Abstract: The present invention relates to an integrated process for processing and utilizing every part of the guayule plant (Parthenium argnetatum) which comprises the following steps in sequence: separating the stem and branches from the leaves of said plant with a mechanical treatment; treating the leaves to produce waxes and essential oils, and a fraction containing cellulose, hemicellulose (carbohydrates) and, to a minor extent, salts, organic compounds and lignin; extracting from the stem and branches a liquid phase, so forming a first solid woody residue, indicated with bagasse in the present text; treating said first solid woody residue to prepare sugars, resin, rubber and lignin.

Abstract: Disclosed is a method and apparatus for the extraction of high molecular weight biopolymers from plants. Specifically, invention described herein relates to the commercial processing of plant material, including that from desert plants native to the southwestern United States and Mexico, such as the guayule plant (Parthenium argentatum), for the extraction of biopolymers, including natural rubbers. More specifically, the invention relates to laboratory to commercial scale extraction of high molecular weight biopolymers from plant materials including the chemical and mechanical processing of the plants and purification of the extracted biopolymer.

Abstract: The present disclosure provides for a method of rapid expanded solvent extraction of biopolymers, such as rubber, from plant materials, such as guayule, using an expanded hexane solvent. As is illustrated herein, the use of the expanded hexane solvent results in a markedly more efficient and rapid extraction process over other supercritical carbon dioxide extraction systems, including those systems using a hexane cosolvent.

Abstract: A method for the extraction, separation, fractionation and purification of biopolymers from plant materials using supercritical and/or subcritical solvent extractions is disclosed. Specifically, the process can be used for the separation of resins and rubber from guayule shrub (Parthenium argentatum), and other rubber and/or resin containing plant materials, using supercritical solvent extraction, for example supercritical carbon dioxide extraction. Additionally, polar and/or non-polar co-solvents can be used with supercritical carbon dioxide to enhance the selective extraction of resins and rubbers from the shrub.

Abstract: The present invention provides a rubber composition that improves processability and fuel efficiency without decreasing mechanical strength and abrasion resistance, which are excellent properties of natural rubber, and a pneumatic tire using the rubber composition for a tire tread. Specifically, the present invention provides a rubber composition for a tire tread comprising 5 to 150 parts by weight of silica having nitrogen-adsorbing specific surface area of 100 to 300 m2/g and/or 5 to 150 parts by weight of carbon black having nitrogen-adsorbing specific surface area of at least 70 m2/g and dibutyl phthalate oil absorption of at least 70 ml/100 g, based on 100 parts of a rubber component containing 5 to 100% by weight of a deproteinized natural rubber having a weight average molecular weight of 1,400,000 and nitrogen content of at most 0.1% by weight, and a pneumatic tire comprising the rubber composition for a tire tread.

Abstract: Water-swellable hydrophilic polymers are prepared by neutralization of the acidic hydrogel having a degree of neutralization of 0-40 mol % to an ultimate degree of neutralization of 60-85 mol % by mixing with a neutralizing agent in a mincer comprising a system of screw, rotating blade, restricted flow zone and breaker plate, wherein the mincer has a power output of from 1000 to 6000 Wh/m3 the hydrogel passes through a zone having-an energy dissipation density of from 400 to 800 W/1 of mixing volume the average residence time of the hydrogel in the mincer is from 5 to 30 seconds the breaker plate has an open area of from 20 to 40%.

Abstract: A method for extracting polyisoprenes from cells, comprising the steps of contacting the cells with an organic protein-denaturing compound, rupturing the cells to release the polyisoprene from the cells and recovering the polyisoprene. The preferred protein denaturing compound comprises an aqueous solution of a guanidine salt.

Abstract: A stabilizing composition and process for guayule type rubbers which can be directly applied to guayule-type plants or shrubs before processing thereof, or to guayule-type rubber miscella, rubber-resin miscella, etc., contains a volatile low melting point antioxidant which is either liquid or solid and an optional liquid inert carrier which lowers the melting point of the antioxidant. Since antioxidants are generally expensive, recovery thereof as by distillation is aided through the utilization of low boiling point antioxidants.

Abstract: A hydrocarbon insoluble polar fraction is extracted from guayule-like resins by adding a hydrocarbon solvent containing a small amount of water therein to the guayule-like resins and mixing the same. A two-phased solution is formed with the hydrocarbon insoluble polar fraction being located in the water phase. The addition of water to the hydrocarbon increases the yield of the insoluble polar fraction as well as the acid number and the amount of ketoalcohol located therein.

