利用介電泳效應研製具重覆記憶功能之CNT/PDMS壓力與溫度感測器

A novel CNT-PDMS-based pressure and temperature sensor with resistivity retaining and recovering by using dielectrophoresis effect

陳永明(Yung-Ming Chen)

指導教授 ： 楊燿州

國立臺灣大學/工學院/機械工程學研究所/碩士(2010年)

https://doi.org/10.6342/NTU.2010.00979

摘要

在本研究中，我們率先提出了一種複合記憶及清除功能之電阻式壓力與溫度感測器，此感測材料是由導電高分子構成，我們將奈米碳管(carbon nanotubes)與奈米銀粉(silver nano-particles)分散在聚二甲基矽氧烷 (polydimethylsiloxane, PDMS)中製作成導電高分子溶液，再將此溶液滴於電極層上並施加交流電壓進行介電泳，奈米碳管受介電泳力的影響，排列於電極之間並且形成奈米碳管導電網路，待高分子固化成型後即完成此新型壓力感測器的製作。本感測單元具有獨特的電阻感測機制：當感測單元承受壓力時，導電高分子內的奈米碳管導電網路因受壓而破壞，而造成感測單元的電阻率上升，而當壓力移除後電阻率不因壓力的去除而回復，若再次進行介電泳，被破壞的奈米碳管導電網路將可重新構成，使感測單元恢復初始電阻率。此外，感測單元對於溫度上升造成電阻率變化，以及使用介電泳恢復初始電阻率，皆有相同的感測機制。在本研究中，我們展示了感測單元的特性及重複性，並且探討不同電極間距造成之影響，此外，我們也發展了 可撓式壓力感測陣列，並利用感測陣列之壓力分佈圖展示影像記憶及清除功能。此感測器可望廣泛應用於智慧型足跡記憶地毯、壓力感測器、溫度感測器、加速度開關、溫度開關等相關產品之研製。

關鍵字

導電高分子 ； 壓力感測器 ； 觸覺感測器 ； 介電泳 ； 奈米碳管 ； 聚二甲基矽氧烷

並列摘要

In this work, we present novel resistive pressure and temperature sensors with reversible signal tracking capabilities. The sensing material was prepared by dispersing multi-walled carbon nanotubes (CNTs) and silver nano-particles through polydimethylsiloxane (PDMS) polymer with the assistance of the dielectrophoresis (DEP) technique. When the sensing element is pressed, a number of conductive CNT networks within the polymer are broken, thereby increasing the resistivity of the element. The polymer retains resistivity following the removal of the external force, and resistivity can be recovered to the original value using DEP to reform the conductive CNT networks. Similar resistivity behaviors induced by temperature elevation and DEP were also observed. This study demonstrates the performance and repeatability of the proposed sensing elements and investigates the characteristics of devices with various electrode gaps. We also fabricated flexible tactile sensor array and demonstrated image retaining and erasing capabilities. The potential applications of the sensor include reusable footstep tracking carpets, inertia switches, temperature switches, and other applications.

並列關鍵字

Conductive polymer ； pressure sensor ； tactile sensor ； dielectrophoresis ； carbon nanotube ； PDMS

參考文獻

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