Thixotropy-loop tests by using upper convected differential Maxwell-type model with kinetic theory

Abstract

The thixotropy-loop tests of a LDPE (PE-FSB-23D022/Q200) melt were described in the present paper by using the simplified Acierno-type constitutive equation, which was formed by a modified upper convected Maxwell model and a kinetic equation. The simplified Acierno model is a single-mode equation and only contains three parameters. The descriptions of the simplified Acierno model show partial agreements with the triangular-form thixotropy loop tests of the LDPE melt, in which the calculations of the model show agreement with the tests experiencing short- and medium-time shearing, but show some deviation with the experiment experiencing long-time shearing. The simplified Acierno model can reflect some typical viscoelastic properties of the melt.

Keywords

thixotropy-loop tests / LDPE melt / simplified Acierno-type equation