Characterization of the shape memory effect in printing/writing transparency, eFlex TPU & eLastic TPE filament

• Main Author: Adzizul Fadleigh Ramli
• Other Authors: Huang Weimin
• Format: Final Year Project
• Language: English
• Published: 2018
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/75794
• Institution: Nanyang Technological University

This report aims to investigate the capabilities of 4 materials and their abilities in exhibiting the shape memory effects, namely printing and writing transparencies, and two 3D printing filaments which are Thermoplastic Elastomer (TPE) and Thermoplastic polyurethane (TPU). These materials were chosen as they represent relatively common forms of plastic which are currently being used for conventional uses but may be able to tap into the previously underutilised shape memory capabilities. All 4 materials were subjected to mechanical deformation in order to induce some form of shape change, after which, heat was the chosen stimulus to activate its shape memory, if any. Since the materials are largely main consumer products, its heating conditions and thermal properties are already known and can be obtained from the manufacturer’s catalogue. Thus, thermogravimetric analysis is not needed before determining the temperatures to test its shape memory properties. In this report, we delve straight into the mechanical deformations that include fracture tests and cyclic tests at different temperatures. The mechanical properties of said materials were categorized by compression loading/unloading tests. Possibly the most interesting phenomenon is stress whitening being reversed when subjected to heat. And this is apparent in writing transparency samples. In general, all 4 materials that were tested showed promising results when it comes to shape memory capabilities, which opens the doors for potential applications in sectors such as the biomedical sector.