6533b7d7fe1ef96bd1268331
RESEARCH PRODUCT
Shear and nonisothermal elongational characterization of a liquid crystalline polymer
Antonino ValenzaF. P. La Mantiasubject
chemistry.chemical_classificationTerephthalic acidMaterials sciencePolymers and PlasticsLiquid crystallineGeneral ChemistryPolymerDie swellPlasticitychemistry.chemical_compoundShear (geology)chemistryMaterials ChemistryExtrusionComposite materialdescription
A commercial liquid crystalline polymer (LCP) sample was characterized both in shear and in nonisothermal elongational flow over a wide range of temperatures (240–350°C). The LCP sample employed was a copolyesteramide of 2,6 hydroxynaphthoic acid, terephthalic acid, and aminophenol manufactured by Celanese and commercially known as Vectra B950. The viscosity decreases dramatically at temperatures above the crystal-nematic transition of the polymer. At lower temperatures, the extrusion of the sample is mainly due to plastic flow. Die-swell values are very small and contraction of the extrudate is also revealed, but the sample shows high elasticity. The polymer is not spinnable at very low temperatures, and the melt strength rapidly decreases with increasing temperature.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1989-05-01 | Polymer Engineering and Science |