Method of aging expansion-molded body of polyolefin
US4631159A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 1984 |
| Grant date | Dec 23, 1986 |
| Priority date | — |
| Expiry date | Nov 29, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S264/18
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method for aging an expansion-molded body of polyolefin prepared by heating pre-expanded polyolefin particles within a mold involves cooling the molded body within the mold so that the molded body is not substantially smaller than the volume of the mold cavity and is temporarily expandable after being removed from the mold to not more than 110% relative to the volume in the mold cavity, removing the molded body from the mold, placing the molded body in an atmosphere substantially under atmospheric pressure and having a temperature of 25.degree. to 55.degree. C. lower than the melting point of the polyolefin while the volume of the molded body is 70 to 110% relative to the volume of the mold cavity and holding the molded body in this atmosphere until the temperature of the molded body is at least equal to the temperature of the atmosphere.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.