화학공학소재연구정보센터
홈 로그인 로그아웃 연락처 사이트맵
Polymer(Korea), Vol.43, No.2, 196-203, March, 2019
DOI10.7317/pk.2019.43.2.196  Export Citation
반응성 액정 혼합물의 조성에 따른 분자 배열 연구
Effects of Composition of Reactive Liquid Crystal Mixture on Molecular Arrangements
정재현, 김석현, 이승혁, 조민기, 왕혁식, 송기국†
  • 경희대학교 정보전자신소재공학과, 영상정보소재기술연구센터
Jae Hyun Jung, Seok Hyeon Kim, Seung Hyuk Lee, Min Ki Cho, Hyuck Sik Wang, and Kigook Song†
  • Department of Advanced Materials Engineering for Information and Electronics, Materials Research Center for Information Display, Kyung Hee University, Yongin, Gyeonggi-do 446-701, Korea
E-mail:
초록
광반응성 네마틱 액정 LC242(2-methyl-1,4-phenylene bis(4-(((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoate))와 분자 크기가 상대적으로 작은 액정 5CB(4'-pentyl-[1,1'-biphenyl]-4-carbonitrile), 분자구조는 액정과 유사하지만 액정이 아닌 PBN(4-phenylbenzonitrile)을 이용하여 액정혼합물을 제작하였다. 두 혼합물의 온도에 따른 분자 배열 변화를 편광 FTIR 분광실험을 이용하여 비교 조사하였다. 온도가 증가함에 따라 액정상에서 뿐만 아니라 경화시킨 액정필름에서도 분자들이 액정 축의 방향은 유지하지만 배열 정도가 감소하였다. 액정성을 띠지 않는 PBN도 액정 5CB와 비슷하게 LC242 액정의 네마틱 배열 사이에 끼어들어 같이 배열이 되며 온도에 따른 움직임도 동일하게 나타났지만, order parameter 값으로 계산한 분자들의 배열 정도는 5CB에 비하여 낮게 나타났다.
Polarized FTIR spectroscopy experiments were carried out to investigate the effects of temperature on molecular arrangement of liquid crystal mixtures. Photo-reactive nematic liquid crystal LC242 (2-methyl-1,4-phenylene bis(4- (((4-(acryloyloxy)butoxy)carbonyl)oxy)benzoate)) was compared with a mixture of 5CB (4'-pentyl-[1,1'-biphenyl]-4-carbonitrile) having a relatively small molecular size and a mixture of PBN (4-phenylbenzonitrile) which is similar in molecular structure but not liquid crystal. As the temperature increased, the orientation of the liquid crystal axes remained the same in the liquid crystal film as well as in the cured liquid crystal film, but the degree of alignment decreased. PBN was interposed between the nematic arrays of LC242 similarly to 5CB, and the movement according to the temperature was the same. However, the order of the PBN molecules calculated by the order parameter value was lower than that of 5CB.
Keywords:reactive liquid crystal;mixtures;LC alignment;FTIR
  1. Lub J, Broer DJ, Wegh RT, Peeters E, van der Zande BMI, Mol. Cryst. Liq. Cryst., 429, 77 (2005)
  2. Kwon DW, Lim YJ, Jeon EJ, Kim DH, Kim JH, Kumar P, Lee MH, Lee SH, Curr. Appl. Phys., 11(3), 725 (2011)
  3. Chandrasekhar S, Liquid Crystals, 2nd edition, Cambridge University Press, Cambridge, 1992.
  4. Chandrasekhar S, Liquid Crystals, 2nd edition, Cambridge University Press, Cambridge, 1992.
  5. Yeh P, Gu C, Optics of Liquid Crystal Displays, John Wiley & Sons, Canada, 1999.
  6. Lee M, Bae JW, Song K, Polym. Korea, 39(1), 185 (2015)
  7. Wu LH, Luo S, Hsu CS, Wu ST, Jpn. J. Appl. Phys., 39, 5899 (2000)
  8. Hoke CD, Mori H, Bos PJ, Jpn. J. Appl. Phys., 38, L642 (1999)
  9. Suna Z, Qina A, Chena Z, Wanga Y, Liq. Cryst., 37, 345 (2010)
  10. Wu WY, Wang CC, Fuh AY, Opt. Express, 16, 17131 (2008)
  11. Painter PC, Coleman MM, Koenig JL, The Theory of Vibrational Spectroscopy and Its Application to Polymeric Materials, John Wiley & Sons Inc., New York, 1982.
  12. Ok J, Song K, Polym. Korea, 20(6), 1042 (1996)
  13. Jung JH, Bae JW, Song K, Polym. Korea, 40(5), 823 (2016)
  14. Kamal T, Park SY, Chem. Commun., 50, 2030 (2014)
  15. Bae JW, Song K, Polym. Korea, 39(4), 690 (2015)
  16. Jung G, Seo I, Lee M, Choi SW, Song K, Polym. Korea, 34(3), 242 (2010)
  17. Jung G, Lee M, Seo I, Song K, Polym. Korea, 35(3), 272 (2011)
  18. Lee M, Shin MY, Kim SH, Song K, Polym. Korea, 35(5), 493 (2011)
  19. Toriyama K, Dunmur DA, Mol. Phys., 56, 479 (1985)