Abstract: A process for achieving a high yield of rubber and/or resin from rubber containing plants such as guayule plants by crushing the plants, forming a slurry with a solvent and fine grinding said slurry with a high shear mixer. The time required by the process is very short in comparison with prior art techniques.

Abstract: A process for extracting rubber and/or resin from rubber containing plants such as guayule utilizing a monophase mixture of an organic polar solvent and a hydrocarbon solvent.

Abstract: A process for extracting resin and rubber from guayule plants utilizing a portion of recycled miscella and a fresh solvent system. An expression step is applied to the plants to enhance recovery of resin and rubber extract. The solvent system is preferably an organic polar solvent and a hydrocarbon solvent for rubber for simultaneous resin and rubber extraction containing at least 50% by weight of the hydrocarbon solvent. The process can be a one-step method wherein resin and rubber are generally simultaneously extracted.

Abstract: A method and composition are disclosed wherein guayule rubber is fractionated into desirable weight average molecular weight fractions by a desired solvent system. Oftentime, a plurality of fractionating steps is utilized wherein the desirable molecular weight rubber fraction is precipitated or extracted. High weight average molecular weight rubbers having usually less than 4% by weight of resin content therein are generally desirable because of their favorable physical properties.

Abstract: Guayule-type resins are chemically treated with an amine terminated polyether. The polyether treated guayule resins have high softening points and usually impart improved physical properties when used as rubber additives.

Abstract: Guayule resin is sulfurized such that it has a high softening point of at least 70.degree. C. The sulfurized guayule resin can be utilized in association with conventional rubbers and the end results in improved properties such as reduced hysteresis loss, increased tensile strength and the like.

Abstract: A process and product thereof for densifying guayule shrubs by compression and forming a densified pellet. The densified pellet substantially maintains its molecular weight during storage over a period of weeks without the aid of any inert gas blanket or the like.

Abstract: Guayule-type resins are chemically treated with polyamine. The resulting composition is suitable as a rubber additive since it improves various physical properties of rubber compositions such as green strength, building tack, tear strength, hysteresis loss and the like.

Abstract: A method for separating guayule bagasse from a guayule-solvent mixture utilizing a monophase solvent. Upon the addition of water, a two-phase system is formed wherein the bagasse is located just below the monophase solvent-water interface.

Abstract: Combinations of para-phenylene diamines and para di(nitroso) arenes act synergistically in guayule rubber-based compositions to protect them against oxidative degradation. A typically useful diamine is N-(1,3-dimethylbutyl)-N'-phenyl-phenyl-p-phenylene diamine and a useful arene is para-di(nitroso)benzene. Vulcanizable compositions, as well as articles made therefrom, are within the scope of the invention.

Abstract: Elastomers such as guayule rubber is stabilized by the addition of an alkyl, cycloalkyl or alkyl substituted cycloalkyl phenyl-phenylenediamine compound with an alkyl, cycloalkyl or alkyl substituted cycloalkyl phosphite compound which, in combination, yield an unexpectant and synergistic result.

Abstract: A method of storing guayule and guayule-like plant material prior to processing which comprises mixing the material in communited form with at least one essentially water-free organic liquid to form a slurry in which the material is protected from contact with oxygen and storing said slurry for at least about 24 hours is disclosed. Preferably, the organic liquid is an alcohol, ether, ester, ketone, or hydrocarbon and optionally the slurry also contains an oxidation stabilizer.

Abstract: Rubber, hydrocarbons, i.e., resins, and other useful by-products are extracted from shrubs such as guayule and guayule-like shrubs by a procedure wherein the shrub, after being comminuted, is processed in an aqueous and/or a non-aqueous system. An optional water treatment step can be used to remove water solubles and/or facilitate processing and achieve increased yield of desired by-products.

Abstract: Rubber, hydrocarbons, i.e., resins, and other useful by-products are extracted, recovered and isolated from shrubs such as guayule and guayule-like shrubs by a procedure wherein the entire non-defoliated shrub, after being comminuted, is processed in an aqueous and/or a non-aqueous system. An optional water treatment step can be used to remove water solubles and/or facilitate processing and achieve increased yield of desired by-products.