Process oil for rubber compounding
12018155 ยท 2024-06-25
Assignee
Inventors
Cpc classification
C11B1/025
CHEMISTRY; METALLURGY
International classification
B60C1/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
Process oils comprising distiller's corn oil are incorporated into rubber compositions useful for manufacturing tires or various tire components including tire sub-treads.
Claims
1. A rubber composition comprising: an elastomer; and a process oil comprising distiller's corn oil having a free fatty acid content greater than 20% w/w of the total distiller's corn oil and a fatty acid alkyl ester content less than 16% w/w of the total distiller's corn oil.
2. The rubber composition of claim 1, comprising about 2 to about 70 parts distiller's corn oil per hundred rubber (PHR).
3. The rubber composition of claim 1 wherein the elastomer is styrene-butadiene rubber (SBR), ethylene propylene diene monomer (EPDM), natural rubber (NR), nitrile rubber (NBR), a component of natural rubber, polybutadiene or mixtures thereof.
4. The rubber composition of claim 1, wherein the distiller's corn oil is post distillation distiller's corn oil.
5. The rubber composition of claim 1, wherein the distiller's corn oil is processed during fermentation to decrease fatty acid alkyl ester content.
6. The rubber composition of claim 1, wherein the distiller's corn oil is exposed to heat in the presence of water.
7. The rubber composition of claim 1, wherein the distiller's corn oil is exposed to one or more enzymes in the presence of water.
8. The rubber composition of claim 1 wherein the distiller's corn oil is exposed to acid in the presence of water to increase free fatty acid content.
9. The rubber composition of claim 1, wherein the distiller's corn oil is the separation product of a post-fermentation emulsion exposed to a pH of less than 8 to increase the free fatty acid content in the distiller's corn oil.
10. The rubber composition of claim 1, wherein the distiller's corn oil is exposed to a caustic to saponify the distiller's corn oil, then exposed to an acid to generate free fatty acid.
11. The rubber composition of claim 1, further comprising one or more of: one or more fillers; one or more activators; one or more antioxidants; one or more curatives; and one or more accelerators.
12. The rubber composition of claim 1, comprising: between 20 PHR and 100 PHR filler; between 1 PHR and 10 PHR activator; between 0.1 PHR and 5 PHR antioxidant; between 0.1 and 2.0 PHR curative; and between 0.1 and 3.0 PHR accelerator.
13. The rubber composition of claim 1, wherein the distiller's corn oil is post fermentation distiller's corn oil.
14. The rubber composition of claim 13, wherein the distiller's corn oil is post fermentation distiller's corn oil processed to decrease fatty acid alkyl ester content.
15. The rubber composition of claim 1, wherein the distiller's corn oil includes added free fatty acid.
16. The rubber composition of claim 15, wherein the free fatty acid is stearic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, and mixtures thereof.
17. The rubber composition of claim 1, wherein the distiller's corn oil has been processed to reduce fatty acid alkyl ester.
18. The rubber composition of claim 17, wherein the distiller's corn oil is a first fraction obtained by a separation operation to produce the first fraction having relatively low fatty acid alkyl ester and a second fraction having relatively high fatty acid alkyl ester.
19. The rubber composition of claim 18, wherein the first fraction includes free fatty acid added after the first fraction separated from the distiller's corn oil.
20. The rubber composition of claim 18, wherein the first fraction has been treated with an enzyme to increase free fatty acid content after the first fraction has been separated from the distiller's corn oil.
21. The rubber composition of claim 18, wherein the separation operation includes a distillation operation.
22. The rubber composition of claim 18, wherein the separation operation includes a short path evaporator.
23. The rubber composition of claim 18, wherein the separation operation includes (i) adjusting the temperature of the distiller's corn oil and (ii) filtering or centrifuging the distiller's corn oil.
24. The rubber composition of claim 18, wherein the separation operation includes neutralizing the distiller's corn oil and filtering or centrifuging it.
