Natural rubber

Patent metadata

Field	Value
Publication number	US-11345795-B2
Application number	US-201816652617-A
Country	US
Kind code	B2
Filing date	Nov 15, 2018
Priority date	Nov 23, 2017
Publication date	May 31, 2022
Grant date	May 31, 2022

Abstract

A cup lump natural rubber devoid of impurities with a size of greater than 0.5 mm and having a plasticity retention index of greater than 80 is provided. The use of such a natural rubber in a line for manufacturing a semi-finished product based on natural rubber makes it possible to ensure an improved compromise of performances which are the productivity of a line for manufacturing semi-finished products and the quality of the semi-finished products resulting from this production line.

First claim

The invention claimed is:

1. A cup lump natural rubber, the cup lump natural rubber being devoid of impurities with a size of greater than 0.5 mm, and the cup lump natural rubber having a plasticity retention index of greater than 80.

2. The cup lump natural rubber according to claim 1 having a plasticity retention index of greater than or equal to 85.

3. The cup lump natural rubber according to claim 1 having a weight content of impurities of less than 0.12%.

4. The cup lump natural rubber according to claim 1 having a weight content of impurities of less than 0.05%.

5. The cup lump natural rubber according to claim 1 , wherein the cup lump natural rubber has a water content of less than 0.8% by weight.

6. The cup lump natural rubber according to claim 1 having a weight content of nitrogen of less than 0.4%.

7. The cup lump natural rubber according to claim 1 having a weight content of nitrogen of less than or equal to 0.3%.

8. The cup lump natural rubber according to claim 1 , wherein the cup lump natural rubber is devoid of impurities with a size of greater than 0.1 mm.

9. The cup lump natural rubber according to claim 1 , wherein the cup lump natural rubber is a stabilized natural rubber.

10. The cup lump natural rubber according to claim 9 , wherein the cup lump natural rubber is a natural rubber stabilized by a viscosity stabilizer selected from the group consisting of the compounds of formula XNH 2 and the salts of the compounds of formula XNH 2 , X representing a hydroxyl group or a C 1 -C 4 hydroxyalkyl group.

11. The cup lump natural rubber according to claim 10 , in which the viscosity stabilizer is hydroxylamine sulfate or hydroxylamine sulfate neutralized with sodium hydroxide.

12. The cup lump natural rubber according to claim 1 , wherein the cup lump natural rubber has a weight-average molar mass of greater than 1,000,000 g/mol.

13. A rubber composition comprising the natural rubber defined in claim 1 .

14. The rubber composition according to claim 13 , further comprising a reinforcing filler.

15. A semi-finished product comprising the rubber composition defined in claim 14 .

16. A tire comprising the rubber composition defined in claim 14 .

17. The cup lump natural rubber according to claim 11 , wherein the viscosity stabilizer is hydroxylamine sulfate.

18. A tire comprising the semi-finished product defined in claim 15 .

Assignees

• Michelin & Cie

Inventors

• GRANET Françoise
• Bernard Denis
• Dussillols Jérôme

Classifications

• C08C3/02 Primary

  Purification · CPC title

• C08L7/00

  Compositions of natural rubber · CPC title

• C08K3/36

  Silica · CPC title

• B60C1/00

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title

• C08K5/41 Primary

  Compounds containing sulfur bound to oxygen · CPC title