High strength extruded thermoplastic polymer foam
US9228070B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2011 |
| Grant date | Jan 5, 2016 |
| Priority date | — |
| Expiry date | Jun 14, 2032 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24504
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Prepare extruded thermoplastic polymer foam by preparing a foamable polymer mixture containing thermoplastic polymer and blowing agent at a mixing pressure, cooling the foamable polymer mixture and extruding it through a foaming die at a die pressure at least 90 bars lower than the mixing pressure and out through a die opening having cross sectional dimensions of 2.5 millimeter or more and a cross sectional area of at least 700 square millimeters at a flow rate greater than 500 kilograms per hour and allow it to expand into a polymer foam between shaping elements while restraining the extrusion rate with a restraining device so as to form polymer foam having 96 volume percent or less void volume, anisotropic cell size, a thickness of 50 millimeter or greater, compressive and tensile moduli in the thickness dimension greater than 35 mega pascals and an average shear modulus greater than 16 mega pascals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.