Porous air permeable polytetrafluoroethylene composites with improved mechanical and thermal properties
US11028245B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 30, 2017 |
| Grant date | Jun 8, 2021 |
| Priority date | — |
| Expiry date | Nov 30, 2037 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2479/08
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Porous air permeable expanded PTFE composite with enhanced mechanical and thermal properties are described. The node and fibril microstructure of expanded PTFE is coated on and within the node and fibril microstructure with a suitably chosen polymer to impart property enhancement while maintaining porosity. The coating polymer content of the composite is maintained between 3 and 25 weight percent of the composite and the areal mass of the composite is less than 75 gm/m2. Exemplary enhancement to properties may include, among others, Average Tensile Strength (ATS) (in MPa)×Z strength (in MPa) of 50 MPa2 or greater, preferably 100 MPa2 or greater, with air flow less than 500 Gurley seconds. Coating polymers with appropriate temperature resistance provides composites which further exhibit shrinkage of less than 10% at temperatures up to 300° C. with air flow of less than 500 Gurley seconds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.