Tyre for vehicle wheels

Patent metadata

Field	Value
Publication number	US-11208542-B2
Application number	US-201716467190-A
Country	US
Kind code	B2
Filing date	Dec 12, 2017
Priority date	Dec 13, 2016
Publication date	Dec 28, 2021
Grant date	Dec 28, 2021

Abstract

The present invention relates to a tyre for vehicle wheels comprising at least one structural element comprising a cross-linked elastomeric material obtained by cross-linking a cross-linkable elastomeric composition comprising carbon nanotubes, wherein said carbon nanotubes are obtained with an iron oxides and/or aluminium oxides based catalyst substantially free of Co, Ni and Mo.

First claim

The invention claimed is:

1. A process for producing iron oxide and/or aluminium oxide catalysts substantially free of Co, Ni, and Mo comprising:
preparing an aqueous solution (i) comprising a Fe 3+ soluble salt and an Al 3+ soluble salt, wherein the solution (i) comprises a molar concentration of Fe 3+ ranging from 0.3 to 1.5 M and a molar concentration of Al 3+ ranging from 0.8 to 2.4 M,
preparing an aqueous solution (ii) comprising ammonium hydroxide, wherein the solution (ii) comprises a molar concentration of NH 3 ranging from 1.8 to 18 M,
adding solution (ii) to solution (i), wherein an amount of NH 3 added per minute ranges from 1.3·10 −4 to 4.5·10 −1 moles per total moles of iron or aluminium or both iron and aluminium, resulting in a combined solution with a pH ranging from 6 to 8, wherein a gel of the combined solution forms,
drying the gel at a temperature ranging from 35° C. to 100° C. to obtain a solid, and
calcining the obtained solid at a temperature ranging from 250° C. to 750° C. under an atmosphere chosen from air and nitrogen.

2. The process according to claim 1 , wherein the Fe 3+ molar concentration ranges from 0.5 to 1.1 M.

3. The process according to claim 1 , wherein the Al 3+ molar concentration ranges from 1.2 to 1.8 M.

4. The process according to claim 1 , wherein the NH 3 molar concentration ranges from 10 to 18 M.

5. The process according to claim 1 , wherein the amount of NH 3 added per minute during the addition of solution (ii) to solution (i) ranges from 2.5·10 −4 to 2·10 −1 moles per total moles of iron and aluminium.

Assignees

• Pirelli
• Milano Politecnico

Inventors

• Mazzocchia Carlo Vittorio
• Daghetta Matteo Antonio
• Pellegrino Lorenzo
• Citterio Attillio
• Albizzati Enrico
• Giannini Luca
• Hanel Thomas

Classifications

• B01J23/745 Primary

  Iron · CPC title

• C08L9/00 Primary

  Compositions of homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• C08L7/00 Primary

  Compositions of natural rubber · CPC title

• C08K3/041

  Carbon nanotubes · CPC title

• C01B32/162

  characterised by catalysts · CPC title