Description
BRIEF DESCRIPTION OF THE FIGURES
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
DESCRIPTION
(11) It is to be understood that this invention is not limited to particular compositions, methods, and experimental conditions described, as such methods and conditions may vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the appended claims.
(12) As used in this specification and the appended claims, the singular forms a, an, and the include plural references unless the context clearly dictates otherwise. Thus, for example, a reference to a method includes one or more methods, and/or steps of the type described herein and/or which will become apparent to those persons skilled in the art upon reading this disclosure and so forth.
(13) The word exemplary is used to mean serving as an example, instance, or illustration. Any embodiment or design described as exemplary is not necessarily to be construed as preferred or advantageous over other embodiments or designs, nor is it meant to preclude equivalent exemplary structures and techniques known to those of ordinary skill in the art. Rather, use of the word exemplary is intended to present concepts in a concrete fashion, and the disclosed subject matter is not limited by such examples.
(14) The term or is intended to mean an inclusive or rather than an exclusive or. To the extent that the terms comprises, has, contains, and other similar words are used in either the detailed description or the claims, for the avoidance of doubt, such terms are intended to be inclusive in a manner similar to the term comprising as an open transition word without precluding any additional or other elements.
(15) Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All patents, applications and non-patent publications mentioned in this specification are incorporated herein by reference in their entireties.
(16) It has been determined by the inventors that introduction of vegetable oils, including distiller's corn oil (DCO), improves the performance of the rubber compounds in a number of evaluations including: tensile strength, elongation, modulus, heat aging, tear properties, DIN abrasion, and DeMattia flex resistance. DCO compositions with high free fatty acid (FFA) and low fatty acid alkyl ester (FAAE) give the surprising performance results when used as process oils in rubber compositions. Incorporation of DCO in the rubber formulation can improve the vulcanization process by altering the curing time and lowering the energy consumption during manufacture due to viscosity improvements as shown herein. In addition, less DCO can be used than a petroleum-derived process oil to achieve the same or better rubber properties.
(17) In a conventional ethanol plant, corn is used as a feedstock and ethanol is produced by fermentation of the starch contained within the corn. The fermentation product includes ethanol, water, and soluble components as well as residual unfermented particulate matter (among other things). The fermentation product is distilled and dehydrated to recover ethanol. The residual matter (e.g., whole stillage) comprising water, soluble components, oil, and unfermented solids can be further processed to separate out desirable fermentation by-products, for example, corn oil.
(18) Corn oil from the fermentation product can be recovered from fermentation residue according to conventional processes, e.g., extracted post-fermentation as a co-product of dry grind ethanol production or conventional ethanol production. Corn oil extraction may be carried out by single or double pass centrifugation steps, and with or without the use of demulsifiers or caustic to improve oil isolation from the remaining aqueous phase. Corn oil can also be provided from fermentation residue by adjusting the pH of the corn fermentation residue to provide a corn oil layer and an aqueous layer; and separating the corn oil layer from the aqueous layer. Corn oil with increased FFAs can also be obtained by exposing the corn oil to heat in the presence of water, exposing the corn oil to one or more enzymes in the presence of water, exposing the corn oil to acid in the presence of water, exposing the corn oil to a pH of less than about 8, or exposing the corn oil to a caustic to saponify the corn oil and then an acid. Finally, the FFA content of a corn oil can be increased by simply adding FFAs to the corn oil. The FFA can be stearic acid, palmitic acid, oleic acid, linoleic acid, linolenic acid, and mixtures thereof. The distiller's corn oil can contain at least 4% w/w FFAs, for example, at least 10%, at least 12%, at least 15%, at least 20%, at least 30%, at least 40%, or at least 50% FFAs.
(19) The corn oil can be processed to reduce fatty acid alkyl ester (FAAE) content or increase FFA of first fraction by the strategies mentioned above. In some aspects, the corn oil is a first fraction of corn oil separated from a corn oil by a separation operation, for example, a distillation operation or a short path evaporator, to produce the first fraction having relatively low FAAE and a second fraction having relatively high FAAE. The first fraction can include FFA added after the first fraction is separated from the corn oil. In some aspects, the first fraction has been treated with an enzyme to increase FFA content after the first fraction has been separated from the corn oil. The separation operation can include (i) adjusting the temperature of the corn oil and (ii) filtering or centrifuging the corn oil. The separation operation can also include neutralizing the corn oil and filtering or centrifuging it. The first fraction FFA content can also be increased by the aforementioned strategies.
