Process for producing foamed articles of aromatic polyesters
US4284596A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 8, 1980 |
| Grant date | Aug 18, 1981 |
| Priority date | — |
| Expiry date | Jan 8, 2000 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/05
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
This invention provides a commercially advantageous process for producing a foamed article of an aromatic polyester, especially a large-sized foamed article of aromatic polyester having a high expansion ratio. The process comprises mixing an aromatic polyester, a polyepoxy compound, a compound of a metal of Group Ia, IIa or IIIa of the periodic table and a blowing agent in a melt extrusion molding machine optionally with a fibrous filler while introducing the blowing agent thereinto under pressure, extruding the molten mixture from the molding machine, further expanding the foamed unsolidified extrudate in an atmosphere maintained at reduced pressure, and solidifying it by cooling in an atmosphere maintained at reduced pressure. The resulting aromatic polyester foamed article has numerous fine cells having uniform volumes, shapes and distribution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.