Method and apparatus for microcellular polymer extrusion
US6284810A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 26, 1999 |
| Grant date | Sep 4, 2001 |
| Priority date | — |
| Expiry date | Feb 26, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2105/16
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Continuous polymeric extrusion nucleation systems and methods useful for making polymeric microcellular foamed materials, including crystalline and semi-crystalline polymeric microcellular materials, are provided. Pressure drop rate is an important feature in some embodiments, and the invention provides systems for controlling these and other parameters. One aspect involves a multiple-pathway nucleator that is separated from a shaping die by a residence chamber. Another aspect involves a die for making advantageously thick articles, including a multiple-pathway nucleation section. Microcellular material can be continuously extruded onto wire, resulting in a very thin, essentially closed-cell microcellular insulating coating secured to a wire. Other very thin microcellular products can be fabricated as well.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.