Melt rheometer for the measurement of flow properties of foamable plastics and polymer compositions
US4137754A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 8, 1977 |
| Grant date | Feb 6, 1979 |
| Priority date | — |
| Expiry date | Dec 8, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N11/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for the determination of the flow properties of thermoplastic materials in admixture with volatile liquids or other additives comprising an extruder which is employed to melt the polymer and admix therewith volatile blowing agents or additives. Subsequently the molten mixture is injected into an extrusion plastometer or rheometer for extruding the mixture, while still in molten form, through a capillary orifice in the extrusion plastometer. When volatile liquid blowing agents are admixed with the molten polymer in the extruder, an adjustable linkage is provided interconnecting the plastometer and the extruder whereby the pumping rate of the blowing agent can be variably adjusted and the blowing agent positively injected into the molten polymer within the extruder by the reciprocal motion of a piston means employed in the extrusion plastometer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.