Preparation of reactive three-dimensional microstructures via direct laser writing and thiol-ene chemistry.

Three-dimensional microstructures are fabricated employing the direct laser writing process and radical thiol-ene polymerization. The resin system consists of a two-photon photoinitiator and multifunctional thiols and olefins. Woodpile photonic crystals with 22 layers and a rod distance of 2 μm are fabricated. The structures are characterized via scanning electron microscopy and focused ion beam milling. The thiol-ene polymerization during fabrication is verified via infrared spectroscopy. The structures are grafted in a subsequent thiol-Michael addition reaction with different functional maleimides. The success of the grafting reaction is evaluated via laser scanning microscopy and X-ray photoelectron spectroscopy. The grafting density is calculated to be close to 200 molecules μm(-2) .

[1]  M. Wegener,et al.  Direct laser writing of three-dimensional photonic-crystal templates for telecommunications , 2004, Nature materials.

[2]  M. Wegener,et al.  Two‐Component Polymer Scaffolds for Controlled Three‐Dimensional Cell Culture , 2011, Advanced materials.

[3]  S. Linden,et al.  Photonic metamaterials by direct laser writing and silver chemical vapour deposition. , 2008, Nature materials.

[4]  Christopher N Bowman,et al.  Thiol-ene click chemistry. , 2010, Angewandte Chemie.

[5]  Brian J. Adzima,et al.  3D Photofixation Lithography in Diels-Alder Networks. , 2012, Macromolecular rapid communications.

[6]  C. Barner‐Kowollik,et al.  Dynamic Covalent Chemistry on Surfaces Employing Highly Reactive Cyclopentadienyl Moieties , 2011, Advanced materials.

[7]  M. G. Finn,et al.  Click Chemistry: Diverse Chemical Function from a Few Good Reactions. , 2001, Angewandte Chemie.

[8]  Charles E. Hoyle,et al.  Thiol–enes: Chemistry of the past with promise for the future , 2004 .

[9]  N. Clark,et al.  Formation and Surface Modification of Nanopatterned Thiol‐ene Substrates using Step and Flash Imprint Lithography , 2008 .

[10]  Hiroaki Misawa,et al.  In situ investigation of the shrinkage of photopolymerized micro/nanostructures: the effect of the drying process. , 2012, Optics letters.

[11]  G. Stucky,et al.  Highly Versatile and Robust Materials for Soft Imprint Lithography Based on Thiol‐ene Click Chemistry , 2008 .

[12]  Dong Yol Yang,et al.  Improvement of spatial resolution in nano-stereolithography using radical quencher , 2006 .

[13]  J. Fischer,et al.  Three‐dimensional optical laser lithography beyond the diffraction limit , 2013 .

[14]  Stefano Begolo,et al.  Rapid prototyping of multilayer thiolene microfluidic chips by photopolymerization and transfer lamination. , 2008, Lab on a chip.

[15]  Saulius Juodkazis,et al.  Three‐Dimensional Spiral‐Architecture Photonic Crystals Obtained By Direct Laser Writing , 2005 .

[16]  Kevin D. Belfield,et al.  Two-Photon Photoinitiated Polymerization , 2003 .

[17]  P. Grabek,et al.  Photocrosslinked norbornene–thiol copolymers: Synthesis, mechanical properties, and cure studies , 1992 .

[18]  E. Amis,et al.  Microfluidic platform for the generation of organic-phase microreactors. , 2005, Langmuir : the ACS journal of surfaces and colloids.

[19]  Shoji Maruo,et al.  Recent progress in multiphoton microfabrication , 2008 .