Processable polyethylene/EPDM thermoplastic vulcanizates
US6667364B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 29, 2000 |
| Grant date | Dec 23, 2003 |
| Priority date | — |
| Expiry date | Feb 8, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08L23/0815
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
A blend of an EPDM made with VNB instead of ENB and specified melt viscosity reducers is imbued with a unique ability to form a processable blend with a polyolefin phase in which PE is present in a major amount by weight relative to PP. In the substantially fully cured vulcanizate (TPV) of the blend the ratio of PE to pEPDM is in the range from more than 1:3 up to about 1:0.6. This blend is made processable with less than 200 phr of a processing oil in presently available commercial processing equipment by using an inert melt viscosity reducer which is compatible with the pEPDM and PE phases without being substantially miscible in either. A preferred melt viscosity reducer is chosen from (a) a polyolefin selected from the group consisting of isotactic poly(1-butene), ethylene-co-1-butene, propene-co-1-butene and ethylene-co-propene-co-1-butene; (b) oils and waxes having a solubility parameter in the range from about 19.5 to 21.5; and (c) a block copolymer of a fatty acid and polyethylene oxide having a melting point lower than 150° C.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.