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간헐 압축응력 완화를 이용한 가교 구조가 hydrogenated NBR 오링의 수명에 미치는 영향 연구

Effect of Cure System on the Life-time of Hydrogenated NBR O-ring using Intermittent Compression Stress Relaxation(CSR)

  • 이진혁 (부산대학교 고분자공학과) ;
  • 배종우 (한국신발피혁연구소 산업소재융합기술센터 고무연구팀) ;
  • 김정수 (한국신발피혁연구소 산업소재융합기술센터 고무연구팀) ;
  • 황태준 (한국신발피혁연구소 산업소재융합기술센터 고무연구팀) ;
  • 최유석 (부경대학교 고분자공학과) ;
  • 백광세 (엘라켐) ;
  • 조남주 (부산대학교 고분자공학과)
  • Lee, Jin-Hyok (Department of Polymer Engineering, Pusan National University) ;
  • Bae, Jong-Woo (Rubber Material Research Division, Korea Institute of Footwear & Leather Technology) ;
  • Kim, Jung-Su (Rubber Material Research Division, Korea Institute of Footwear & Leather Technology) ;
  • Hwang, Tae-Jun (Rubber Material Research Division, Korea Institute of Footwear & Leather Technology) ;
  • Choi, Yu-Seok (Department of Polymer Engineering, Pukyong National University) ;
  • Baek, Kwang-Sae (Elachem Co.) ;
  • Jo, Nam-Ju (Department of Polymer Engineering, Pusan National University)
  • 투고 : 2011.03.24
  • 심사 : 2011.05.02
  • 발행 : 2011.06.30

초록

Intermittent CSR 측정법을 이용하여 hydrogenated NBR(이하 HNBR) 오링의 노화 거동과 수명 예측에 관하여 연구하였다. HNBR 오링의 가교 구조는 황 가교와 퍼옥사이드 가교를 이용하여 각각 제조하였다. Intermittent CSR jig는 오링의 실제 사용환경을 고려하여 설계 제작하였다. 각 측정 조건에 따른 마찰 영향, 열 손실 영향 및 Mullins effect에 의한 intermittent CSR의 응력 거동 변화를 관찰하였다. 오링의 노화 거동은 $100{\sim}120^{\circ}C$에서의 가속 노화 연구를 통하여 관찰하였다. 고장조건 50%와 40%에 대하여 HNBR 오링은 선형 노화 거동을 나타내었으며, Arrhenius relationship을 만족시켰다. HNBR-S 오링의 활성화 에너지는 70.6 kJ/mol로 나타났으며, Arrhenius plot으로부터 오링의 예측 수명은 고장 조건 50%와 40%에 대하여 각각 31.1년과 33.7년으로 나타났다. HNBR-P 오링의 활성화 에너지는 72.1 kJ/mol로 나타났으며, Arrhenius plot으로부터 오링의 예측 수명은 고장 조건 50%와 40%에 대하여 각각 34.0년과 36.5년으로 나타났다. 황 가교에 비하여 퍼옥사이드 가교에서 고무의 노화 속도가 느리게 나타났으며, 활성화 에너지는 높게 나타났다.

Intermittent CSR testing was used to investigate the degradation of a hydrogenated NBR(HNBR) O-rings, and also the prediction of its life-time. The cure system of HNBR O-ring was controlled as sulfur cure and peroxide cure system. An intermittent CSR jig was designed taking into consideration the O-ring's environment under use. The testing allowed observation of the effects of friction, heat loss, and stress relaxation by the Mullins effect. Degradation of O-rings by thermal aging was observed between 100 and $120^{\circ}C$. In the temperature range of $100-120^{\circ}C$, O-rings showed linear degradation behavior and satisfied the Arrhenius relationship. The activation energy of HNBR-S was about 70.6 kJ/mol. From Arrhenius plots, predicted life-times of HNBR-S O-ring were 31.1 years and 33.7 years for 50% and 40% failure conditions, respectively. In case of HNBR-P, the activation energy was about 72.1kJ/mol, and predicted life-times were 34.0 years and 36.5 years for 50% and 40% failure conditions, respectively. The peroxide cure system showed slower degradation rate and higher activation energy than the sulfur cure system.

키워드

참고문헌

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