Process for improving ozone and flex resistance of certain elastomers
US4090989A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 21, 1976 |
| Grant date | May 23, 1978 |
| Priority date | — |
| Expiry date | Jun 21, 1996 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K5/005
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
Ozone resistance of vulcanized chloroprene homopolymers and copolymers, chlorinated isobutylene/isoprene copolymers, and blends of any of the above with up to equal weight of styrene/butadiene copolymer or natural rubber is improved by incorporating into the polymer or polymer blend prior to vulcanization about 0.5-5 parts per 100 parts by weight of polymer or polymer blend of one or more of bis(5-norbornene-2-methyl) phosphite, tris(5-norbornene-2-methyl) phosphite, and tris(5-norbornene-2-methyl) phosphate. These esters also improve the flex resistance of chloroprene copolymers with sulfur and their blends with styrene-butadiene copolymers or natural rubber. In addition to improving ozone and flex resistance of the above polymers and polymer blends, these esters do not cause staining or discoloration of the vulcanized polymers.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.