Processes for forming vulcanizable elastomeric formulations and vulcanized elastomeric articles

Patent metadata

Field	Value
Publication number	US-10280281-B2
Application number	US-201715659094-A
Country	US
Kind code	B2
Filing date	Jul 25, 2017
Priority date	Feb 4, 2016
Publication date	May 7, 2019
Grant date	May 7, 2019

Abstract

Processes for forming a vulcanizable elastomeric formulation are disclosed. The processes include the steps of mixing an elastomer with a vulcanizing agent to form a vulcanizable elastomeric formulation that includes the vulcanizing agent dispersed in the elastomeric compound, wherein the vulcanizing agent includes a cyclododecasulfur compound. A process for forming a vulcanized elastomeric article is also described.

First claim

The invention claimed is:

1. A process for forming a vulcanizable elastomeric formulation, said process comprising mixing an elastomer with a vulcanizing agent to form a vulcanizable elastomeric formulation that includes said vulcanizing agent dispersed in the elastomeric compound; wherein said vulcanizing agent includes a cyclododecasulfur compound.

2. The process of claim 1 wherein said cyclododecasulfur compound is characterized by a DSC melt point onset of from about 155° C. to about 167° C. when measured at a DSC heat rate of 20° C./minute.

3. The process of claim 2 wherein said cyclododecasulfur compound is characterized by a DSC melt point onset of between 157° C. to about 167° C. when measured at a DSC heat rate of 20° C./minute.

4. The process of claim 1 wherein said mixing step comprises combining a vulcanizing composition with said elastomer to form said vulcanizable elastomeric formulation, wherein said vulcanizing composition comprises said cyclododecasulfur compound.

5. A process for forming an elastomeric article, said process comprising a) mixing an elastomer with a vulcanizing agent to form a vulcanizable elastomeric formulation that comprises said vulcanizing agent dispersed in said elastomer, wherein the vulcanizing agent includes a cyclododecasulfur compound; b) forming the vulcanizable elastomeric formulation into a formed shape; and c) vulcanizing the formed shape to form a vulcanized elastomeric article.

6. The process of claim 5 wherein at least one of said mixing and forming steps comprises increasing the bulk average processing temperature of said vulcanizable elastomeric formulation to greater than 125° C. for at least a portion of said step.

7. The process of claim 5 wherein at least one of said mixing and forming steps comprises increasing the bulk average processing temperature of said vulcanizable elastomeric formulation to greater than 128° C. for at least a portion of said step.

8. The process of claim 5 wherein at least one of said mixing and forming steps comprises increasing the bulk average processing temperature of said vulcanizabie elastomeric formulation to greater than 130° C. for at least a portion of said step.

9. The process of claim 5 wherein at least one of said mixing and forming steps comprises increasing the bulk average processing temperature of said vulcanizable elastomeric formulation to greater than 135° C. for at least a portion of said step.

10. The process of claim 1 wherein said vulcanizable elastomeric formulation further comprises at least one of an antireversion agent, a prevulcanization inhibitor and retarder.

11. The process of claim 10 wherein said vulcanizing composition further comprises an antireversion agent.

12. The process of claim 11 wherein said antireversion agent is selected from the group consisting of hexamethylene-1,6-bis(thiosulfate), disodium salt, dihydrate and 1,3-bis(citraconamidomethyl)benzene.

13. The process of claim 10 wherein said vulcanizable elastomeric formulation composition further comprises a prevulcanization inhibitor.

14. The process of claim 13 wherein said prevulcanization inhibitor is N-(cyclohexylthio) phthalimide.

15. The process of claim 1 wherein said vulcanizable eiastomeric formulation further comprises at least one crosslinker selected from the group consisting of polysulfides, polysulfide mixtures and crosslinked organosilicon polysulfides.

16. The process of claim 1 wherein said vulcanizable elastomeric formulation further comprises at least one accelerator selected from the group consisting of 2-mercaptobenzothiazole, 2-mercaptobenzothiazole disulfide and asymmetric disulfides based on 2-mercaptobenzothiazole and a non-accelerating mercapto containing moiety.

Assignees

• Eastman Chem Co

Inventors

• Barnicki Scott Donald
• Ignatz-Hoover Frederick
• Hembre Robert Thomas
• Smith Andrew Neil
• Kreulen Henk
• Velamakanni Aruna M

Classifications

• C01B17/02 Primary

  Preparation of sulfur; Purification · CPC title

• C08J2307/00

  Characterised by the use of natural rubber · CPC title

• C08K3/30 Primary

  Sulfur-, selenium- or tellurium-containing compounds · CPC title

• C01B17/06

  from non-gaseous sulfides or materials containing such sulfides, e.g. ores · CPC title

• C08K3/06

  Sulfur · CPC title