Science China Materials

, Volume 62, Issue 12, pp 1921–1933 | Cite as

Effect of ketyl radical on the structure and performance of holographic polymer/liquid-crystal composites

  • Xiaoyu Zhao (赵骁宇)
  • Shanshan Sun (孙姗姗)
  • Ye Zhao (赵晔)
  • Rong-Zhen Liao (廖荣臻)
  • Ming-De Li (李明德)Email author
  • Yonggui Liao (廖永贵)
  • Haiyan Peng (彭海炎)Email author
  • Xiaolin Xie (解孝林)


Holographic polymer/liquid-crystal composites, which are periodically ordered materials with alternative polymer-rich and liquid-crystal-rich phases, have drawn increasing interest due to their unique capabilities of reconstructing colored three-dimensional (3D) images and enabling the electro-optic response. They are formed via photopolymerization induced phase separation upon exposure to laser interference patterns, where a fast photopolymerization is required to facilitate the holographic patterning. Yet, the fast photopolymerization generally leads to depressed phase separation and it remains challenging to boost the holographic performance via kinetics control. Herein, we disclose that the ketyl radical inhibition is able to significantly boost the phase separation and holographic performance by preventing the proliferated diffusion of initiating radicals from the constructive to the destructive regions. Dramatically depressed phase separation is caused when converting the inhibiting ketyl radical to a new initiating radical, indicating the significance of ketyl radical inhibition when designing high performance holographic polymer composites.


liquid crystal ordered structures photopolymerization inhibition holography 



全息聚合物/液晶复合材料是由富聚合物相与富液晶相周期性排列而成的结构有序复合材料, 不仅具有独特的彩色3D图像存储功能, 还具有电光响应特性, 因此获得了广泛关注. 全息聚合物/液晶复合材料通过激光相干下的光聚合诱导相分离原位形成. 高的光聚合反应速率有利于全息加工, 但往往会抑制相分离. 因此, 发展新的动力学调控策略以提升全息聚合物/液晶复合材料的性能仍是一个挑战. 本研究发现, 羰基自由基阻聚可抑制引发自由基从相干亮区向相干暗区的传递, 进而显著提高相分离程度和全息性能. 消除羰基自由基导致全息聚合物/液晶复合材料性能下降, 也证实了羰基自由基阻聚在设计高性能全息聚合物/液晶复合材料中的重要性.



We thank the financial supports from the National Natural Science Foundation of China (51433002 and 51773073), HUST peak boarding program, the National Science Foundation (NSF) of Hubei Scientific Committee (2016CFA001) and the Fundamental Research Funds for the Central Universities (2019kfyRCPY089). We also thank the technical assistance from HUST Analytical & Testing Center.

Conflict of interest The authors declare no competing financial interest.

Supplementary material

40843_2019_9580_MOESM1_ESM.pdf (12.3 mb)
Effect of ketyl radical on the structure and performance of holographic polymer/liquid-crystal composites


