Journal of the Microelectronics and Packaging Society (마이크로전자및패키징학회지)

The Korean Microelectronics and Packaging Society (한국마이크로전자및패키징학회)
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Polyurea Cross-linked Silica Aerogel with Improved Mechanical Strength by Applying a Precursor Having a Plurality of Amino Groups

복수의 아민기를 가지는 전구체를 적용하여 기계적 강도를 향상시킨 폴리우레아 가교 실리카 에어로겔

  • Lee, Wonjun (Department of Materials Science and Engineering, Kangwon National University) ;
  • Kim, Taehee (Department of Materials Science and Engineering, Yonsei University) ;
  • Choi, Haryeong (Department of Materials Science and Engineering, Yonsei University) ;
  • Kim, Jiseung (Department of Materials Science and Engineering, Kangwon National University) ;
  • Lee, Hong-Sub (Department of Advanced Materials Engineering for Information and Electronics, Kyung Hee University)
  • 이원준 (강원대학교 신소재공학과) ;
  • 김태희 (연세대학교 신소재공학과) ;
  • 최하령 (연세대학교 신소재공학과) ;
  • 김지승 (강원대학교 신소재공학과) ;
  • 이홍섭 (경희대학교 정보전자신소재공학과)
  • Received : 2022.10.17
  • Accepted : 2022.10.24
  • Published : 2022.12.30
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Abstract

Aerogel is a material having a nanopore structure based on a high porosity. Due to this high porosity, it has excellent properties not found in conventional materials, but its application has been limited due to low mechanical strength. Therefore, to improve the mechanical strength of the aerogel, polyurea crosslinking was introduced and a precursor having an amine group essential for polyurea polymer formation was selected to synthesize a polyurea crosslinked aerogel composite. In addition, the crosslinking of polyurea was adjusted according to the number of amine groups present in aminosilane. It was confirmed through various analyses that the nanopore structure of the aerogel was maintained to have mesopores. The aerogel thus formed was able to improve the mechanical strength by about two times, and it was confirmed through field emission scanning electron microscope analysis that a one-dimensional polymer was formed on the silica aerogel surface through the introduction of ethylene diamine. The one-dimensional polymer thus formed has improved mechanical properties, resulting in securing an elastic modulus of about 2.66 MPa.

에어로겔은 높은 기공률과 나노기공구조를 갖는 물질이다. 이러한 높은 기공률로 인해 기존의 소재에서 볼 수 없는 뛰어난 특성을 보유하고 있지만 낮은 기계적 강도로 인해 적용이 제한되어왔다. 따라서 이러한 에어로겔의 기계적 강도의 향상을 위해 본 연구에서는 폴리우레아 가교결합을 도입하고 폴리우레아 고분자 형성에 필수적인 아민기를 갖는 전구체를 선택하여 폴리우레아가 가교결합된 에어로겔 복합체를 합성하였다. 또한, aminosilane에 존재하는 아민기의 수에 따라 폴리우레아의 가교결합을 조절하였고 다양한 분석을 통해 에어로겔이 나노기공구조를 유지하며 mesopore를 갖는다는 것을 확인하였다. 이렇게 형성된 에어로겔은 약 2배의 기계적 강도 향상을 나타내었고 Ethylene diamine의 도입을 통해 실리카 에어로겔 표면에 1차원의 고분자가 성장하는 것을 field emission scanning electron microscope 분석을 통해 확인하였다. 이렇게 형성된 1차원의 고분자는 기계적 특성을 향상시켜 약 2.66 MPa의 elastic modulus를 확보하는 결과를 도출하였다.

Keywords

Acknowledgement

이 성과는 정부(과학기술정보통신부)의 재원으로 한국연구재단의 지원을 받아 수행된 연구임(No. 2020R1A5A1019131).

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