(20) Table 1 provides characteristics of an exemplary DCO useful herein. Table 2 provides a compositional analysis of an exemplary DCO useful herein. Along with the analytes, the methods and conditions by which the values were measured are also provided.
(21) TABLE-US-00001 TABLE 1 Exemplary DCO Specifications Free Fatty Acids (FFAs), mass % ?15.0 Moisture (M), mass % ?1.0 Insolubles (I), mass % ?0.4 Unsaponifiables (U), mass % ?2.5 MIU (Totalized), mass % ?3.0 Iodine Value ?118 Flash Point >430 ?F.
(22) TABLE-US-00002 TABLE 2 Compositional Analysis of Exemplary DCO DCO Value Method Analyte Unit Range ASTM D445 @ 25? C. Kinematic Viscosity cSt 35-175 ASTM D 5865-13 Caloric Value cal/100 g 700-1000 AOAC 2005.07 mod. Alpha Carotene mcg/g 0-25 AOAC 2005.07 mod. Total Beta Carotene mcg/g 0-30 AOAC 2005.07 mod. Trans Beta Carotene mcg/g 0-20 AOCS Cc 6-25 Cloud Point ? C. ?15-15 AOCS Cc 13j-97 1 Lovibond Red 0.1-100 AOCS Cc 13j-97 1 Lovibond Yellow 0.1-100 AOCS Cc 10c-95 @ 20? C. Density g/cm {circumflex over ()} 3 0.89-0.92 AOCS Ca 17-01 Arsenic ppm <0.1 AOCS Ca 17-01 Cadmium ppm <0.1 AOCS Ca 17-01 Calcium ppm 0-100 AOAC 937.09 Chlorides % 0.1-0.5 AOCS Ca 17-01 Lead ppm <0.1 AOCS Ca 17-01 Magnesium ppm 0-600 AOCS Ca 17-01 Manganese ppm 0-5 Hydra IIc (AA) Mercury ppm <0.1 AOCS Ca 20-99 Phosphorus ppm 0-300 AOCS Ca 17-01 Potassium ppm 0-200 AOCS Ca 17-01 Sodium ppm 0-600 AOCS Ca 17-01 mod. Sulfur ppm 0-200 GC-FID Ethyl Linoleate mass % 0-10 GC-FID Ethyl Linolenate mass % 0-3 GC-FID Ethyl Oleate mass % 0-5 GC-FID Ethyl Palmitate mass % 0-5 GC-FID Ethyl Stearate mass % 0-3 GC-FID Total Fatty Acid Ethyl Esters mass % 0-17 AOCS Ce 1a-13 Arachidic Acid mg/g 0-10 AOCS Ce 1a-13 Behenic Acid mg/g 0-5 AOCS Ce 1a-13 Eicosenoic Acid mg/g 0-5 AOCS Ce 1a-13 Erucic Acid mg/g 0-2 AOCS Ce 1a-13 Lauric Acid mg/g 0-1 AOCS Ce 1a-13 Lignoceric Acid mg/g 0-5 AOCS Ce 1a-13 Linoleic Acid + Isomers mg/g 400-600 AOCS Ce 1a-13 Linolenic Acid, alpha mg/g 0-30 AOCS Ce 1a-13 Margaric Acid mg/g 0-2 AOCS Ce 1a-13 Margaroleic Acid mg/g 0-2 AOCS Ce 1a-13 Myristic Acid mg/g 0-2 AOCS Ce 1a-13 Oleic Acid + Isomers mg/g 150-350 AOCS Ce 1a-13 Other Fatty Acids mg/g 0-2 AOCS Ce 1a-13 Palmitic Acid mg/g 90-180 AOCS Ce 1a-13 Palmitoleic Acid mg/g 0-3 AOCS Ce 1a-13 Stearic Acid mg/g 50-300 AOCS Ce 1a-13 Tetracosenoic Acid mg/g 0-2 AOCS Cc 9a-48 Flash Point ? F. 400-500 AOCS Ca 14-56 Glycerol % 0.0-0.5 AOCS Cd 11c-93 Diglycerides % 