  1. 1.
    Gabor D. A new microscopic principle. Nature, 1948, 161: 777–778Google Scholar
  2. 2.
    Gorkhover T, Ulmer A, Ferguson K, et al. Femtosecond X-ray Fourier holography imaging of free-flying nanoparticles. Nat Photon, 2018, 12: 150–153Google Scholar
  3. 3.
    Tikan A, Bielawski S, Szwaj C, et al. Single-shot measurement of phase and amplitude by using a heterodyne time-lens system and ultrafast digital time-holography. Nat Photon, 2018, 12: 228–234Google Scholar
  4. 4.
    Leite IT, Turtaev S, Jiang X, et al. Three-dimensional holographic optical manipulation through a high-numerical-aperture soft-glass multimode fibre. Nat Photon, 2017, 12: 33–39Google Scholar
  5. 5.
    Vyas S, Chia YH, Luo Y. Conventional volume holography for unconventional airy beam shapes. Opt Express, 2018, 26: 21979–21991Google Scholar
  6. 6.
    Melde K, Mark AG, Qiu T, et al. Holograms for acoustics. Nature, 2016, 537: 518–522Google Scholar
  7. 7.
    van den Heuvel M, Prenen AM, Gielen JC, et al. Patterns of diacetylene-containing peptide amphiphiles using polarization holography. J Am Chem Soc, 2009, 131: 15014–15017Google Scholar
  8. 8.
    Kobayashi Y, Abe J. Real-time dynamic hologram of a 3D object with fast photochromic molecules. Adv Opt Mater, 2016, 4: 1354–1357Google Scholar
  9. 9.
    Blanche PA, Bablumian A, Voorakaranam R, et al. Holographic three-dimensional telepresence using large-area photorefractive polymer. Nature, 2010, 468: 80–83Google Scholar
  10. 10.
    Ozaki M, Kato J, Kawata S. Surface-plasmon holography with white-light illumination. Science, 2011, 332: 218–220Google Scholar
  11. 11.
    Chen G, Ni M, Peng H, et al. Photoinitiation and inhibition under monochromatic green light for storage of colored 3D images in holographic polymer-dispersed liquid crystals. ACS Appl Mater Interfaces, 2017, 9: 1810–1819Google Scholar
  12. 12.
    Xie XL, Peng HY, Zhou XP, et al. Visible Light Photoinitiating System for Preparing High Diffraction Efficiency Hologram Optical Polymer Material. USA Patent, US 9753431 B2, 2017-09-05Google Scholar
  13. 13.
    Peng H, Bi S, Ni M, et al. Monochromatic visible light “photo-initibitor”: Janus-faced initiation and inhibition for storage of colored 3D images. J Am Chem Soc, 2014, 136: 8855–8858Google Scholar
  14. 14.
    Ni M, Peng H, Liao Y, et al. 3D image storage in photopolymer/ZnS nanocomposites tailored by “photoinitibitor”. Macromolecules, 2015, 48: 2958–2966Google Scholar
  15. 15.
    Li X, Ren H, Chen X, et al. Athermally photoreduced graphene oxides for three-dimensional holographic images. Nat Commun, 2015, 6: 6984Google Scholar
  16. 16.
    Luo Y, Gelsinger PJ, Barton JK, et al. Optimization of multiplexed holographic gratings in PQ-PMMA for spectral-spatial imaging filters. Opt Lett, 2008, 33: 566–568Google Scholar
  17. 17.
    Yu R, Li S, Chen G, et al. Monochromatic “photoinitibitor”-mediated holographic photopolymer electrolytes for lithium-ion batteries. Adv Sci, 2019, 6: 1900205Google Scholar
  18. 18.
    Shen W, Wang L, Chen G, et al. A facile route towards controllable electric-optical performance of polymer-dispersed liquid crystal via the implantation of liquid crystalline epoxy network in conventional resin. Polymer, 2019, 167: 67–77Google Scholar
  19. 19.
    Shen W, Wang L, Zhong T, et al. Electrically switchable light transmittance of epoxy-mercaptan polymer/nematic liquid crystal composites with controllable microstructures. Polymer, 2019, 160: 53–64Google Scholar
  20. 20.
    Zhao D, Zhou W, Cui X, et al. Alignment of liquid crystals doped with nickel nanoparticles containing different morphologies. Adv Mater, 2011, 23: 5779–5784Google Scholar
  21. 21.
    Hu X, de Haan LT, Khandelwal H, et al. Cell thickness dependence of electrically tunable infrared reflectors based on polymer stabilized cholesteric liquid crystals. Sci China Mater, 2017, 61: 745–751Google Scholar
