Reducing friction of EPDM and related rubbers
AssigneeCooper Technology Services, LLC
InventorHans-Joachim Graf
Life of this patent
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Abstract
A cured elastomeric rubber composition with a reduced coefficient of friction and a relatively high surface energy is disclosed. The composition comprises an elastomeric rubber with polar functional groups grafted to the polymer backbone. The polar functional groups can include amide, amine urethane, ester or silane functional groups. The elastomeric rubber may be any relatively non-polar elastomeric rubber such as EPDM or polyisoprene. Also incorporated into the rubber composition are various rubber additives including for example, carbon black, processing oils, curatives, and clay filler. The incorporation of various functional groups in the rubber compositions effectively reduces the coefficient of friction of the resulting cured rubber component.
Claims22
A polymeric rubber composition exhibiting a reduced coefficient of friction comprising:
- an elastomeric rubber polymer including a polymeric backbone and at least one functional group disposed along said polymeric backbone, said functional group selected from the group consisting of amide, amine, urethane, ester, silane, and combinations thereof;
- and
- a curing system in an amount sufficient to crosslink said elastomeric rubber polymer.
A low friction rubber composition comprising:
- an elastomeric polymer having disposed along its backbone one or more pendent groups selected from the group consisting of (i) maleic anhydride grafted polyethylene, wherein the maleic anhydride constitutes about 3.5% by weight of the maleic anhydride grafted polyethylene, (ii) butylamine grafted polyacrylate-maleic anhydride copolymer, (iii) hexadecylacrylamine, (iv) dodecylacrylamine, (v) cyclohexylamine octylamine, (vi) silane, and (vii) combinations thereof;
- wherein said pendent groups constitute about 1 to about 20% by weight of the grafted polymer;
- to 200 phr of a carbon black;
- to 150 phr of a processing oil;
- 0.5 to 5 phr of a sulfur source;
- and
- 1 to 12 phr sulfur cure accelerator.
A method for producing a low friction rubber composition, the method comprising the steps of:
- providing an elastomeric polymer;
- grafting one or more functional groups to said polymer to form a grafted polymer, said functional groups selected from the group consisting of (i) maleic anhydride grafted polyethylene, wherein the maleic anhydride constitutes about 3.5% by weight of the maleic anhydride grafted polyethylene, (ii) butylamine grafted polyacrylate-maleic anhydride copolymer, (iii) hexadecylacrylamine, (iv) dodecylacrylamine, (v) cyclohexylamine octylamine, (vi) silane, and (vii) combinations thereof;
- providing a cure system for said grafted polymer;
- mixing said grafted polymer with said cure system to form a rubber mixture;
- and
- curing said rubber mixture to form said low friction rubber composition.
Dependencies are inferred from the claim text.