Journal of Adhesion and Interface (접착 및 계면)

The Society of Adhesion and Interface, Korea (한국접착및계면학회)
권호 표지
DOI QR코드

DOI QR Code

Fabrication of Poly(methyl methacrylate) Beads Monolayer Using Rod-coater and Effects of Solvents, Surfactants and Plasma Treatment on Monolayer Structure

Rod 코팅을 이용한 Poly(methyl methacrylate) 비드의 단일층 형성 및 단일층 구조에 미치는 용매, 계면활성제, 플라즈마 처리의 영향

  • Kim, Da Hye (Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology) ;
  • Ham, Dong Seok (Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology) ;
  • Lee, Jae-Heung (Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology) ;
  • Huh, Kang Moo (Department of Polymer Science and Engineering, Chungnam National University) ;
  • Cho, Seong-Keun (Chemical Materials Solutions Center, Korea Research Institute of Chemical Technology)
  • 김다혜 (한국화학연구원 화학소재솔루션센터) ;
  • 함동석 (한국화학연구원 화학소재솔루션센터) ;
  • 이재흥 (한국화학연구원 화학소재솔루션센터) ;
  • 허강무 (충남대학교 고분자공학과) ;
  • 조성근 (한국화학연구원 화학소재솔루션센터)
  • Received : 2018.12.11
  • Accepted : 2018.12.21
  • Published : 2019.03.31
Download PDF
⟨ Previous Next ⟩

Abstract

Fabrication of monolayer is important method for enhancing physical and chemical characteristics such as light shielding and antireflection while maintaining thin film properties. In previous studies, monolayers were fabricated by various methods on small substrates, but processes were complicated and difficult to form monolayers with large area. We used rod coating equipment with a small amount of coating liquid to form a HCP (hexagonal closed packing) coating of PMMA beads on PET(poly(ethylene terephthalate)) substrate with $20cm{\times}20cm$ size. We observed that changes in morphologies of monolayers by using the solvents with different boiling points and vapor pressures, by adapting surfactants on particles and by applying plasma treatment on substrates. The coverage was increased by 20% by optimizing the coating conditions including meniscus of beads, control of the attraction - repulsion forces and surface energy. This result can potentially be applied to optical films and sensors because it is possible to make a uniform and large-scale monolayer in a simple and rapid manner when it is compared to the methods in previous studies.

균일한 단일층(monolayer)의 형성은 박막 두께에서의 특성을 유지하면서 차광, 반사방지 등의 물리적, 화학적 기능을 강화할 수 있는 중요한 수단이다. 이전 연구에서도 여러 코팅 방법으로 단일층을 구현하였으나, 공정이 복잡하고 대면적화 하는데 어려움이 있었다. 이에 본 연구에서는 소량의 용액으로 대면적 코팅이 가능한 로드 (rod) 코팅법을 사용하여, $20cm{\times}20cm$ PET 필름 기판 위에 마이크로미터 크기의 PMMA 비드를 가장 치밀한 형태인 HCP(hexagonal closed packing)가 되도록 코팅을 진행하였다. 끓는점과 증기압이 다른 용매의 사용과 계면활성제의 적용, 플라즈마 처리를 통한 기판 에너지의 변화를 통해 형성되는 단일층의 수준을 관찰하였다. 본 연구를 통해 비드의 메니스커스, 용매와 비드의 인-척력, 표면에너지를 포함한 코팅 조건을 최적화함으로써, 최종적으로 단위면적당 비드가 차지하는 정도인 입자의 커버리지를 초기 대비 약 20% 정도 향상시켰고, 단일층에 영향을 주는 인자들을 확인하였다. 본 결과는 기존에 연구되었던 코팅 방법에 비해 간단하고 빠르게 대면적의 단일층(monolayer)을 형성할 수 있기 때문에, 광학필름과 센서 등 첨단 분야로의 잠재적 응용 가능성이 높다.

Keywords

JGMHB1_2019_v20n1_1_f0001.png 이미지

Figure 1. Concept drawing of monolayer formations of particles; (a) ordering, (b) packing, (c) hexagonal closed pack (HCP).

JGMHB1_2019_v20n1_1_f0002.png 이미지

Figure 2. Coverage distribution of PMMA beads according to solvent polarity.

JGMHB1_2019_v20n1_1_f0003.png 이미지

Figure 3. Plot of average solubility parameters vs. polar solubility parameters different solvent types.

JGMHB1_2019_v20n1_1_f0004.png 이미지

Figure 4. SEM images of coating surface depending on whether PMMA beads are modified by surfactants. (left : ×500, right : ×1500) : (a) not modified PMMA beads, (b) modified with cationic surfactant, (c) modified with anionic surfactants.

JGMHB1_2019_v20n1_1_f0005.png 이미지

Figure 5. Surface images of PMMA beads modified by different DTABr contents observed by optical microscope (a) 0 wt%, (b) 0.2 wt%, (c) 1.2 wt%, (d) 2.2 wt%, (e) 4.0 wt%, (f) 8.0 wt%, (g) 12.5 wt%, (h) 16.0 wt.