  22. 22.
    Bunning TJ, Natarajan LV, Tondiglia VP, et al. Holographic polymer-dispersed liquid crystals (H-PDLCs). Annu Rev Mater Sci, 2000, 30: 83–115Google Scholar
  23. 23.
    White TJ, Natarajan LV, Tondiglia VP, et al. Monomer functionality effects in the formation of thiol-ene holographic polymer dispersed liquid crystals. Macromolecules, 2007, 40: 1121–1127Google Scholar
  24. 24.
    Peng H, Yu L, Chen G, et al. Liquid crystalline nanocolloids for the storage of electro-optic responsive images. ACS Appl Mater Interfaces, 2019, 11: 8612–8624Google Scholar
  25. 25.
    Ni M, Chen G, Wang Y, et al. Holographic polymer nano-composites with ordered structures and improved electro-optical performance by doping POSS. Compos Part B-Eng, 2019, 174: 107045Google Scholar
  26. 26.
    Yagci Y, Jockusch S, Turro NJ. Photoinitiated polymerization: Advances, challenges, and opportunities. Macromolecules, 2010, 43: 6245–6260Google Scholar
  27. 27.
    Dadashi-Silab S, Doran S, Yagci Y. Photoinduced electron transfer reactions for macromolecular syntheses. Chem Rev, 2016, 116: 10212–10275Google Scholar
  28. 28.
    Aguirre-Soto A, Lim CH, Hwang AT, et al. Visible-light organic photocatalysis for latent radical-initiated polymerization via 2e/1H+ transfers: Initiation with parallels to photosynthesis. J Am Chem Soc, 2014, 136: 7418–7427Google Scholar
  29. 29.
    Xi W, Pattanayak S, Wang C, et al. Clickable nucleic acids: Sequence-controlled periodic copolymer/oligomer synthesis by orthogonal thiol-X reactions. Angew Chem Int Ed, 2015, 54: 14462–14467Google Scholar
  30. 30.
    Zhang J, Xiao P. 3D printing of photopolymers. Polym Chem, 2018, 9: 1530–1540Google Scholar
  31. 31.
    Michalek L, Barner L, Barner-Kowollik C. Polymer on top: Current limits and future perspectives of quantitatively evaluating surface grafting. Adv Mater, 2018, 30: e1706321Google Scholar
  32. 32.
    Zhang J, Zivic N, Dumur F, et al. N-[2-(dimethylamino)ethyl]-1,8-naphthalimide derivatives as photoinitiators under LEDs. Polym Chem, 2018, 9: 994–1003Google Scholar
  33. 33.
    Yu J, Gao Y, Jiang S, et al. Naphthalimide aryl sulfide derivative norrish type I photoinitiators with excellent stability to sunlight under near-UV LED. Macromolecules, 2019, 52: 1707–1717Google Scholar
  34. 34.
    Yang H, Li G, Stansbury JW, et al. Smart antibacterial surface made by photopolymerization. ACS Appl Mater Interfaces, 2016, 8: 28047–28054Google Scholar
  35. 35.
    Deng J, Wang L, Liu L, et al. Developments and new applications of UV-induced surface graft polymerizations. Prog Polymer Sci, 2009, 34: 156–193Google Scholar
  36. 36.
    Zhang L, Du W, Nautiyal A, et al. Recent progress on nanos-tructured conducting polymers and composites: Synthesis, application and future aspects. Sci China Mater, 2018, 61: 303–352Google Scholar
  37. 37.
    Fouassier JP, Allonas X, Burget D. Photopolymerization reactions under visible lights: Principle, mechanisms and examples of applications. Prog Org Coatings, 2003, 47: 16–36Google Scholar
  38. 38.
    Grotzinger C, Burget D, Jacques P, et al. Photopolymerization reactions initiated by a visible light photoinitiating system: Dye/amine/bis(trichloromethyl)-substituted-1,3,5-triazine. Macromol Chem Phys, 2001, 202: 3513–3522Google Scholar
  39. 39.
    Peng H, Yu L, Chen G, et al. Low-voltage-driven and highly-diffractive holographic polymer dispersed liquid crystals with spherical morphology. RSC Adv, 2017, 7: 51847–51857Google Scholar
  40. 40.
    Stoll S, Schweiger A. Easyspin, a comprehensive software package for spectral simulation and analysis in EPR. J Magn Reson, 2006, 178: 42–55Google Scholar
  41. 41.
    Peng H, Ni M, Bi S, et al. Highly diffractive, reversibly fast responsive gratings formulated through holography. RSC Adv, 2014, 4: 4420–4426Google Scholar
