Microporous materials of ethylene-vinyl alcohol copolymer and methods for making same
US5962544A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 7, 1995 |
| Grant date | Oct 5, 1999 |
| Priority date | — |
| Expiry date | Dec 7, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31855
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A microporous shaped article is provided. The article comprises ethylene-vinyl alcohol copolymer which has an internal structure of a multiplicity of spaced, randomly dispersed, non-uniform shaped particles of ethylene-vinyl alcohol copolymer. Also provide is process for preparing microporous shaped articles comprising the steps of: (a) melt blending to form a mixture comprising ethylene-vinyl alcohol copolymer and a compatible polymer or compound in which the copolymer will dissolve to form a solution at the melting temperature of the copolymer, but will phase separate on cooling at or below the crystallization temperature of the ethylene-vinyl alcohol copolymer; (b) forming a shaped article of the melt blended mixture; (c) cooling the shaped article to a temperature to cause phase separation to occur between the compatible copolymer or compound and the ethylene-vinyl alcohol copolymer, thereby providing an article comprising an aggregate of a first phase comprising particles of ethylene-vinyl alcohol copolymer in a second phase comprising the compatible polymer or compound with adjacent ethylene-vinyl alcohol copolymer particles being distinct but having a plurality of zones of c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.