Expanded foamed bead of a rubber-modified styrene polymer
US5635543A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 11, 1996 |
| Grant date | Jun 3, 1997 |
| Priority date | — |
| Expiry date | Jun 11, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S525/901
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
Disclosed is an expanded foamed bead of a rubber-modified styrene polymer, comprising a plurality of closed cells defined by cell walls which constitute a matrix for the bead, wherein each of the cell walls comprises two surfaces separated by a distance equal to the thickness of the cell wall. The matrix comprises: (a) a continuous styrene polymer phase; and (b) a rubber phase dispersed in said continuous styrene polymer phase (a), wherein the rubber phase comprises a plurality of substantially flat, butadiene polymer rubber particles each having at least one styrene polymer particle occluded therein; wherein the flat rubber particles are arranged in lamellar configuration along the thickness of the cell wall and are oriented so that the long axis of a cross-section of each flat rubber particle, as viewed in a cross-section of the cell wall, taken along the thickness of the cell wall, is substantially parallel to the two surfaces of the cell wall, and wherein the cell wall and each flat rubber particle satisfy specific dimensional relationships. The expanded foamed bead of the present invention is not only excellent in its ability to retain a foaming agent gas within the closed cel…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.