The present Invention' relates to a method of preparing reduced grapheme oxide, Incorporation of the adduced graphene oxide into polyisoprene latex to provide a polyisoprene latex graphene composite and elastomerk articles prepared using the polyisoprene latex-graphene composite. In particular, the reduction of-graphene oxide is accomplished without the use of strong reducing agents and organic solvents and incorporation of die reduced graphene oxide into polyisoprene latex Is accomplished using room temperature latex mixing method or hot maturation. The resultant composite exhibits good colloid stability and polyisoprene latex films produced from the composite exhibit good mechanical properties with improved ageing resistance.

An extruder is disclosed including: a barrel; and a screw provided with a helical groove; wherein the screw comprises a dewatering portion comprising a first portion, and a second portion at a location downstream from the first portion; wherein, at the dewatering portion, clearance between the groove and the barrel decreases as one proceeds downstream; and wherein clearance reduction ratio at the first portion is greater than clearance reduction ratio at the second portion.

A masterbatch manufacturing method is disclosed in which carbon black is added to a liquid and this is agitated to obtain a carbon black slurry; the carbon black slurry and rubber latex are mixed to obtain pre-coagulation rubber latex; and the pre-coagulation rubber latex is coagulated; wherein, at the operation in which the carbon black slurry is obtained, dispersion time from the start of agitation to the end of agitation is not less than 5 times, but not greater than 40 times. A particle diameter reduction relaxation time v may be found by plotting measurement results on a planar graph in such fashion that elapsed time t (minutes) since the start of agitation is plotted on the horizontal axis, and particle diameter f (m) of carbon black is plotted on the vertical axis, to obtain a best-fit solution.

A method for producing a wet rubber comprises a step (I) of dispersing the filler into the dispersing solvent, and adding, at the time of the dispersing, at least one portion of the rubber latex solution to the dispersing solvent to produce a slurry solution containing the filler to which particles of the rubber latex adhere, a step (II) of mixing the slurry solution containing the filler, to which the rubber latex particles adhere, with the rest of the rubber latex solution to produce a rubber latex solution containing the filler, to which the rubber latex particles adhere, and a step (III) of solidifying and drying the rubber latex solution containing the filler. About the filler, the ratio of the nitrogen adsorption specific surface area (N.sub.2SA) thereof to the iodine adsorption amount (IA) thereof ((N.sub.2SA)/(IA)) is 1.00 or more.

A method for producing a rubber wet master batch using, as raw materials, at least a rubber powder, a filler, a dispersing solvent, and a rubber latex solution, comprises a step (I) of adding, at a time of dispersing the rubber powder in the dispersing solvent, at least one portion of the rubber latex solution to the dispersing solvent to produce a rubber powder solution containing the rubber powder to which rubber latex particles adhere, a step (II) of adding the filler to the rubber powder solution, and mixing the solution and the filler with each other to produce a rubber-powder-containing slurry solution, and a step (III) of mixing the rubber-powder-containing slurry solution with a rest of the rubber latex solution, and then solidifying/drying the resultant mixture.

The present invention discloses a molded article having a surface feature created by a light reactive agent interacting with light from a light source, and a method for making the same. The article is molded from a slurry comprised of an aqueous solution that includes a plurality of fibers and a light reactive agent. The slurry is molded into a three-dimensional solid fibrous molded part. The solid fibrous molded part is exposed to a light source such that the light reacts with the light reactive agent to create at least one surface feature. The surface feature can be, for example, a texture or a color change.

A process comprises a step (iii) of dehydrating a filler-containing rubber solidified product to produce the tire member. The step (iii) is a step of adding, into the filler-containing rubber solidified product, a compound represented by formula (I):

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wherein R.sup.1 and R.sup.2 each represent a hydrogen atom, and an alkyl group, alkenyl group or alkynyl group that has 1 to 20 carbon atoms and R.sup.1 and R.sup.2 may be the same as or different from each other, and M.sup.+ represents a sodium ion, potassium ion or lithium ion, and dispersing the compound represented by the formula (I) into the filler-containing rubber solidified product, which contains water, while dehydrating the filler-containing rubber solidified product.

Provided is a rubber member that can, when used in a rubber article such as a tire, improve the on-ice performance of the rubber article. A rubber member comprises a nanomaterial, wherein the nanomaterial has a major axis of less than 100 nm in the case of being non-fibrous or a minor axis length of less than 100 nm and a major axis length of less than 1000 nm in the case of being fibrous, and has a content of a polar group of 100 mg/kg or more.

As a rubber composition excellent in fatigue resistance and a method for producing the same, this disclosure provides a rubber composition containing a zinc oxide, wherein: a total volume of aggregates of the zinc oxide with a diameter of 20 m or more is 0.008 or less in the rubber composition by volume fraction; and a method for producing the rubber composition, comprising: preparing a wet masterbatch by using a carbon black with a surface average acidic functional group amount (eq/m.sup.2) of 0.15 or more and less than 3.00, preferably 0.40 or more and less than 1.50; and compounding a zinc oxide with the wet masterbatch.

This invention relates generally to vulcanization compounds and relates more specifically to vulcanization compositions with reduced allergenic potential that include accelerator compositions for vulcanizing elastomeric articles. Vulcanization compositions are disclosed that include a single fugitive dihydrocarbyl xanthogen polysulfide accelerator and a single aldehyde-aniline condensate accelerator.