Soft ethylenic polymer blend foams
US4215202A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 22, 1979 |
| Grant date | Jul 29, 1980 |
| Priority date | — |
| Expiry date | Feb 22, 1999 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S521/91
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Low density, closed cell, soft foam products having dimensional stability are made from ethylenic resin blends having low stiffness by extrusion foaming, wherein the heat plastified gel comprises the ethylene polymer blend and at least one volatile blowing agent. The blends especially comprise a copolymer of ethylene and monoethylenically unsaturated carboxylic acid and a copolymer of ethylene and at least one monoethylenically unsaturated non-ionic comonomer. The starting ethylenic resin blends are preferably blends of ethylene acrylic acid copolymers and ethylene vinyl acetate copolymers, having stiffness less than about 20,000 psi. Exemplary volatile blowing agents are 1,2-dichlorotetrafluoroethane, 1-chloro-1,2,2,2-tetrafluoroethane and 2,2-difluoropropane.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.