  42. 42.
    Peng H, Nair DP, Kowalski BA, et al. High performance graded rainbow holograms via two-stage sequential orthogonal thiol—click chemistry. Macromolecules, 2014, 47: 2306–2315Google Scholar
  43. 43.
    Winter HH, Chambon F. Analysis of linear viscoelasticity of a crosslinking polymer at the gel point. J Rheology, 1986, 30: 367–382Google Scholar
  44. 44.
    Scott TF, Kowalski BA, Sullivan AC, et al. Two-color single-photon photoinitiation and photoinhibition for subdiffraction photolithography. Science, 2009, 324: 913–917Google Scholar
  45. 45.
    Frisch MJ, Trucks GW, Schlegel HB, et al. Gaussion, D.01. Wallingford CT: Gaussion, Inc. 2013Google Scholar
  46. 46.
    Yamaji M, Oshima J, Hidaka M. Verification of the electron/proton coupled mechanism for phenolic H-atom transfer using a triplet π,π* carbonyl. Chem Phys Lett, 2009, 475: 235–239Google Scholar
  47. 47.
    Christensen SK, Chiappelli MC, Hayward RC. Gelation of copolymers with pendent benzophenone photo-cross-linkers. Macromolecules, 2012, 45: 5237–5246Google Scholar
  48. 48.
    Li MD, Du Y, Chuang YP, et al. Water concentration dependent photochemistry of ketoprofen in aqueous solutions. Phys Chem Chem Phys, 2010, 12: 4800–4808Google Scholar
  49. 49.
    McIntire GL, Blount HN, Stronks HJ, et al. Spin trapping in electrochemistry. 2. Aqueous and nonaqueous electrochemical characterizations of spin traps. J Phys Chem, 1980, 84: 916–921Google Scholar
  50. 50.
    Odian G. Radical Chain Polymerization. In Principles of Polymerization, 4th ed. Hoboken, New Jersey: John Wiley & Sons, Inc. 2004. P198–349Google Scholar
  51. 51.
    Church DF. Substituent effects on nitroxide hyperfine splitting constants. J Org Chem, 1986, 51: 1138–1140Google Scholar
  52. 52.
    Sargent FP, Gardy EM. Spin trapping of radicals formed during radiolysis of aqueous solutions. Direct electron spin resonance observations. Can J Chem, 1976, 54: 275–279Google Scholar
  53. 53.
    Ni ML, Peng HY, Xie XL. Structure regulation and performance of holographic polymer dispersed liquid crystals. Acta Polym Sin, 2017, 48: 1557–1573Google Scholar
  54. 54.
    Peng H, Chen G, Ni M, et al. Classical photopolymerization kinetics, exceptional gelation, and improved diffraction efficiency and driving voltage in scaffolding morphological H-PDLCs afforded using a photoinitibitor. Polym Chem, 2015, 6: 8259–8269Google Scholar
  55. 55.
    Ni M, Chen G, Sun H, et al. Well-structured holographic polymer dispersed liquid crystals by employing acrylamide and doping ZnS nanoparticles. Mater Chem Front, 2017, 1: 294–303Google Scholar
  56. 56.
    Kabatc J, Czech Z, Kowalczyk A. The application of halomethyl 1,3,5-triazine as a photoinitiator or co-initiator for acrylate monomer polymerization. J Photochem Photobiol A-Chem, 2011, 219: 16–25Google Scholar
  57. 57.
    He M, Huang X, Zeng Z, et al. Phototriggered base proliferation: A highly efficient domino reaction for creating functionally photo-screened materials. Macromolecules, 2013, 46: 6402–6407Google Scholar

Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Xiaoyu Zhao (赵骁宇)
    • 1
  • Shanshan Sun (孙姗姗)
    • 2
  • Ye Zhao (赵晔)
    • 1
  • Rong-Zhen Liao (廖荣臻)
    • 1
  • Ming-De Li (李明德)
    • 2
    Email author
  • Yonggui Liao (廖永贵)
    • 1
  • Haiyan Peng (彭海炎)
    • 1
    Email author
  • Xiaolin Xie (解孝林)
    • 1
  1. 1.Key Lab for Material Chemistry of Energy Conversion and Storage, Ministry of Education, School of Chemistry and Chemical Engineering, and National Anti-Counterfeit Engineering Research CenterHuazhong University of Science and Technology (HUST)WuhanChina
  2. 2.Department of Chemistry and Key Laboratory for Preparation and Application of Ordered Structural Materials of Guangdong ProvinceShantou University (STU)ShantouChina

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