The Effect of Nano Fillers on the Polymerization Shrinkage Kinetics and Mechanical Behavior of Composites

Document Type

Contribution to Book

Publication Date


Publication Title

Proceedings of Behavior and Mechanics of Multifunctional Materials and Composites




The main objective of the present study was to investigate the effect of nanoclay reinforcement on time-dependent volumetric shrinkage of three epoxy resins during polymerization and associated change of mechanical properties of the resulting composite materials. The materials used in this work were two part epoxies from Applied Poleramics Inc., namely, ER3/EH103, ER10/EH103, and DR5/EH103. Conventional methods which utilize 1D and 2D strains measurement are highly dependent on boundary conditions and can be used only for approximation of volumetric measurements. In order to measure the volume directly and monitor time-dependent shrinkage during the polymerization process, the Accupyc II 1340 gas pycnometer with Peltier controller was used. The materials were cured in-situ in the pycnometer chamber at 49 °C for 4 h followed by a post cure of 4 h at 65 °C. Time-dependent shrinkage of individual resins was monitored through continuous volumetric measurements during the entire curing cycle. On the other hand, the tensile specimens were cured in the conventional oven using the same curing cycle. Experimental results showed that depending on the epoxy and nanoclay concentration, variation in time-dependent shrinkage was observed relative to pristine epoxies. Besides, inclusion of nanoclay has shown considerable change in mechanical properties of the composite material. Although such observations were expected, detailed quantification on the volumetric shrinkage with a new technique and its effect on structural components made of such resin are not well documented. Overall, the study lays the groundwork for understanding shrinkage induced effects on strengths of resin/adhesive dominant structural components.