Microfabrication of conductive polymer nanocomposite for sensor applications
type: CreativeWork
description: This dissertation developed novel microfabrication techniques of conductive polymer nanocomposite and utilized this material as a functional element for various physical sensor applications. Microstructures of nanocomposite were realized through novel microcontact printing and laser ablation assisted micropatterning processes. Prototype devices including large-strain strain sensor and highly-sensitive pressure sensor were demonstrated showing distinct advantages over existing technologies. The polymer nanocomposite used in this work comprised elastomer poly(dimexylsiloxane) (PDMS) as polymer matrix and multi-walled carbon nananotubes (MWCNTs) as a conductive nanofiller. To achieve uniform distribution of carbon nanotubes within the polymer, an optimized dispersion process was developed, featuring a strong organic solvent—chloroform, which dissolved PDMS base polymer easily and allowed monodispersion of MWCNTs. Following material preparation, three novel approaches were employed to pattern microstructures of polymer nanocomposite, each of which held respective advantages over previous fabrication techniques. For example, microcontact printing, by using a pre-defined stamp, directly transfers nanocomposite patterns from the ink reservoir to a substrate. Therefore, it eliminates the need of repeated photolithography process for every sample, saving time and cost. For another example, two variations of the laser assisted screen printing technique with micropatterns defined by the programmable laser ablation of a thin polymer film, allowed direct filling of nanocomposite and required only a CAD drawing for each design of sensor sample. Two variations of this fabrication protocol realized both fully embedded nanocomposite structures in a bulk polymer, as well as protruding relief-patterns of the nanocomposite on a polymer surface. The sensing capability of the polymer nanocomposite is attributed to the unique combination of mechanical flexibility and electrical piezoresis…
abstract: This dissertation developed novel microfabrication techniques of conductive polymer nanocomposite and utilized this material as a functional element for various physical sensor applications. Microstructures of nanocomposite were realized through novel microcontact printing and laser ablation assisted micropatterning processes. Prototype devices including large-strain strain sensor and highly-sensitive pressure sensor were demonstrated showing distinct advantages over existing technologies. The polymer nanocomposite used in this work comprised elastomer poly(dimexylsiloxane) (PDMS) as polymer matrix and multi-walled carbon nananotubes (MWCNTs) as a conductive nanofiller. To achieve uniform distribution of carbon nanotubes within the polymer, an optimized dispersion process was developed, featuring a strong organic solvent—chloroform, which dissolved PDMS base polymer easily and allowed monodispersion of MWCNTs. Following material preparation, three novel approaches were employed to pattern microstructures of polymer nanocomposite, each of which held respective advantages over previous fabrication techniques. For example, microcontact printing, by using a pre-defined stamp, directly transfers nanocomposite patterns from the ink reservoir to a substrate. Therefore, it eliminates the need of repeated photolithography process for every sample, saving time and cost. For another example, two variations of the laser assisted screen printing technique with micropatterns defined by the programmable laser ablation of a thin polymer film, allowed direct filling of nanocomposite and required only a CAD drawing for each design of sensor sample. Two variations of this fabrication protocol realized both fully embedded nanocomposite structures in a bulk polymer, as well as protruding relief-patterns of the nanocomposite on a polymer surface. The sensing capability of the polymer nanocomposite is attributed to the unique combination of mechanical flexibility and electrical piezoresis…
author: Liu, Chaoxuan
keywords: Polymer nanocomposite, carbon nanotubes, sensor, microfabrication
date published: 2012-01-01T08:00:00Z
date modified: 2026-07-24T02:57:39Z
provider: Lousiana State University
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: Electrical and Computer Engineering

PropertyValue
property ID: DOI
value: 10.31390/gradschool_dissertations.459