Pendulum-type viscoelastic spectroscopy for relaxation modulus measurements

Abstract

The pendulum-type viscoelastic spectroscopy (PVS) is designed to measure linear viscoelastic properties of solid materials with a magnetic loading system and laser-based displacement measurement system The magnetic loading system consists of a permanent magnet and Helmholtz coils The displacement measurement system contains a solid state laser and silicon-based fourquadrant position sensor Current refinement enables PVS to measure relaxation function under constant deformation with a PID feedback control system The PID maintains the deformation of the sample while changing the electric current being sent into the Helmholtz coil A limitation of current relaxation experiment is the deformation must be small A LabView code is developed to systematically operate the PVS experiment including creep relaxation and dynamic loading In this work linear viscoelastic properties of polymer and rubbery materials such as PMMA and silicone rubber are experimentally measured The measured creep compliances and relaxation functions as well as loss tangent and complex modulus are examined by the theory of linear viscoelasticity

Date of Award	2014 Aug 27
Original language	English
Supervisor	Yun-Che Wang (Supervisor)