Block-copolymer-based stretchable, flexible, waterproof and breathable film
US12312444B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 16, 2018 |
| Grant date | May 27, 2025 |
| Priority date | — |
| Expiry date | Mar 15, 2039 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2379/08
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
The invention relates to a flexible, stretchable, waterproof breathable film based on a block copolymer comprising at least one rigid polyamide PA block and at least one flexible block, characterized in that said copolymer includes at least one carboxylic acid chain end blocked with a polycarbodiimide. The invention also relates to the use of a polycarbodiimide in a process for manufacturing a film based on a copolymer containing polyamide blocks and flexible blocks including at least one carboxylic acid chain end, for improving, simultaneously, the extrudability of the copolymer, the drawability of the copolymer in film form and/or for improving the extrusion rate of said copolymer, and for improving the stretchability of the film, the flexibility of the film, its abrasion resistance and its tear strength.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.