0-10 AOCS Cd 11c-93 Monoglycerides % 0-2 AOCS Cd 11c-93 Triglycerides % 65-90 AOCS Ca 3a-46 Insolubles % 0.0-0.5 AOCS Cd 1d-92 Iodine 110-130 AOCS Ca 2e-84 Moisture (K/F) % 0-2 AOCS Cd 12b-92 OSI hours 0-15 AOCS Cd 18-90 p-Anisidine Value 0-200 AOCS Cd 8b-90 Peroxide meq/kg 0-200 ASTM D97 Pour Point ? C. ?15-10 AOCS Cc 9a-48 Smoke Point ? F. 150-500 AOCS Cc 17-95 Soap as Sodium Oleate ppm 0-10000 USP 40/NF 35 24-methylene-cholesterol % w/w 0.0-0.5 USP 40/NF 35 Brassicaserol % w/w 0.0-0.5 USP 40/NF 35 Campestanol % w/w 0.0-0.5 USP 40/NF 35 Campesterol % w/w 0-1 USP 40/NF 35 Cholesterol % w/w 0.0-0.5 USP 40/NF 35 Clerosterol % w/w 0.0-0.5 USP 40/NF 35 Sitostanol % w/w 0.0-0.5 USP 40/NF 35 Stigmasterol % w/w 0-1 USP 40/NF 35 ?-sitosterol % w/w 0-2 USP 40/NF 35 ?-5,23-stigmastadienol % w/w 0.0-0.5 USP 40/NF 35 ?5,24-stigmasadienol % w/w 0.0-0.5 USP 40/NF 35 ?-5-avenasterol % w/w 0-1 USP 40/NF 35 ?-7-Avenasterol % w/w 0-1 USP 40/NF 35 ?-7-Campesterol % w/w 0.0-0.5 USP 40/NF 35 ?-7-Stigmastenol % w/w 0-1 USP 40/NF 35 Total Sterols % w/w 0-2 AOCS Ce 8-89 Total Tocopherols ppm 0-2000 AOCS Ce 8-89 Total Tocotrienols ppm 0-1000 AOCS Ce 8-89 Total Vitamin E ppm 0-2000 AOCS Ce 8-89 ?-tocopherol ppm 0-1000 AOCS Ce 8-89 ?-Tocotrienol ppm 0-500 AOCS Ce 8-89 ?-tocopherol ppm 0-20 AOCS Ce 8-89 ?-Tocotrienol ppm 0-100 AOCS Ce 8-89 ?-tocopherol ppm 0-1000 AOCS Ce 8-89 ?-Tocotrienol ppm 0-500 AOCS Ce 8-89 ?-tocopherol ppm 0-500 AOCS Ce 8-89 ?-Tocotrienol ppm 0-100 AOCS Ce 1e-91 Trans Fat % 0-1 AOCS Ca 6a-40 Unsaponifiables % 0-3
(23) A rubber formulation (also referred to herein as the rubber composition) typically contains an elastomer (e.g. styrene-butadiene rubber (SBR), ethylene propylene diene monomer (EPDM), natural rubber (NR), nitrile rubber (NBR), etc.) and a process oil.
(24) Different elastomers are contemplated herein, depending on the end use or the desired properties of the rubber formulation: 1,2-butadiene rubber, butyl rubber (IIR), halogenated butyl rubber, acrylonitrile-butadiene rubber (NBR), acrylonitrile-styrene-butadiene copolymer rubber, chloroprene rubber, ethylene-propylene copolymer rubber, styrene-isoprene copolymer rubber, styrene-isoprene-butadiene copolymer rubber, isoprene-butadiene copolymer rubber, chlorosulfonated polyethylene rubber, acrylic rubber, epichlorohydrine rubber, silicone rubber, urethane rubber, and mixtures thereof, alone or in combination of two or more.
