Fracture behavior characterization of arcan polycaprolactone based polymer composites prepared by polymerization induced phases separation

Polycaprolactone (PCL) based polymer composites have several potential engineering applications. This study investigated the fracture toughness of polycaprolactone based polymer composites under mode I, mode II, and mixed mode I&II, according to the use of Arcan composite specimens. The specimen was prepared through a polymerization‐induced phase separation (PIPS) process by diffusing polycaprolactone within an epoxy matrix. The thermal properties and morphology of the specimen fracture surfaces were characterized firstly. After that shape memory performance of the prepared specimen was preliminarily studied by measuring the recovered strain and stress. Specimens were tested under compression according to ASTM D6641. Arcan specimens used in this study for studying the fracture behavior under different fracture modes were prepared using a Waterject. The effect of loading angles on the fracture behavior was investigated as well. The results show that Arcan specimen has advantages on studying the fracture behavior of polycaprolactone based polymer composite under different fracture modes. It found that the average size decreases as the amount of PCL increasing. The globules are uniformly distributed across the fracture surfaces. The shape memory test shows that the larger programmed strain the larger recovered stress. In addition, the increase of PCL amount leads to the decrease of composite K_IC but the increase of K_IIC (i.e., improved shear resistance). We envision application of the developed Arcan test fixture as a testing device to exam the crack healing efficiency under different fracture modes. POLYM. COMPOS., 40:1198–1208, 2019. © 2018 Society of Plastics Engineers