Elastomeric materials for components of tyres and tyres comprising modified silicate fibres

Patent metadata

Field	Value
Publication number	US-11383554-B2
Application number	US-201716343669-A
Country	US
Kind code	B2
Filing date	Oct 20, 2017
Priority date	Oct 26, 2016
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

The present invention relates to new vulcanisable elastomeric compositions for components of tyres, comprising modified silicate fibres as fillers. The silicate fibres are modified according to the process with controlled pH of the invention. In addition, the invention regards components of tyres, comprising elastomeric materials obtainable by vulcanisation of said compositions, and tyres for vehicles comprising one or more of said components. The vulcanised elastomeric materials according to the invention are characterised by good static and dynamic mechanical properties, in particular by particularly low hysteresis. Advantageously the tyres of the invention comprising one or more of said components have a limited rolling resistance.

First claim

The invention claimed is:

1. A process for modifying silicate fibres with needle-shaped morphology of nanometric size comprising:
providing silicate fibres with needle-shaped morphology of nanometric size comprising magnesium,
suspending the silicate fibres in a suitable liquid medium to generate a suspension,
adding, to the suspension, at least one acid compound, and bringing the medium to a pH ranging from 2 to 4,
maintaining the medium at the pH range from 2 to 4, by further adding the at least one acid compound, to extract from 10% to 70% by weight of magnesium from the silicate fibres to generate modified silicate fibres, wherein the modified silicate fibres are substantially preserved with a crystalline structure and needle-shaped morphology, and
separating the modified silicate fibres from the liquid medium, wherein the modified silicate fibres with needle-shaped morphology of nanometric size comprise 9.5% to 12% of magnesium.

2. The process as claimed in claim 1 , wherein the silicate fibres are sepiolite fibres.

3. The process as claimed in claim 1 , wherein the liquid medium is chosen from water, alcohols, ethers, ketones, and mixtures thereof.

4. The process as claimed in claim 1 , further comprising maintaining the medium at a pH range from 2.5 to 3.5.

5. The process as claimed in claim 1 , wherein adding the at least one acid compound to the medium results in a concentration of the at least one acid compound not higher than 0.01N.

6. The process as claimed in claim 1 , further comprising adding a silanising agent to the suspension.

7. The process as claimed in claim 6 , wherein the silanising agent is chosen from bis-(triethoxysilylpropyl)disulphide (TESPD), bis[3-(triethoxysilyl)propyl]tetrasulphide (TESPT), 3-thio-octanoyl-1-propyltriethoxysilane (NXT), Me 2 Si(OEt) 2 , Me 2 PhSiCl, and Ph 2 SiCl 2 .

8. The process as claimed in claim 1 , wherein extracting continues to not more than 65%, by weight of magnesium from the silicate fibres.

9. The process as claimed in claim 4 , further comprising maintaining the medium at a pH range from 2.8 to 3.2.

10. The process as claimed in claim 5 , wherein adding the at least one acid compound to the medium results in a concentration of the at least one acid compound not higher than 0.005N.

Assignees

• Pirelli

Inventors

• Giannini Luca
• Tadiello Luciano
• Hanel Thomas
• Cobani Elkid
• Di Credico Barbara
• D'Arienzo Massimiliano
• Scotti Roberto
• Morazzoni Franca
• Perez Cacho Jorge Jose
• Julve Sebastian Daniel Javier

Classifications

• C08K2201/016

  Additives defined by their aspect ratio · CPC title

• C08J2309/00

  Characterised by the use of homopolymers or copolymers of conjugated diene hydrocarbons · CPC title

• C04B14/042

  Magnesium silicates, e.g. talc, sepiolite · CPC title

• B60C2001/0033

  Compositions of the sidewall inserts, e.g. for runflat · CPC title

• B60C1/0016

  Compositions of the tread · CPC title