaring of the rubber composition

[0064]

[0059] The produced batch of a rubber composition in accordance with the disclosure was milled, rolled off and fed to a calendar as shown in Figure 3.

[0065]

[0060] The upper and lower roll temperatures for the calendar were set at 176°F (80°C) and the rubber moved through the main roll at about 180°F (82°C).

[0066]

[0061] The batch flowed easily over the rolls and onto the ply-table.

[0067]

[0062] The material stuck immediately and could not be pulled apart by hand. 1 / 4” (6.35 mm) was the final roll thickness based on available material.

[0068]

[0063] It will be appreciated that the above are only some examples of the disclosure and that there may be other variations without departing from the scope of the disclosure. It is easily understood from the present application that the particular features of the present disclosure, as generally described and illustrated in the figures, can be arranged and designed according to a variety of different configurations. In this way, the description of the present disclosure and the related figures are not provided to limit the scope of the disclosure but simply represent selected examples.

[0069]

[0064] The skilled person will understand that the technical characteristics of a given example can in fact be combined with characteristics of another example, unless otherwise expressed or it is evident that these characteristics are incompatible. Also, the technical characteristics described in a given example can be isolated from the other characteristics of this example unless otherwise expressed.

Claims

CLAIMS1. A wear resistant rubber composition for lining mining equipment, the rubber composition comprising:(a) a tri-elastomer blend of epichlorohydrin elastomer, epoxidised natural elastomer and nitrile elastomer;(b) silicon dioxide;(c) hydrocarbon resin;(d) cologhony;(e) silane; and(f) an antioxidant.

2. The wear resistant rubber composition of claim 1, wherein the antioxidant comprises diaryl-, dialkil-aryl, or dialkyl -P phenylamine.

3. The wear resistant rubber composition of claim 1 or 2, wherein the antioxidant comprises diphenylamine.

4. The wear resistant rubber composition of any one of the preceding claims, wherein the composition further includes any one of stearic acid, a processing additive, an additional antioxidant or a combination thereof.

5. The wear resistant rubber composition of claim 4, wherein the additional antioxidant comprises 4, 4’- Bis (alpha, alpha-dimethylbenzyl) diphenylamine.

6. The wear resistant rubber composition of any one of the preceding claims, wherein the composition further includes an additional mixture consisting of any one of sulfur, N- cyclohexyl-2- benzothiazole sulfenamide (CBS), an accelerator, a curing agent, Zinc Oxide, anti-scorching agent, a filler, trimethylolpropane trimethacrylate and colophony or combination thereof.

7. The wear resistant rubber composition of claim 6, wherein the accelerator comprises benzothiazyl disulfide, the curing agent comprises Zisnet F-ET or Triazine compound, the anti-scorching agent comprises N-(Cyclohexylthio)phthalimide (PVI) and the filler comprises carbon black.

8. The wear resistant rubber composition of any of the preceding claims, wherein the composition has a specific gravity of about 1.20 to about 1.30, and a shore hardness of about 60 Shore A to about 70 Shore A.

9. The wear resistant rubber composition of any one of the preceding claims, wherein the composition has a tensile strength of about 2200 to about 2600 psi (15168 to 17926 KPa).

10. The wear resistant rubber composition of any one of the preceding claims, wherein the tri-elastomer blend comprises of about 15 to 19 wt% of epichlorohydrin elastomer, 15 to 19 wt% of epoxidised natural elastomer, and 15 to 19 wt% of nitrile elastomer in relation to the total weight of the composition.11 . The wear resistant rubber composition of any of the preceding claims comprising about 20 to 30 wt% of silicon dioxide in relation to the total weight of the composition.

12. The wear resistant rubber composition of any one of the preceding claims comprising about 4 to 7 wt% of hydrocarbon resin in relation to the total weight of the composition.

13. The wear resistant rubber composition of any one of the preceding claims comprising about 4 to 7 wt% of cologhony in relation to the total weight of the composition.

14. The wear resistant rubber composition of any one of the preceding claims comprising about 1 to 4 wt% silane in relation to the total weight of the composition.

15. The wear resistant rubber composition of any one of the preceding claims comprising about 1 to 2 wt% of the antioxidant in relation to the total weight of the composition.

16. The wear resistant rubber composition of any one of claims 4 to 15 comprising about 0 to 1 w% of stearic acid in relation to the total weight of the composition.

17. The wear resistant rubber composition of any one of claims 4 to 16 comprising about 0 to 1 wt% of the processing additive in relation to the total weight of the composition.

18. The wear resistant rubber composition of any one of claims 4 to 17 comprising about 0 to 2 wt% of the additional antioxidant in relation to the total weight of the composition.

19. The wear resistant rubber composition of any one of claims 4 to 18, wherein the combination of any one of stearic acid, processing additive and the additional antioxidant are in an amount of about 5 wt% or less in relation to the total weight of the composition.

20. The wear resistant rubber composition of any one of claims 6 to 19 comprising about 0 to 2 wt% sulfur, 0 to 2 wt% N-cyclohexyl-2-benzothiazole sulfenamide (CBS), 0 to 2 wt% accelerator, 0 to 2 wt% curing agent, 0 to 2 wt% Zinc Oxide, 0 to 2 wt% antiscorching agent, 0 to 2 wt% filler, 0 to 2 wt% trimethylolpropane trimethacrylate and / or 0 to 2 wt% colophony in relation to the total weight of the composition.21 . The wear resistant rubber composition of claim 20, wherein the combination of sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), accelerator, curing agent, Zinc Oxide, anti-scorching agent, filler, trimethylolpropane trimethacrylate and / or colophony are in an amount of 18 wt% or less in relation to the total weight of the composition.

22. A method of manufacturing a wear resistant rubber composition including the steps of:(a) providing a tri-elastomer mixture of epichlorohydrin elastomer, epoxidized natural elastomer and nitrile elastomer;(b) blending the mixture of step (a) in a blending equipment for about 2 minutes to produce a tri-elastomer blend;(c) mixing silicon dioxide, hydrocarbon resin, cologhony, silane, an antioxidant, stearic acid, a processing additive, and an additional antioxidant in a separate container to produce a second mixture;(d) loading the second mixture of step (c) into the blending equipment of step (b) and blending the second mixture with the tri-elastomer blend for about 90 seconds;(e) mixing sulfur, N-cyclohexyl-2-benzothiazole sulfenamide (CBS), an accelerator, a curing agent, Zinc Oxide, anti-scorching agent, a filler, trimethylolpropane tri methacrylate and colophony in a second container to produce a third mixture; and(f) loading the third mixture of step (d) into the blending equipment of step (b) and (d) and mix to 250°F (121 °C) to produce the wear resistant rubber composition.

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