In a first aspect, the present invention is directed to a rubber composition comprising 70 phr to 90 phr of styrene butadiene rubber, wherein said styrene butadiene rubber comprises a first styrene butadiene rubber having a glass transition temperature within a range of −49° C. to −15° C. and a second styrene butadiene rubber having a glass transition temperature within a range of −50° C. to −89° C. Furthermore, the rubber composition comprises from 10 phr to 30 phr of one or more of natural rubber and synthetic polyisoprene rubber, 100 phr to 200 phr of silica, and at least 25 phr of at least one terpene resin having a weight average molecular weight (Mw) of at most 1000 g/mol. Moreover, the invention is directed to a tire comprising such a rubber composition, in particular in the tread of the tire.

The present application provides a dispersion dispersed satisfactorily cellulose nanofibers, powdery cellulose nanofibers obtained by pulverizing thereof, a resin composition obtained by blending thereof and a molding raw material for a 3D printer by using thereof. It is possible to obtain a composition uniformly finely dispersed the cellulose nanofibers by treating a mixture containing unmodified cellulose nanofibers and a dispersant using a high speed agitating Medialess disperser, and followed by pulverizing the composition to blend with a resin and a rubber component. Also, a resin composition improved in mechanical properties and heat resistance, obtained by blending the powdery cellulose nanofibers above with a thermoplastic resin or a thermosetting resin, is useful as a molding material for a 3D printer.

The present application provides a dispersion dispersed satisfactorily cellulose nanofibers, powdery cellulose nanofibers obtained by pulverizing thereof, a resin composition obtained by blending thereof and a molding raw material for a 3D printer by using thereof. It is possible to obtain a composition uniformly finely dispersed the cellulose nanofibers by treating a mixture containing unmodified cellulose nanofibers and a dispersant using a high speed agitating Medialess disperser, and followed by pulverizing the composition to blend with a resin and a rubber component. Also, a resin composition improved in mechanical properties and heat resistance, obtained by blending the powdery cellulose nanofibers above with a thermoplastic resin or a thermosetting resin, is useful as a molding material for a 3D printer.

A rubber composition, which exhibits an improved fatigue strength and stiffness performance compromise, is based on at least one elastomer matrix containing at least one polyisoprene and at least one copolymer containing ethylene units and diene units; a paraffin oil having a glass transition temperature of less than -75° C.; a reinforcing filler comprising carbon black; and a crosslinking system, in which the at least one polyisoprene and the at least one copolymer containing ethylene units and diene units represent more than 40% by weight of the elastomer matrix.

A rubber composition, which exhibits an improved fatigue strength and stiffness performance compromise, is based on at least one elastomer matrix containing at least one polyisoprene and at least one copolymer containing ethylene units and diene units; a paraffin oil having a glass transition temperature of less than -75° C.; a reinforcing filler comprising carbon black; and a crosslinking system, in which the at least one polyisoprene and the at least one copolymer containing ethylene units and diene units represent more than 40% by weight of the elastomer matrix.

A rubber composition, which exhibits an improved fatigue strength and stiffness performance compromise, is based on at least one elastomer matrix containing at least one polyisoprene and at least one copolymer containing ethylene units and diene units; a paraffin oil having a glass transition temperature of less than -75° C.; a reinforcing filler comprising carbon black; and a crosslinking system, in which the at least one polyisoprene and the at least one copolymer containing ethylene units and diene units represent more than 40% by weight of the elastomer matrix.

The invention relates to a process which responds to this problem scenario. The invention therefore relates to a process for preparing a rubber composition based on at least one diene elastomer, a reinforcing filler, a crumb rubber and a crosslinking system, said process comprising at least the following steps: incorporating the reinforcing filler into the diene elastomer, all at once or in several stages, and mixing; when the temperature of the mixture reaches a temperature of greater than 100° C., adding the crumb rubber; continuing the mixing up to a maximum temperature of between 120° C. and 190° C.; cooling the mixture to a temperature of less than 100° C.; incorporating the crosslinking system and mixing up to a maximum temperature of less than 110° C.

The invention relates to a process which responds to this problem scenario. The invention therefore relates to a process for preparing a rubber composition based on at least one diene elastomer, a reinforcing filler, a crumb rubber and a crosslinking system, said process comprising at least the following steps: incorporating the reinforcing filler into the diene elastomer, all at once or in several stages, and mixing; when the temperature of the mixture reaches a temperature of greater than 100° C., adding the crumb rubber; continuing the mixing up to a maximum temperature of between 120° C. and 190° C.; cooling the mixture to a temperature of less than 100° C.; incorporating the crosslinking system and mixing up to a maximum temperature of less than 110° C.

The invention relates to a process which responds to this problem scenario. The invention therefore relates to a process for preparing a rubber composition based on at least one diene elastomer, a reinforcing filler, a crumb rubber and a crosslinking system, said process comprising at least the following steps: incorporating the reinforcing filler into the diene elastomer, all at once or in several stages, and mixing; when the temperature of the mixture reaches a temperature of greater than 100° C., adding the crumb rubber; continuing the mixing up to a maximum temperature of between 120° C. and 190° C.; cooling the mixture to a temperature of less than 100° C.; incorporating the crosslinking system and mixing up to a maximum temperature of less than 110° C.

The invention relates to a process for devulcanizing a vulcanized rubber mixture, comprising the following steps: A) providing or producing a vulcanized rubber mixture, B) comminuting the vulcanized rubber mixture to a granular material composed of vulcanized rubber particles, where the vulcanized rubber particles have a maximum particle diameter of 100 mm, C) extruding the vulcanized rubber particles produced in step B) in a twin-screw extruder at a shear rate of less than 100 s.sup.−1, where the temperature of the vulcanized rubber particles during extrusion is less than 200° C., to give a devulcanized rubber mixture having a temperature above 100° C., D) cooling the devulcanized rubber mixture in a further kneading unit, so as to give a devulcanized rubber mixture having a temperature in the range from 50° C. to 100° C. The invention further relates to an apparatus for performing the process and to the use of the apparatus for devulcanization of a vulcanized rubber mixture.