Thermooxidative stabilization of polyolefins with an oxo-piperazinyl-triazine and a phosphorous acid ester
US5278209A · kind A · utility
Inventors
Key dates
| Filing date | May 26, 1992 |
| Grant date | Jan 11, 1994 |
| Priority date | — |
| Expiry date | May 26, 2012 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08K5/527
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Only two symmetrical stabilizers in a polyolefin or copolymer thereof, provide thermooxidative ("TO") or antioxidative ("AO") stability. One is an arylphosphite or arylfluorophosphite; the other is a monomolecular tri-substituted triazine in which each of three chlorine atoms on a trihalo-s-triazine is substituted with a piperazinone in which the N atom in the 4-position is alkylated. Only a trace amount of phosphite, at least 0.01 phr but less than 0.1 phr, is used so that the ratio of the piperazinone-substituted stabilizer to ester is greater than 1; additional phosphite has no noticeable effect. The trace amount of phosphite has a surprising booster effect, giving the stabilized composition excellent TO stability. Articles thermoformed from the stabilized polyolefin or copolymer thereof may be used under the hood or the dash of a vehicle, and, in containers for packaging goods, all of which articles are subject to TO degradation even if they are not subject to ultraviolet light degradation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.