Thermodegradable compositions based on crystalline homo- or copolymers of propylene and process for carrying out the selective degradation of such homo- and copolymers
US4948820A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 27, 1989 |
| Grant date | Aug 14, 1990 |
| Priority date | — |
| Expiry date | Jan 27, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S525/938
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Selective thermodegradation of homo- and copolymers of propylene, without encountering thermo-oxidation phenomena, by treating the polymer at 250.degree.-350.degree. C. in the presence of primary and/or secondary antioxidant and of a derivative of benzopinacol having formula (I): ##STR1## wherein n=1, or=0, and when n=1, X may be=1, and in this case Z.sub.1 and Z.sub.2 form together with each other ##STR2## groups, ##STR3## wherein R.sub.1, R.sub.2, R.sub.3, which may be the same or different, are alkyl or aryl radicals; PA0 or X ranges from 3 to 20 and in this case Z.sub.1 and Z.sub.2 are aryl radicals, A and B are R.sub.1 -Si-R.sub.2 groups that are part of an oligomer having formula: ##STR4## and when n=0, X is=1, Z.sub.1 and Z.sub.2 are aryl radicals, and ##STR5##
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.