Dry ice assisted polymer processing, methods for making, and articles formed thereof
US9458296B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 4, 2012 |
| Grant date | Oct 4, 2016 |
| Priority date | — |
| Expiry date | Mar 31, 2035 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C48/395
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
In an embodiment, a method of processing a polymer comprises: mixing polymer and solid carbon dioxide; introducing the polymer and solid carbon dioxide mixture to a hopper of a vented extruder; plasticizing the mixture to form a polymer melt with dissolved carbon dioxide; venting carbon dioxide as a gas before the die exit; and extruding the polymer melt through a die. In an embodiment, a method of making an article comprises: introducing a polymer powder to an extruder; introducing solid carbon dioxide powder to the extruder at the hopper; plasticizing and extruding the polymer and solid carbon dioxide mixture; venting the solid carbon dioxide before the die exit; extruding the polymer melt through a die to form pellets; and injection molding the polymer pellets without solid carbon dioxide to form molded articles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.