6533b85ffe1ef96bd12c287c
RESEARCH PRODUCT
No-flow temperature and solidification in injection molding simulation
G. HaaghG. A. MannellaValerio BrucatoW. ZoeteliefV. La Carrubbasubject
chemistry.chemical_classificationMaterials scienceinjection molding simulationMolding (process)Polymerlaw.inventionAmorphous solidPhysics::Fluid DynamicsCondensed Matter::Soft Condensed MatterViscosityTemperature dependence of liquid viscositychemistryRheologylawfilling stageCrystallizationComposite materialsolidificationGlass transitiondescription
The no‐flow temperature (NFT) is a parameter representing the rheological solidification temperature of a polymer. A polymer, during injection molding filling stage, can stop its flow because of its high viscosity, although it is not yet fully solidified by means of glass transition or crystallization. The NFT is used in most of injection molding simulation packages: with this simple parameter it is possible to reduce the errors deriving from viscosity extrapolation at relatively low temperatures. The viscosity measurements for polymers are usually carried out at high temperatures, and the viscosity models can fail in prediction at temperatures close to the glass transition or crystallization temperature.The NFT is still a parameter not well defined and a standard method to measure it is still lacking. Nevertheless, a simple correlation for NFT estimation, derived from Cross‐WLF equation, is proposed for both amorphous and semicrystalline polymers. The presented correlation takes into account the changes ...
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2011-01-01 |