(25) Other materials can also be included in the rubber formulation, including for example, filler (e.g. carbon black, silica), activator (e.g. zinc oxide), fatty acid (e.g. stearic acid), antioxidants (e.g. TMG), curative (e.g. sulfur), and accelerator (e.g. TBBS, TMTD, DPG). A filler can be present in the formulation in an about from about 20 PHR to about 100 PHR. An activator can be present in the formulation in an amount from about 1 PHR to about 10 PHR. An antioxidant can be present in an amount from about 0.1 PHR to about 5 PHR. A curative can be present in an amount from about 0.1 PHR to about 3.0 PHR, or about 1.0 PHR to about 2.0 PHR. An accelerator can be present in an amount from about 0.1 PHR to about 3.0 PHR.
(26) Additional ingredients may be included to adjust the properties of the rubber compound, for example, to change how the rubber vulcanizes (power consumption, scorch time, cure time, etc.) or to adjust the final rubber compound characteristics.
(27) As described herein, the process oil comprises distiller's corn oil, in whole or in part, for example, corn oil extracted from whole stillage after fermentation or separated from fermentation residue. Exemplary corn oil includes post fermentation distiller's corn oil or post distillation distiller's corn oil. Distiller's corn oil can be added to the rubber formulation in an amount from about 2 to about 40 parts per hundred rubber (PHR), for example, about 2 to about 20 PHR, about 2 to about 10 PHR, about 20 to about 40 PHR, about 30 to about 40 PHR, about 10 to about 30 PHR, or about 20 to about 30 PHR, and any ranges falling therein. The distiller's corn oil can have an iodine value of at least 100 and at most 200.
(28) In addition, the distiller's corn oil can contain a low fatty acid alkyl esters (e.g. fatty acid ethyl esters), for example less than about 16%, or less than about 10%, or less than about 5%, or less than about 2%, or less than about 1%, or less than about 0.5% free fatty acid alkyl ester.
(29) Other process oils having similar or synergetic properties can be used in combination with the distiller's corn oil, including for example, other vegetable oils such as soybean oil, olive oil, cotton seed oil, rape seed oil, corn oil, sesame oil, safflower oil, linseed oil, etc. Likewise, it can be desirable to add aromatic oil, naphthenic oil and/or paraffin oil in addition to the distiller's corn oil.
(30) Production of the rubber compound can occur according to known methods. See Example 2 and Table 4 below. Master batch mixing allows proper mixing and distribution of each component at high temperature before the curative is added. A typical master batch mixing begins with a temperature sweep at 220? F., followed by a 280? F. sweep, and drop at 300? F. A final pass mix is performed similar to master batch mixing except that the sulfur curative is added. A typical final pass mix is carried out by mixing at 180? F., then dropping once the temperature reaches 220? F. A typical vulcanization is carried out when temperature of the final formulation reaches 290? F. or higher. A typical process to drive vulcanization is at 320? F. for 17 minutes.
(31) Slight differences in production are contemplated, such as performing the compounding in one step or adjusting one or more of the temperature settings.
(32) A process for formulating rubber can comprise: (i) combining an elastomer with a process oil comprising corn oil having an FFA content greater than 4% w/w of the total corn oil and FAAE content less than 16% w/w of the total corn oil, a filler, an activator, and an antioxidant; (ii) mixing the components from (i) at a temperature of at least about 210? F. to form a master batch; (iii) adding a sulfur curative to the master batch; and (iv) mixing the sulfur curative and master batch at a temperature of at least about 180? F. to form a final pass mix. The process can further comprise (v) vulcanizing the final pass mix at a temperature of at least about 290? F. for at least 10 minutes.
