Article
  • The Variation of Structure and Physical Properties of XLPE during Thermal Aging Process
  • Lee M, Kim CH, Koo CS, Kim BR, Lee Y
  • 가교 폴리에틸렌의 열노화에 따른 구조와 물성의 변화
  • 이미영, 김철환, 구철수, 김복렬, 이영관
Abstract
The variation of chemical structure and physical properties of crosslinked polyethylene (XLPE) during thermal aging process was investigated. The formation of carbonyl functional group resulting from thermal oxidation reaction of XLPE was monitored using X-ray photoelectron spectroscopy and near infrared (NIR) spectroscopy. It was observed that the intensity of carbonyl peak observed at 1715 nm linearly increased with aging time in NIR spectroscopy. The linear relationship between NIR peak absorbance and aging time confirmed that NIR spectroscopy might be used as a proper tool for monitoring the aging process of polymeric materials. Also the formation of crosslinks during the aging process was monitored using thermal mechanical analysis, stress-strain test, and Shore hardness test. The change in the physical properties, such as the increase in the glass transition temperature from 110 to 132 ℃, the decrease in the strain from 265 to 110%, as well as the increase in the shore D hardness from 32 to 50, was observed during the aging process.

가교 폴리에틸렌을 열을 가하여 노화시킨 후 구조 및 물성의 변화를 조사하였다. 가교 폴리에틸렌의 열적 산화 반응으로 카보닐 그룹이 형성됨을 X-선 광전자 분광법과 근적외선 분광법을 이용하여 확인하였다. 노화 시간이 길어질수록 1715 nm에서 관찰되는 카보닐 피이크가 정량적으로 증가하는 것을 근적외선 분광법을 이용하여 관찰하였다. 열화 시간에 따른 흡수 피이크의 선형적인 관계로부터 근적외선 분광법이 고분자 재료의 열화 과정을 감시하는데 적합한 방법임을 확인할 수 있었다. 또한 노화에 의한 가교 결합의 발생과 그에 따른 물리적 성질의 변화를 TMA, 응력-변형 시험, 쇼어 경도 측정 방법을 이용하여 관찰하였다. 노화가 진행됨에 따라 유리 전이 온도가 110에서 132 ℃로 증가함을 관찰하였으며, 인장률은 265에서 110%로 점차 감소하고 쇼어 D 경도는 32에서 50으로 크게 증가하는 것을 관찰할 수 있었다.

Keywords: XLPE; thermal aging; NIR; XPS

References
  • 1. Chaudhari P, Dresselhau SM, Rev. Mod. Phys., 71, 2 (1999)
  •  
  • 2. Sun C, Zhang D, Wadsworth LC, Adv. Polym. Technol., 18(2), 171 (1999)
  •  
  • 3. Liston EM, Martinu L, Wertheimer MR, J. Adhes. Sci. Technol., 7, 1091 (1993)
  •  
  • 4. Choi DM, Park CK, Cho K, Park CE, Polymer, 38(25), 6243 (1997)
  •  
  • 5. Barlow, IEEE Trans. Electr. Insul., 7, 8 (1991)
  •  
  • 6. Phillips PJ, Karakelle M, Vatansever A, Polym. Commun., 25, 204 (1984)
  •  
  • 7. Steennis EP, Kreuger FK, IEEE Trans. Electr. Insul., 25, 989 (1990)
  •  
  • 8. Ceres BV, Schults KM, J. Appl. Polym. Sci., 29, 4183 (1984)
  •  
  • 9. Lee YD, Phillips PJ, J. Appl. Polym. Sci., 40, 263 (1990)
  •  
  • 10. Ieda M, IEEE Trans. Electr. Insul., 15, 206 (1980)
  •  
  • 11. Rasikawan S, Ishihara H, Shimizu N, IEEE Trans. Electr. Insul., 4, 597 (1994)
  •  
  • 12. Lee YD, Phillips PJ, IEEE Trans. Electr. Insul., 26, 171 (1991)
  •  
  • 13. Buchalla R, Schuttler CH, Bogl KW, J. Food Protection, 56, 991 (1993)
  •  
  • 14. Gao S, Zeng Y, J. Appl. Polym. Sci., 47, 2093 (1993)
  •  
  • 15. Li ZF, Netravali AN, J. Appl. Polym. Sci., 44, 319 (1992)
  •  
  • 16. Bai GJ, Weng YX, Hu XZ, J. Appl. Polym. Sci., 60(13), 2397 (1996)
  •  
  • 17. Bai GJ, Hu XZ, Yan Q, Polym. Bull., 36(4), 503 (1996)
  •  
  • 18. Wanh C, Hsiue G, J. Polym. Sci. A: Polym. Chem., 31, 1309 (1993)
  •  
  • 19. Whetsel KB, Appl. Spectrosc. Rev., 21, 1 (1986)
  •  
  • 20. Weyer LG, Appl. Spectrosc. Rev., 20, 1 (1985)
  •  
  • 21. Stark E, Luchter K, Margoshes M, Appl. Spectrosc. Rev., 22, 335 (1986)
  •  
  • 22. Miller CE, Appl. Spectrosc. Rev., 26, 277 (1991)
  •  
  • 23. Siesler HW, Macromol. Chem. Macromol. Symp., 5(2), 113 (1991)
  •  
  • 24. Lee KAB, Appl. Spectrosc. Rev., 28, 231 (1993)
  •  
  • 25. Hall JW, Grzybowski DE, Monfre SL, J. NIR Spectrosc., 1, 55 (1993)
  •  
  • 26. vanUum MPB, Lammers H, deKleijin JP, Macromol. Chem. Phys., 196, 2023 (1995)
  •  
  • 27. Khettry A, Hansen MG, Polym. Eng. Sci., 36(9), 1232 (1996)
  •  
  • 28. Church JS, O'Neill JA, Woodhead AL, Appl. Spectrosc., 52, 1039 (1998)
  •  
  • Polymer(Korea) 폴리머
  • Frequency : Bimonthly(odd)
    ISSN 0379-153X(Print)
    ISSN 2234-8077(Online)
    Abbr. Polym. Korea
  • 2023 Impact Factor : 0.4
  • Indexed in SCIE

This Article

  • 2003; 27(3): 249-254

    Published online May 25, 2003

  • Received on Feb 21, 2003
  • Accepted on May 13, 2003