Irradiated multilayer film having seal layer containing hyperbranched polymer
US6761965B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 2002 |
| Grant date | Jul 13, 2004 |
| Priority date | — |
| Expiry date | Mar 25, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31938
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An irradiated multilayer film has a first layer and a second layer. The first layer is an outer heat seal layer containing a blend of a highly branched homogeneous polymer and a semicrystalline polymer. The highly branched homogeneous polymer has at least 40 branches per 1000 methylene groups, an Mw/Mn less than 3.0, and a density of less than 0.89 g/cc. The highly branched homogeneous polymer is present in an amount of from about 5 to 50 weight percent, based on layer weight. The semicrystalline polyolefin has a density of at least 0.90 g/cc. The semicrystalline polyolefin is present in an amount of from about 50 to 95 weight percent, based on total layer weight. The second layer contains a thermoplastic polymer in a crosslinked polymer network. A process for making a packaging article includes coextruding the first and second layers, irradiating the resulting multilayer film, and thereafter heat sealing the first layer to itself or another component of the packaging article.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.