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Indexed by:期刊论文

Date of Publication:2009-09-21

Journal:Materials Science Forum

Included Journals:EI、CPCI-S、Scopus

Volume:628 629

Page Number:429-434

ISSN No.:0878493123

Key Words:Polymer melts; Rheological characteristics; Micro scale effect

Abstract:The rheological characteristics of four polymer melts (PS, PMMA, PP and HDPE) are investigated by a capillary rheometer with the die diameters from 1.5mm to 0.5mm.The effects of temperature on shear viscosity and the effects of both temperature and shear rate on non-Newton exponent of melts are discussed when the die diameter is 0.5mm. The results show that the shear viscosity of four polymers decreases with the rise of shear rate. The shear viscosity of PS and PMMA increases with the decrease of die diameter, the shear viscosity of PP and HDPE decreases with die diameter and minute differences of shear viscosity with different die diameters are observed with the growth of shear rate. When the die diameter is 0.5mm, Arrhenius equation is found to be suitable to describe the relations between shear viscosity and temperature for four polymer melts. The non-Newton exponents of four polymer melts increase with the temperature and decrease with the rise of shear rate. © (2009) Trans Tech Publications, Switzerland.