Science of Emotion and Sensibility (감성과학)

Korean Society for Emotion and Sensibility (한국감성과학회)
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Fabrication of Strain Sensor Based on Graphene/Polyurethane Nanoweb and Respiration Measurement

그래핀/폴리우레탄 나노웹 기반의 스트레인센서 제작 및 호흡측정

  • 이효철 (연세대학교 의류환경학과) ;
  • 조현선 (연세대학교 의류환경학과) ;
  • 이유진 (연세대학교 의류환경학과) ;
  • 장은지 (연세대학교 의류환경학과) ;
  • 조길수 (연세대학교 의류환경학과)
  • Received : 2018.12.03
  • Accepted : 2019.01.30
  • Published : 2019.03.31
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Abstract

The purpose of this study is to develop a strain sensor based on a nanoweb by applying electrical conductivity to a polyurethane nanoweb through the use of Graphene. For this purpose, 1% Graphene ink was pour-coated on a polyurethane nanoweb and post-treated with PDMS (Polydimethylsiloxane) to complete a wearable strain sensor. The surface characteristics of the specimens were evaluated using a field emission scanning electron microscope (FE-SEM) to check whether the conductive material was well coated on the surface of the specimen. Electrical properties of the specimens were measured by using a multimeter to measure the linear resistance of the specimen and comparing how the line resistance changes when 5% and 10% of the specimens are tensioned, respectively. In order to evaluate the performance of the specimen, the gauge factor was obtained. The evaluation of the clothing was performed by attaching the completed strain sensor to the dummy and measuring the respiration signal according to the tension using MP150 (Biopac system Inc., USA) and Acqknowledge (ver. 4.2, Biopac system Inc., U.S.A.). As a result of the evaluation of the surface characteristics, it was confirmed that all the conductive nanoweb specimen were uniformly coated with the Graphen ink. As a result of measuring the resistance value according to the tensile strength, the specimen G, which was treated with just graphene had the lowest resistance value, the specimen G-H had the highest resistance value, and the change of the line resistance value of the specimen G and the specimen G-H is increased to 5% It is found that it increases steadily. Unlike the resistance value results, specimen G showed a higher gauge rate than specimen G-H. As a result of evaluation of the actual clothes, the strain sensor made using the specimen G-H measured the stable peak value and obtained a signal of good quality. Therefore, we confirmed that the polyurethane nanoweb treated with Graphene ink plays a role as a breathing sensor.

본 연구의 목적은 그래핀(Graphene)을 사용하여 폴리우레탄 나노웹(Polyurethane Nanoweb)에 전기전도성을 부여하고, 이를 이용하여 나노웹 기반의 스트레인센서(Strain Sensor)를 개발하는 것이다. 이를 위해 1% 그래핀 잉크를 폴리우레탄 나노웹에 푸어코팅(Pour-coating)한 후 PDMS(Polydimethylsiloxane)로 후처리를 하여 착용 가능한 스트레인센서를 완성하였다. 시료 표면에 전도성 물질이 잘 코팅되었는지 확인하기 위해 전계방사형 주사전자현미경(FE-SEM)를 이용하여 시료의 표면 특성을 평가하였다. 시료의 전기적 특성 평가는 멀티미터(Multimeter)를 사용하여 시료의 선저항(Linear Resistance)을 측정하고, 시료를 각각 5%, 10% 인장하였을 때 선저항이 어떻게 변하는지 비교하였다. 또한 시료의 성능을 평가하고자 게이지율(Gauge Factor)을 구하였다. 착의평가 실험은 완성된 스트레인센서를 더미에 착용시킨 후 MP150(Biopac system Inc., U.S.A.)과 Acqknowledge(ver. 4.2, Biopac system Inc., U.S.A.)를 사용해 인장에 따른 호흡신호를 측정하였다. 표면 특성을 평가한 결과, 모든 전도성 나노웹 시료들이 그래핀 잉크로 균일하게 코팅되어있음을 확인하였다. 인장에 따른 저항값 측정 결과, 그래핀을 처리한 시료인 시료 G가 가장 낮은 저항값을, 그래핀을 처리한 후 열처리를 한 시료인 시료 G-H가 가장 높은 저항값을 가졌고, 시료 G와 시료 G-H의 경우 길이가 5%, 10%로 늘어남에도 선저항값의 변화가 안정적으로 증가하는 것으로 나타났다. 저항값 결과와는 달리, 시료 G가 시료 G-H보다 더 높은 게이지율을 보였다. 실제로 착의평가 결과, 시료 G-H를 이용해 만든 스트레인센서가 안정된 Peak값으로 측정되어 좋은 품질의 신호를 얻었다. 그러므로 본 연구를 통해 그래핀 잉크를 처리한 폴리우레탄 나노웹이 호흡 센서로서의 역할을 충분히 수행하는 것을 확인하였다.

Keywords

References

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