(33) Ultimately, incorporating DCO improves the performance of the rubber compounds in a number of evaluations including: tensile strength, elongation, modulus, heat aging, tear properties, DIN abrasion, and DeMattia flex resistance (
(34) Depending on the chosen elastomer and specific formulation, the resulting rubber compound can be used for various applications. SBR rubber compounds are characterized by abrasion and heat resistance as well as low temperature flexibility. SBR rubber is typically used in pneumatic tires and conveyor belts. EPDM rubber compounds are characterized by resistance to oxygen, UV rays, and water damage. EPDM rubber is used in roofing membranes, hoses, seals, etc.
(35) While the invention has been particularly shown and described with reference to a number of embodiments, it would be understood by those skilled in the art that changes in the form and details may be made to the various embodiments disclosed herein without departing from the spirit and scope of the invention and that the various embodiments disclosed herein are not intended to act as limitations on the scope of the claims.
EXAMPLES
(36) The following examples are provided such that those of ordinary skill in the art have a complete disclosure and description of how to implement the methods disclosed herein. Efforts have been made to ensure accuracy with respect to numbers used (e.g., amounts, temperature, etc.) but some experimental errors and deviations should be accounted for. Unless indicated otherwise, parts are by weight, molecular weight is average molecular weight, and pressure is at or near atmospheric.
Example 1: Exemplary Rubber Formulations
(37) Five rubber formulations using distiller's corn oil, naphthenic oil, and soybean oil were prepared according to materials listed in Table 3. Inclusions of the distiller's corn oil and soybean oil were selected to equalize the durometer hardness of rubber compound made with Calsol 8240 (naphthenic oil). The rest of the components (SBR 1502, N550, zinc oxide, stearic acid, TMQ, sulfur RM, TBBS, and TMTD) were kept consistent with all the samples. The inclusion of each component is based upon parts per hundred rubber (PHR).
(38) TABLE-US-00003 TABLE 3 Materials for Rubber Formulations Sample Name Raw Material DCO DCO DCO Type Trade Name NO 1 2 3 SBO Elastomer SBR 1502 100 100 100 100 100 Cabon black Filler N550 50 50 50 50 50 NO Calsol 8240 25 DCO 1 20 DCO 2 20 DCO 3 20 SBO 20 Activator Zinc Oxide 5 5 5 5 5 Fatty acid Stearic acid 1.5 1.5 1.5 1.5 1.5 Antioxidant TMQ 1 1 1 1 1 Curative Sulfur TM 0.8 0.8 0.8 0.8 0.8 Accelerator TBBS 1.5 1.5 1.5 1.5 1.5 Accelerator TMTD 0.5 0.5 0.5 0.5 0.5 Abbreviations are as follows: NOnaphthenic oil; DCO 1/2/3distiller's corn oil samples 1/2/3; and SBOsoybean oil.
Example 2: Mixing Data of Rubber Formulations
(39) The power consumption, mixing speed, temperature, and time for both master batch and final mixes are listed. For the master batch mixes, SBR and one half of the carbon black N550 were added to the other components (except the sulfur curative) and allowed to mix for one minute at which point the remainder of the carbon black N550 was added. A temperature sweep at 220? F. and 280? F. were carried out followed by drop at 300? F. Final pass mix was formulated with the material from the master batches along with addition of the sulfur curative. The samples were mixed at 180? F., then dropped once the temperature reached 220? F. Vulcanization of the compounds was carried out at 320? F. for 17 minutes in the slab or plaque molds for the corresponding tests.
