Functional properties of stretchable conductive ink (SCI) with varying substrate

Mohamed Mustafa, Muhamad Asyraf (2022) Functional properties of stretchable conductive ink (SCI) with varying substrate. Project Report. Universiti Teknikal Malaysia Melaka, Melaka, Malaysia. (Submitted)

	Text (24 Pages) Functional properties of stretchable conductive ink (SCI) with varying substrate.pdf - Submitted Version Download (917kB)
	Text (Full text) Functional properties of stretchable conductive ink (SCI) with varying substrate.pdf - Submitted Version Restricted to Repository staff only Download (2MB)

Abstract

Stretchable conductive ink (SCI) is a functional material that enables the conductive ink film to have better electronic conductivity after stretching and folding. This project aims to investigate the effect of different polymer substrates on the functional properties of SCI. First, SCI's electrical and mechanical samples with varying GNP filler loading on Polyethylene (PET) and thermoplastic (TPU) substrates were prepared and tested. More specifically, the range of GNP filler loading used in this research is 5 wt.%, 7.5 wt.%, and 10 wt.%. Before the electrical and mechanical testing, the formulated SCI with different GNP filler loading was subjected to viscosity test by using a digital viscometer (MODEL 52DV). Besides, the hydrophobicity of the formulated SCI was investigated on the asreceived PET and TPU substrate through a contact angle test using self-fabricated contact angle measuring. Then, the sample was characterised using a four-point probe to determine the SCI's sheet resistance (Rs), which refers to ASTM F390 as a guideline; meanwhile, mechanical properties were characterised through a quantitative 180° peel test using a universal testing machine. By formulating SCI using different GNP filler loading, the viscosity increases as the filler loading increases; however, low viscosity is not appropriate with the stencil printing method and affects the electrical properties of the printed SCI on the substrate. The electrical properties of SCI printed on TPU and PET substrate show a decrease in sheet resistance with increasing GNP filler loading, from 5 wt. % to 10 wt.%. However, the SCI printed on the TPU substrate exhibit better conductivity than the SCI printed on the PET substrate. There is a reduction in adhesion strength from the peel test with increasing GNP filler loading. In addition, the results suggest that the SCI exhibited higher adhesion strength when printed onto the PET substrates than on TPU substrates, possibly because of the hydrophilic nature of the polymer material. Such finding is directly correlated with the degree of wetting, based on the contact angle measured on PET, which is low and yield high adhesion strength. Overall, it can be concluded that the SCI printed on different substrates affect the functional properties of the SCI.

Actions (login required)

View Item