Production of nanofibers by electrospinning for interfacial toughening of composites

Özçınar, Zeynep Cansu
In this work, electrospinning technique was selected for the production of nanofiber mats to be used in improving the fracture toughness of carbon fiber reinforced composites. The main purpose of this study is to improve GIC delamination mode of polyamide-6 (PA6) nanofibers interleaved carbon fiber reinforced polymer (CFRP) composite. Many studies [1]-[4] have shown that when PA6 nanofiber is used as an interleaving material for improving delamination modes of composites GIIC sliding mode could be significantly increased. However, GIC opening mode could not be improved or even worsened. In an attempt to solve this problem, nanofibers were produced with different combinations and mass ratios of Polyamide 6 (PA6), poly (trimethylene carbonate) (PTMC), poly (Ɛ-caprolactone) (PCL) and shellac polymers. These nanofibers were used as an interleaving material for carbon fiber reinforced polymer (CFRP) composites. GIC fracture toughness of produced composite laminates were tested by means of Double Cantilever Beam (DCB) test. After this test, fracture surfaces of composites were analyzed with the help of Scanning Electron Microscopy (SEM). Among the all results obtained during this study, 13% enhancement in GIC initiation stage compared to neat composite laminate were obtained with combination of PA6 nanofiber and shellac beads interleaving mat.


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In order to fulfill growing demand for lighter aircraft, Carbon fiber reinforced polymers (CFRP) have been developed, which differ from metals with regards to their machinability characteristics. The main problem in machining process is the damage caused by delamination of CFRP materials which need to be both cut and shorn of fibers at the same time, since they are remarkably abrasive in nature. This research aims at accessing the most appropriate cutting condition with less tool wear in routing and trimmin...
Citation Formats
Z. C. Özçınar, “Production of nanofibers by electrospinning for interfacial toughening of composites,” Thesis (M.S.) -- Graduate School of Natural and Applied Sciences. Chemical Engineering., Middle East Technical University, 2019.