A process for producing a wet rubber masterbatch comprises a step (I) of dispersing a filler into a dispersing solvent to produce a filler-containing slurry solution, and a step (II) of adding a rubber latex solution to the filler-containing slurry solution to yield a filler-containing rubber latex solution, and stirring the yielded filler-containing rubber latex solution while heating the filler-containing rubber latex solution, thereby solidifying the filler-containing rubber latex solution, and a step (III) of stirring the resultant while adding an acid thereto, thereby solidifying the filler-containing rubber latex solution. In the step (II), the circumferential speed of a stirring impeller which a mixing tank used at the time of the stirring has is less than 10 m/s, and a calorie of 25 to 250 J both inclusive per unit period and unit mass is given to the filler-containing rubber latex solution by the heating.

The present invention relates to a non dusty polymer powder composed of aggregated latex particles prepared by a multistage preparation process.

A method for producing a wet rubber masterbatch uses a single-screw extruder. The single-screw extruder includes a screw, and an external cylinder in which a slit extended along the length direction of the external cylinder (the screw-shaft direction) is formed in an internal wall surface of the external cylinder, and when the width of the slit is represented by A and the clearance between a crest of the screw and the internal wall surface of the external cylinder is represented by B, the following expression (1) is satisfied:

0<AB(Y)/AB(X)<0.9(1)

wherein AB (Y) is the product of A and B at a downstream side along the screw-shaft direction of the external cylinder, and AB (X) is the product of A and B at an upstream side along the screw-shaft direction of the external cylinder.

Edge separation in a turned-up end portion (5E) of a carcass ply (5) is suppressed. In a pneumatic tire comprising a bead core (4) embedded in a bead portion (3) and a carcass ply (5) turned up and locked around the bead core (4), a rubber sheet (10) is prepared using a wet masterbatch containing natural rubber and/or polyisoprene rubber and carbon black, and the rubber sheet (10) is arranged on at least one of front and back sides of the turned-up end portion (5E) of the carcass ply (5).

This invention relates to an elastomeric article with improved lubricity and donnablity and reduced stickiness/tackiness. According to the methods of the invention, the internal surface of the elastomeric article is coated with a polyisoprene coating. The coating of the invention is formed from synthetic polyisoprene rubber that may or may not contain minor amounts of other components. The coating is preferably directly bonded to the underlying elastomeric article.

A laminate having high ozone crack resistance and excellent in flexibility and fatigue resistance is provided. The laminate includes: a coating film 12 containing modified polyvinyl alcohol grafted by a functional group that is linear-chain, cycloaliphatic, branched, or aromatic and has a molecular weight of 20 to 10000; and a rubber layer 11 in contact with the coating film 12.

The present invention relates to a process for making a polymer masterbatch with silica nanoparticles highly uniformly dispersed therein by using a stable aqueous emulsion of compatibilized silica nanoparticles, the sizes of which are mechanically reduced to nanoscales. Adequate reduction of the silica particles to nanoscales is essential for the formation of a desired emulsion of highly stability. The said emulsion of compatibilized silica nanoparticle can be easily mixed under mild conditions with a polymer in latex form, which can be high purity natural rubber, synthetic rubber and/or a blend thereof. The bifunctional organosilane coupling agent bonded-Silica nanoparticles are subsequently incorporated into the rubber polymer network during coagulation with formic acid. The inventive rubber-silica masterbatch thus obtained is useful for manufacturing rubber and other polymer composite products.

The invention relates to a process for the preparation of a masterbatch of diene elastomer and reinforcing inorganic filler in accordance with the invention comprises the following successive stages: bringing into contact and mixing one or more aqueous dispersions (B) of one or more hydrophobized reinforcing inorganic fillers, which coagulate(s) spontaneously with the said latex, and one or more diene elastomer latexes (A) in order to obtain a coagulum, without requiring a coagulating agent, recovery of the coagulum, then drying the recovered coagulum in order to obtain the masterbatch.

In an embodiment, a natural rubber-based ABStarget polymer blend includes natural rubber-based ABS powder combined with a set of target polymers (e.g., polycarbonate (PC)). A natural rubber-based ABS powder production process includes producing grafted natural rubber; and mixing the grafted natural rubber with a set of grafted polybutadiene rubbers. The set of grafted polybutadiene rubbers includes at least one grafted polybutadiene rubber having a particle size that is significantly different than the grafted natural rubber particle size. In an embodiment, the grafted natural rubber exhibits a large particle size; a first grafted polybutadiene rubber exhibits a small particle size; and a second grafted polybutadiene rubber exhibits a medium particle size between the large and small particle sizes. Natural rubber-based ABStarget polymer blends in accordance with the present disclosure can exhibit generally equivalent or increased impact and/or tensile strength compared to other non-natural or synthetic rubber-based ABS blends.

The present disclosure provides for a process for manufacturing of dipped latex products without using any animal derived ingredients and dipped latex products produced by said process. The disclosed process successfully over comes drawbacks of drop in product yield (due to coagulum formation) and burst pressures caused by absence-of casein in latex formulation. Therefore, the dipped latex products so produced through the process have final composition similar to that of any other dipped latex products with casein except for absence of casein and having 0.8 phr of Sulphur as against 0.6 phr of Sulphur in routine manufacturing. The products also exhibit physical properties similar to that of any other dipped latex products with casein, such as burst pressure and burst volume.