(40) TABLE-US-00004 TABLE 4 Mixing Data of Rubber Formulations Average Integrated Time Temperature Power Speed Power Power Batch (min) (? F.) (HP) (rpm) (HP) (HP * min) Master Batch NO 7.70 300 16.4 109.2 16.48 114.93 DCO 1 5.47 300 14.27 101.52 14.35 77.33 DCO 2 5.15 300 14.12 99.84 14.05 71.30 DCO 3 5.37 300 12.17 95.08 13.09 69.81 SBO 4.98 300 7.34 67.38 10.35 62.05 Final Batch NO 1.55 220 9.44 66.32 9.4 18.96 DCO 1 1.75 221 7.66 55.83 8.55 19.13 DCO 2 1.78 220 8.36 57.95 8.95 18.97 DCO 3 1.65 222 9.75 62.67 9.67 18.43 SBO 1.47 220 8.17 56.52 8.88 15.94
(41) The power consumption, mixing speed, temperature, and time for both master batch and final mixes are listed in Table 4. For the master batch mixes, SBR and one half of the carbon black N550 were added to the other components (except the sulfur curative) and allowed to mix for one minute at which point the remainder of the carbon black N550 was added. A temperature sweep at 220? F. and 280? F. were carried out followed by drop at 300? F. Final pass mix was formulated with the material from the master batches along with addition of the sulfur curative. The samples were mixed at 180? F. and dropped once the temperature reached 220? F.
Example 3: Vulcanization Using Rotorless Cure Meter
(42) Rubber formulations were allowed to cure in a Montech upgraded MDR-2000 for 30 minutes at 350? F. with 0.50 arc according to ASTM D 5289. The following are listed in Table 5: the minimum (ML) and maximum torque (MH) measured in pounds force per inch, cure times (T50, T90), and scorch time (TS1) measured in minutes.
(43) TABLE-US-00005 TABLE 5 Vulcanization Using Rotorless Cure Meter Min. Cure Sample Torque, Cure Time, Time, Scorch Time, Max. Torque, Name ML, lbf-in T50, min T90, min TS1, min MH, lbf-in NO 0.63 6.93 12.22 5.24 7.29 DCO 1 0.77 6.36 11.67 4.83 7.59 DCO 2 0.75 6.70 12.38 5.05 7.77 DCO 3 0.79 6.56 12.12 4.91 7.74 SBO 0.77 6.30 11.04 4.89 7.25
(44) Results demonstrate rubber formulations comprising vegetable oil have higher minimum and maximum torque, shorter cure times, and shorter scorch times.
Example 4: Characterizing Original Rubber Formulations Containing Vegetable Oils
(45) The Shore A Durometer points, tensile strength (psi), ultimate elongation (%), and modulus (50%, 100%, 200%, and 300%) were measured according to ASTM D412 and ASTM D2240e1 and are listed in Table 6 and shown in
(46) TABLE-US-00006 TABLE 6 Rubber Compound Properties Sample Name NO DCO 1 DCO 2 DCO 3 SBO Shore A Durometer (points) 51 52 52 52 52 Tensile Strength (psi) 2481 2346 2467 2566 2404 Ultimate Elongation (%) 670 678 721 746 741 50% Modulus (psi) 122 116 118 119 116 100% Modulus (psi) 204 199 200 193 185 200% Modulus (psi) 517 523 526 491 451 300% Modulus (psi) 946 942 941 889 813
(47) Durometer indicates the overall hardness of the rubber compounds measured in points. The PHR inclusion of the vegetable oils and naphthenic oil were adjusted to control for similar hardness level of each produced rubber compound. As shown in Table 6, the durometer hardness levels of each sample are nearly identical. The tensile strength and ultimate elongation differences of each sample are shown in
(48) The tensile strength is measured as the maximum force incurred before breaking.
(49) The ultimate elongation is the maximum length stretched over the original length measured as a percent.
(50) Tear resistance is the force required to initiate a tear in a piece of rubber and is measured in pounds of force per inch (lbf/in) according to ASTM D624-00 (2012).
Example 5: Properties of Heat-Aged Rubber Compounds Containing Distiller's Corn Oil
(51) Rubber compounds were heat-aged at 212? F. for 70 hours in an air oven per ASTM D573. Property tests were performed as previously mentioned.
(52)
(53) In addition, percent change in tensile strength and ultimate elongation were determined for each aged rubber compound compared to the original.
Example 6: Compression Tested Rubber Formulations
(54) Rubber compounds were compressed for 22 hours at 100? C. at 25% deflection and allowed a half hour for recovery. The percent compression was calculated as the final thickness over the original thickness to assess any permanent deformation. Rubber formulations containing DCO exhibited between 29% and 31% compression set, which was greater than both NO and SBO containing formulations as shown in
Example 7: DIN Abrasion Testing
(55) The volumetric loss of rubber formulations was measured after exposure to an abrasive rotating cylinder.
