Buckling of conductive layer within shape memory matrix

• Main Author: Tan, Zhong Jie
• Other Authors: Huang Weimin
• Format: Final Year Project
• Language: English
• Published: 2017
• Subjects: DRNTU::Engineering::Mechanical engineering
• Online Access: http://hdl.handle.net/10356/70794
• Institution: Nanyang Technological University

This report explores one of the most important type of polymers widely used in the industry, shape memory polymers (SMPs). SMPs has an unique ability called the shape memory effect (SME) which allows them to recover their original shape under an external stimulus such as heat even though their temporary shape is distorted. In this report, only two different types of SMPs were studied intensively, silicone with melting glue and silicone with thermoplastic polyurethane (TPU). The SME of the two types of SMPs were investigated by bonding an aluminium foil between two layers of substrate and varying factors such as thickness, composition of the materials, maximum tensile strain. By investigating the effects of the wrinkles on the foil caused by the buckling after shape recovery, the relationship between shape fixity, shape recovery and the amount of tensile strain were established. After characterizing the effects of the wrinkles, the instron machine was used to obtain the stress-strain curve of samples stretched to different amount of tensile strain at high temperature. By comparing the stress measured at that corresponding strain with the samples that were bonding together and performed cyclic testing at room temperature until fractured, an observation of the ultimate tensile strength and stress was made. However, more research can be examined to obtain a more accurate findings and conclusions on similar topics in the future. Furthermore, some products using such similar concept can be manufactured and widely used in the industry.