Bridgestone Corporation

Bridgestone Europe Nv/sa

Alessandra Bartoloni

Raffaele Di Ronza

Pasquale Agoretti

Giancarlo Cossu

Francesco Botti

John Nazareno House

Alessandra Calzetta

Michele Amurri

Andrea Sabella

Enrico Fresch

A process for the manufacture of a tread band for pneumatic tyres, wherein the blocks thereof comprise different rubber portions characterized by a different hysteresis loss. The process comprises a shredding step, wherein from a first and from a second rubber tread compound a plurality of fragments is manufactured with dimensions of between 6 and 30 mesh; a mixing step, wherein the fragments from the first and second compound are mixed together in order to obtain a mixture wherein the fragments are distributed in a random manner and retain their chemical/physical individuality; and an extrusion step, wherein the mixture from the preceding step is extruded for the manufacture of the tread band. The first and second compounds have different dynamic properties in terms of: dynamic modulus at 30° C., tanδ at 0° C., tanδ at 30° C. and tanδ at 60° C. The fragments retain a chemical/physical individuality both within the mixture formed during the mixing step and within the tread band formed during the extrusion step.

Process for the manufacture of a multi-compound tread for pneumatic tires for road vehicles

A rubber compound for pneumatic tyres comprising a cross-linkable unsaturated-chain polymer base, carbon black, a silane bonding agent and a vulcanization system. Part of the carbon black is carbon black from pyrolysis having a surface functionalization deriving from a treatment with an aminoacidic compound comprising at least one thiol group or a disulfide group.

Rubber compounds for pneumatic tyres comprising recycled carbon black

A rubber compound comprising at least one polymer base with cross-linkable unsaturated chain, a reinforcing filler, a vulcanization system and an interaction agent between the polymer base and the reinforcing filler consisting of a compound having an amine group and a sulphur atom adapted to react with the polymer base in the vulcanization step. The interaction agent has formula (II) or (III); wherein: wherein:

Rubber compound to produce tyres

A method of producing a rubber compound containing silica, the method including a step of dispersing the silica in a polymer base, and a following step of mixing the previously formed mixture with curing agents. The step of dispersing the silica in the polymer base includes the following sequence of operations: soaking the polymer base in a liquid silica precursor to form a swollen polymer; &#x2014;adding the swollen polymer to an organic solvent, and continually stirring the swollen polymer solution; &#x2014;adding water and a silica synthesizing catalyst to the swollen polymer solution; &#x2014;precipitating a polymer gel matrix by adding a precipitating agent; &#x2014;separating and washing the precipitated polymer gel matrix.

Method of producing a rubber compound comprising silica

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Rome, Italy

Alessandra Bartoloni