JGMHB1_2019_v20n1_1_f0006.png 이미지

Figure 6. Changes of coverage of PMMA bead layers as a function of surfactant contents.

JGMHB1_2019_v20n1_1_f0007.png 이미지

Figure 7. Concept drawing of particle surface charge and inter-particular attraction depending on surfactant contents.

JGMHB1_2019_v20n1_1_f0008.png 이미지

Figure 8. Variation of the coverage as a function of water contact angle of PET surface.

JGMHB1_2019_v20n1_1_f0009.png 이미지

Figure 9. Surface morphologies of PMMA beads on various PET substrates according to plasma treatment conditions observed by optical microscope. (a) on bare PET, (b) on plasma treated PET by N2O Gas flow of 400 sccm, (c) on plasma treated PET by line speed of 1.0 m/min, (d) on plasma treated PET by power of 2500W.

JGMHB1_2019_v20n1_1_f0010.png 이미지

Figure 10. Optical properties of PET films coated with PMMA beads. (a) changes of parallel transmittance and haze according to process conditions, (b) reflectance spectra according to process conditions.

Table 1. Characteristics of various solvent by type

JGMHB1_2019_v20n1_1_t0001.png 이미지

References

  1. Sangmoo Jeong, Liangbing Hu, Hye Ryung lee, Eric Garnett, Jang wook choi, Yi Cul, Nano letter, 10, 2989 (2010) https://doi.org/10.1021/nl101432r
  2. Metin Sitti, Ronald S. Fearing, Journal of Adhesion Science and Technology, 17, 1055 (2003) https://doi.org/10.1163/156856103322113788
  3. Jiaxing Huang, Franklin Kim, Andrea R. Tao, Stephen Connor, Peidong Yang, Nature Materials, 4, 896 (2005) https://doi.org/10.1038/nmat1517
  4. Pilsung Pack, Preparation and Properties of Highlyordered Macroporous Silica Films with Monolayer, Changwon National University, 1-68 (2004)
  5. Jung Min Lee, In Woo Cheong,; Jung Hyun Kim, Applied Chemistry, 8, 438 (2004)
  6. In Woo Cheong, Jung Min Lee, Jung Hyun Kim, Polymer Science and Technology, 15, 48. (2004)
  7. Peyer A. Kralchevsky, Kuniaki Nagayama, Langmuir, 10, 23-36. (1994) https://doi.org/10.1021/la00013a004
  8. Hailin Cong, Weixiao Cao, Langmuir, 19, 8177 (2003) https://doi.org/10.1021/la0344480
  9. Peter A. Kralchevsky, Nikolai D. Denkov, Current Opinion in Colloid & Interface Science, 6, 383 (2001) https://doi.org/10.1016/S1359-0294(01)00105-4
  10. Jian Chena, Peitao Donga, Di Di, Chaoguang Wang, Haoxu Wang, Junfeng Wang, Xuezhong Wu, Applied Surface Science, 270, 6. (2013) https://doi.org/10.1016/j.apsusc.2012.11.165
  11. Y. Wang, L. Chena, H. Yang, Q. Guoc, W. Zhou, M. Tao, Solar Energy Materials and Solar Cells, 93, 85. (2009) https://doi.org/10.1016/j.solmat.2008.08.008
  12. Takashi Ogia, Luis Balam Modesto-Lopezb, Ferry Iskandara, Kikuo Okuyama, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 297, 71 (2007) https://doi.org/10.1016/j.colsurfa.2006.10.027
  13. Young Gun Ko, Dong Hun Shin, Gil Sun Lee, Ung Su Choi, Colloids and Surfaces A: Physicochemical and Engineering Aspects, 385, 188 (2011) https://doi.org/10.1016/j.colsurfa.2011.06.011
  14. Wang. Y, Chen. L, Yang. H, Guo. Q, Zhou. W, Tao. M, Materials Science Poland, 28, 467 (2010)
  15. Hwayoung Ko, Hae-Weon Lee, Joo-Sun Kim, Jooho Moon, Journal of the Korean Ceramic Society, 39, 981 (2002) https://doi.org/10.4191/KCERS.2002.39.10.981
  16. S. Rakers, L. F. Chi, H. Fuchs, Langmuir, 13, 7121 (1997) https://doi.org/10.1021/la970757c
  17. Antony S. Dimitrov, Tetsuya Miwa, Kuniaki Nagayama, Langmuir, 15, 5257 (1999) https://doi.org/10.1021/la990225r
  18. Hwa-young Ko, Hae-Weon Lee, Jooho Moona, Thin Solid Films, 447 (2004)
  19. P. Yimsiri, M.R. Mackley, Chemical Engineering Science, 61, 3496 (2006) https://doi.org/10.1016/j.ces.2005.12.018
  20. R.A. Weiss, X. Zhai, A.V. Dobrynin, Langmuir, 24, 5218 (2008) https://doi.org/10.1021/la8001509