Issue
Korean Chemical Engineering Research,
Vol.49, No.3, 352-356, 2011
습도의 영향에 따른 PDMA-b-PS 친수성 블록공중합체 박막의 패턴 조절
The Vertical and Lateral Ordering of PDMA-b-PS Block Copolymer Thin film via Control of Relative Humidity
리빙 프리 라디칼 중합법은 ATRP, NMP, RAFT 등의 방법이 있으며, 지난 수 십년간 매우 빠르게 발전해 왔다. 그 중에서 RAFT 중합법은 다른 방법들에 비해 최근에 학문적으로 크게 주목 받고 있다. RAFT 중합법은 다른 리빙 프리 라디칼 중합법에 합성할 수 있는 단량체의 종류나 합성의 제한이 비교적 작아서, 다양한 기능성 고분자를 쉽게 중합할 수 있으며, 합성한 고분자의 분자량 분포 또한 좁게 만들 수 있는 장점이 있다. 따라서 RAFT 중합법을 통해 다양한 형태의 블록 공중합체, 댄드리머 등을 합성하는데 이용되고 있다. 이 논문에서는 위와 같은 RAFT 중합법을 이용해, 친수성 블록을 갖는 새로운 블록 공중합체를 합성한다. Poly(ethylene-b-styrene)와 poly(ethylene-b-metharylate-bstyrene) 같은 블록 공중합체 박막을 이용해 용매 증발법에 의한 높은 수준의 정렬도를 갖는 연구가 진행, 보고되었다. 그리고 위의 2가지 연구에서 습도가 정렬도에 큰 영향을 미치는 것으로 보고되고 있다. 하지만 위의 연구에서 친수성 블록에 의한 영향을 명확하게 규명하지 못했다. 따라서 이 논문에서는 다른 친수성 블록을 갖는 poly(N,Ndimethylacrylamide-b-styrene)를 RAFT 중합법에 의해 합성하고, 이를 이용해 박막 내에서 용매 증발법 중의 습도에 의한 영향을 일반화하고자 한다.
In this paper, we prepared new type of hydrophilic block copolymers that exhibit the long-ranged lateral ordering in thin film. It was previously demonstrated that poly(ethyleneoxide-b-styrene) and poly(ethyleneoxide-b-metharylate-b-styrene) block copolymer thin films have a high degree of lateral ordering after solvent annealing process. In these cases, the relative humidity plays an important role in long-ranged lateral ordering. However, the origin of the humidity effect on the orders of these hydrophilic block copolymers is not fully understood. To investigate the effect of the humidity further, we prepared other hydrophilic poly(N,N-dimethylacrylamide-b-styrene)(PDMA-b-PS) block copolymers via RAFT polymerization. As with PEO-containing block copolymers, PDMA-b-PS block copolymers exhibit the long-ranged lateral ordering after solvent annealing process.
[References]
  1. Bang J, Jeong U, Ryu DY, Russell TP, Hawker CJ, Adv. Mater., “Block Copolymer Nanolithography: Translation of Molecular Level Control to Nanoscale Patterns", 21(47), 4769, 2009
  2. Mansky P, Liu Y, Huang E, Russell TP, Hawker C, Science, “Controlling Polymer-Surface Interactions with Random Copolymer Brushes", 275(5305), 1458, 1997
  3. Huang E, Pruzinsky S, Russell TP, Mays J, Hawker CJ, Macromolecules, “Neutrality Conditions for Block Copolymer Systems on Random Copolymer Brush Surfaces", 32(16), 5299, 1999
  4. Ryu DY, Shin K, Drockenmuller E, Hawker CJ, Russell TP, Science., “A Generalized Approach to the Modification of Solid Surfaces", 308, 236, 2005
  5. Segalman RA, Yokoyama H, Kramer EJ, Adv. Mater., “Graphoepitaxy of Spherical Domain Block Copolymer Films", 13(15), 1152, 2001
  6. Kim SO, Solak HH, Stoykovich MP, Ferrier NJ, de Pablo JJ, Nealey PF, Nature., “Epitaxial Self-assembly of Block Copolymers on Lithographically Defined Nanopatterned Substrates", 424(6947), 411, 2003
  7. Morkved TL, Lu M, Urbas AM, Ehrichs EE, Jaeger HM, Mansky P, Russell TP, Science, “Local Control of Microdomain Orientation in Diblock Copolymer Thin Films with Electric Fields", 273(5277), 931, 1996
  8. Mansky P, DeRouchey J, Russell TP, Mays J, Pitsikalis M, Morkved T, Jaeger H, Macromolecules, “Large-Area Domain Alignment in Block Copolymer Thin Films Using Electric Fields", 31(13), 4399, 1998
  9. Wang JY, Xu T, Leiston-Belanger JM, Gupta S, Russell TP, Physical Review Letters., “Ion Complexation: A Route to Enhanced Block Copolymer Alignment with Electric Fields", 96(12), 128301, 2006
  10. Kim G, Libera M, Macromolecules, “Morphological Development in Solvent-Cast Polystyrene Polybutadiene Polystyrene (SBS) Triblock Copolymer Thin Films", 31(8), 2569, 1998
  11. Kim G, Libera M, Macromolecules, “Kinetic Constraints on the Development of Surface Microstructure in SBS Thin Films", 31(8), 2670, 1998
  12. Kim SH, Misner MJ, Russell TP, Adv. Mater., “Solvent-Induced Ordering in Thin Film Diblock Copolymer/Homopolymer Mixtures", 16(23-24), 2119, 2004
  13. Kim SH, Misner MJ, Xu T, Kimura M, Russell TP, Adv. Mater., “Highly Oriented and Ordered Arrays from Block Copolymers via Solvent Evaporation", 16(3), 226, 2004
  14. Bang J, Kim SH, Drockenmuller E, Misner MJ, Russell TP, Hawker CJ, J. Am. Chem. Soc., “Defect-Free Nanoporous Thin Films from ABC Triblock Copolymers", 128(23), 7622, 2006
  15. Kim SH, Misner MJ, Yang L, Gang O, Ocko BM, Russell TP, Macromolecules, “Salt Complexation in Block Copolymer Thin Films”, 39(24), 8473, 2006
  16. Park SC, Kim BJ, Hawker CJ, Kramer EJ, Bang J, Ha JS, Macromolecules, “Controlled Ordering of Block Copolymer Thin Films by the Addition of Hydrophilic Nanoparticles", 40(22), 8119, 2007
  17. Park SC, Jung H, Fukukawa KI, Campos LM, Lee K, Shin K, Hawker CJ, Ha JS, Bang J, J. Polym. Sci. A: Polym. Chem., “Highly Ordered Nanoporous Thin Films by Blending of PSt-b-PMMA Block Copolymers and PEO Additives as Structure Directing Agents", 46(24), 8041, 2008
  18. Bang J, Kim BJ, Stein GE, Russell TP, Li X, Wang J, Kramer EJ, Hawker CJ, Macromolecules, “Effect of Humidity on the Ordering of PEO-Based Copolymer Thin Films", 40(19), 7019, 2007
  19. Srinivasarao M, Collings D, Philips A, Patel S, Science., “Three-Dimensionally Ordered Array of Air Bubbles in a Polymer Film", 292(5514), 79, 2001