A novel dynamic opto-thermo-mechanical stress testing device 2: In situ stretching process of polymeric fibers.

In this article, we used the opto-mechanical stress testing-device to stretch a monofilament of isotactic Polypropylene, iPP, fibers. This device was used to obtain the mechanical behavior of these fibers by measuring the complete stress-strain curves at different stretching conditions. Using this device, the different regions of iPP fiber where the mechanical deformation takes place was characterized, including the necking region and fracture initiation process. The obtained mechanical behavior of iPP fibers was correlated to the variations of different optical parameters by attaching the device with the Pluta polarizing interference microscope. This microscope and the stress device allowed us to simultaneously measure the optical parameters and stress-strain data during stretching process at different stretching speeds. These data provide us with comprehensive information on the opto-mechanical behavior of polymeric fibers. Interferograms are included for illustration. The opto-mechanical stress testing-device was used to stretch a monofilament of, iPP, fibers. The mechanical deformation takes place was characterized, including the necking region and fracture initiation process at different stretching speeds.