Thermosetting materials, such as epoxy, have been widely applied in many areas including automotive, aerospace and electronics industries in the form of surface coating, structural adhesives, advanced composites and packaging materials. These kind of materials pose high mechanical strength, high temperature stability and good solvent resistance. Unlike thermoplastic polymers, the process of thermosets involves an irreversible chemical crosslinking reaction. The performance of the final products is heavily dependent on the experimental conditions such as chemical composition, cure temperature, and cure time. Many analytical techniques including differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), rheology, dynamic mechanical analysis (DMA), and dielectric analysis (DEA), have been used for the study of curing process. In this presentation, we elaborate in detail on how to use thermal, rheological and mechanical techniques to study thermoset materials. We will discuss how to design good test methods to monitor curing, and quantitatively calculate kinetics and activation energy. Dynamic mechanical analysis is the most common technique that is used to evaluate the mechanical performance of the end use product. It is capable of quantitatively measuring the difference of thermosets with different process conditions, crosslinking density and composite filler content. We will also provide applications examples to demonstrate how DMA can be used to quantitatively measure the glass transition, modulus and elasticity of thermosets.
About the Speaker
Tianhong (Terri) Chen, Ph.D. is a Senior Applications Support Scientist with TA Instruments currently supporting the Rheology and DMA product lines. She received her PhD degree in Polymer Science from Sun Yat-sen University (SYSU) in China, specializing in polymer synthesis and characterization. She did her post-doc research and later became a research assistant professor at the University of Maryland. During that time, her research was focused on biopolymer modifications and analysis. Dr. Chen joined TA Instruments in 2004. Her key responsibilities at TA Instruments are customer support, consultation, and teaching DMA and rheology training courses. Dr. Chen has more than 50 publications in peer-reviewed journals and two US patents.