Example 8: Crosslink Density Testing
(56) The crosslink density of the rubber compounds were assessed according to ARDL 3135. The samples were immersed in toluene for 24 hours at room temperature. The crosslink density (Ve) was calculated according to the Flory-Rehner equation using the polymer-interaction constant for polychloroprene in toluene (0.35). See
Example 9: Compositional Analysis of Distiller's Corn Oil and Soybean Oil
(57) Composition of DCO1, DCO2, DCO3, and SBO were determined. Compositional analysis includes free fatty acid, fatty acid ethyl ester, iodine value, fatty acid profile, and mineral profile. See Table 7.
(58) The Demattia flex of the rubber compounds was measured according to ASTM D430 at 300 CPM on unpierced specimens tested up to 1,000,000 cycles. The samples were exposed to repetitive flexing and the length of any formed cracks were measured throughout the testing. As shown in
(59) TABLE-US-00007 TABLE 7 Composition of DCOs and SBO Sample Name Component DCO1 DCO2 DCO3 SBO Free Fatty Acid (% w/w) 4.89% 7.88% 10.99% 1.35% Fatty Acid Ethyl Ester (% w/w) 15.84% 10.45% 3.59% 0.28% Iodine Value 121.99 121.5 120.9 128.53 Fatty Acid Profile.sup.a Palmitic 13.2% 14.7% 14.7% 13.3% Stearic 1.9% 2.1% 2.1% 5.6% Oleic 27.6% 29.6% 29.1% 22.3% Linoleic 55.9% 52.4% 52.9% 50.2% Linolenic 1.4% 1.2% 1.1% 8.5% Total 100.0% 100.0% 100.0% 100.0% Mineral Profile Calcium 2.3 27 <1 34 Magnesium 7.6 198 1 41 Phosphorous 5.5 127 3 453 Potassium 2.5 40 4 243 Sodium 1.5 110 4 <2 .sup.aPercentage of each fatty acid based upon peak area obtained via GC-FID
Example 10: Compositional Analysis of Distiller's Corn Oil with High or Low Fatty Acid Ethyl Esters
(60) Composition of high free fatty acid/low fatty acid ethyl ester (HFFA/LFAEE) and high free fatty acid/high fatty acid ethyl ester (HFFA/HFAEE) distiller's corn oils were also determined. Compositional analysis includes free fatty acid (FFA) and fatty acid ethyl ester (FAEE) content. See Table 8.
(61) TABLE-US-00008 TABLE 8 Composition of DCOs with High Free Fatty Acid and High or Low Fatty Acid Ethyl Ester Compositions Sample Name Component HFFA/LFAEE HFFA/HFAEE Free Fatty Acid (% w/w) 59.50% 42.04% Fatty Acid Ethyl Ester (% w/w) 0.17% 37.98%
(62) Table 9 provides the Demattia flexibility of DCO rubber formulations containing high free fatty acid and high/low fatty acid ethyl ester formulations. The compositions containing the low fatty ethyl esters performed better than the NO formulation and the DCO formulation with high fatty acid ethyl ester.
(63) TABLE-US-00009 TABLE 9 Demattia Flexibility of Rubber Compounds Made with High Free Fatty Acid and High or Low Fatty Acid Ethyl Ester Compositions Compared to Naphthenic Oil Sample Result NO 1 of 3 went to 1,000,000 cycles HFFA/LFAEE 3 of 3 went to 1,000,000 cycles HFFA/HFAEE 1 of 3 went to 1,000,000 cycles
Example 11: Testing of Distiller's Corn Oil Rubber Formulations with High or Low Fatty Acid Ethyl Esters
(64) Original tensile strength, ultimate elongation, and tear resistance was determined for rubber formulations made with high free fatty acid and high or low fatty acid ethyl ester compositions compared to NO rubber formulations. See