Related Experiment Video
Updated: Dec 30, 2025

Magnet Assisted Composite Manufacturing: A Flexible New Technique for Achieving High Consolidation Pressure in Vacuum Bag/Lay-Up Processes
Published on: May 17, 2018
Effect of Free-Volume Hole Fraction on Dynamic Mechanical Properties of Epoxy Resins Investigated by
H J Zhang1, S Sellaiyan1, K Sako1
1Division of Applied Physics, Faculty of Pure and Applied Science, University of Tsukuba, Tsukuba, Ibaraki 305-8573, Japan.
Abstract:
Dynamic mechanical analysis experiments were carried out to investigate the mechanical properties of four types of chemically different epoxy resins. Pressure-volume-temperature (PVT) experiments were performed to determine the free-volume hole fraction (hPVT) of each epoxy resin using the Simha-Somcynsky lattice-hole theory. Using the Williams-Landel-Ferry equation, the correlations between the relative hole fraction (1 - hPVT/hPVT, where hPVT is the hole fraction at a reference temperature Tr) and four typical parameters reflecting dynamic mechanical properties [storage modulus (E'), loss modulus (E″), damping factor (tanδ), and complex viscosity (|η*|)] were studied in the temperature range from Tg(PVT) (the glass transition temperature determined by PVT data) to Tg(PVT) + 100 °C. In the temperature range from Tg( (temperature corresponding to the intersection of the two tangent fitting lines in the E'(T) curve indicating the glassy-state and glass-transition stages) to Tg(PVT) + 100 °C, the variations in the four dynamic mechanical parameters with a relative hole fraction could be separated into two distinct categories: (i) log[E'(T)] and log[|η*|(T)] decreased linearly to their minimum values and then remained nearly unchanged with increasing relative hole fraction, and (ii) log[E″(T)] and log[tanδ(T)] first increased monotonically to their maximum values and then decreased linearly with the increasing relative hole fraction. This study demonstrates that the PVT technique is a feasible and reliable experimental method to determine the hole fractions of thermoset polymers.
Related Concept Videos
Dynamic Modulus of Elasticity of Concrete
The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x 4 x 20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by a...
Le Chatelier's Principle: Changing Volume (Pressure)
Pressure Variation in a Fluid at Rest
When measuring pressure at two different levels within the fluid, the difference in...
Real Gases: Effects of Intermolecular Forces and Molecular Volume Deriving Van der Waals Equation
pV-Diagrams
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity

