Method of making microporous material
US7445735B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 7, 2004 |
| Grant date | Nov 4, 2008 |
| Priority date | — |
| Expiry date | Dec 20, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/249986
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A method for producing a microporous material comprising the steps of: providing an ultrahigh molecular weight polyethylene (UHMWPE); providing a filler; providing a processing plasticizer; adding the filler to the UHMWPE in a mixture being in the range of from about 1:9 to about 15:1 filler to UHMWPE by weight; adding the processing plasticizer to the mixture; extruding the mixture to form a sheet from the mixture; calendering the sheet; extracting the processing plasticizer from the sheet to produce a matrix comprising UHMWPE and the filler distributed throughout the matrix; stretching the microporous material in at least one direction to a stretch ratio of at least about 1.5 to produce a stretched microporous matrix; and subsequently calendering the stretched microporous matrix to produce a microporous material which exhibits improved physical and dimensional stability properties over the stretched microporous matrix.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.