The growth of spatially organized structures is of considerable fundamental interest, since it may provide us with important clues to the way in which organized structures form in Nature. A closer look at complex structures in insect wings and lizard toes reveal organized structured features at the microscopic scale. The organized structures in Nature are formed through evolutionary processes, and these complex molecules and features are built using molecular protein machinery. 

Synthetic polymers, that mimic biological materials in their designs, form organized structures too. We have demonstrated, for the first time, that nanostructured polymer thin films can be fabricated by an oblique angle polymerization method. We plan to develop these films with 3 methods (Figure 1).  

Figure 1.  Roadmap of Oblique Angle Polymerization 

These structures are composed of approximately 40,000,000 aligned columns (approximately 100-150 nm in diameter) per square millimeter similar to the gecko footpad or insect wing.These structures have high aspect ratio (~1000:1) and the production technique does not require any template, lithography method or a surfactant for deposition (Figure 2). The nanostructured polymer films are conformal to any surface. This approach allows us to tune the chemical properties of nanostructured surfaces and film morphology to control the physicochemical properties of the resulting films, such as hydrophobicity, porosity, electrochemistry, chemical reactivity, surface energy and crystallinity.Here is a simulation of the oblique angle polymerization (Ballistic Monte Carlo Simulation)MOVIE

We have recently functionalized nanostructured polymer films for controlled release and delivery of organics and synthetic molecules. Structured polymer brushes are envisioned to be useful in for specific controlled drug release, metallization (SERS and catalyst applications), tissue targeting as well as antifouling applications.

Here is a movie on superhydrophobicity of nanostructured poly(p-xylylene) film surface. You can see that water drops are easily sliding of the surface. Applications include self-decontaminating and self-cleaning surfaces. MOVIE

**If you want to learn more about nanostructured polymer films, click to the PDF's below or contact us. 


 

 

Figure 2.  Structured Poly-(p-xylyene) film and its applications

 

References : (Please note that the PDF files provided in this web site are copyrighted documents)

Cetinkaya, M., Malvakdar, N., Demirel, M.C., “Power-Law Scaling of Structured Poly(p-xylylene) Films Deposited by Oblique Angle”, JOURNAL OF POLYMER SCIENCE PART B: POLYMER PHYSICS, Vol. 46, pg 640-648, 2008. (PDF)

Demirel, M.C.,  “Emergent Properties of Spatially Organized Poly(P-xylylene) Films Fabricated by Vapor Deposition" COLLOIDS and SURFACES-A, Vol.321, pg. 121-124, 2008 (PDF)

Cetinkaya, M., Boduroglu, S., Demirel, M.C.  “Growth of Nanostructured Thin Films of Poly(p-xylylene) Derivatives by Vapor Deposition”, POLYMER, Vol.48, pg. 4130-4134, 2007 (PDF)

Demirel, M.C., So, E., Ritty, T.M, Naidu, S, Lakhtakia, A., "Fibroblast Cell Attachment and Growth on Nanoengineered Sculptured Thin Films", JOURNAL OF BIOMEDICAL MATERIALS RESEARCH-B, Vol 81B, pg. 219-223, 2007 (PDF)

Pursel, S., Horn, M.W., Demirel, M.C., Lakhtakia, A., “Growth of Sculptured Polymer Suwire Assemblies by Vapor Deposition”, Vol. 46, POLYMER, pg. 9544-9548, 2005 (PDF)

Demirel, M.C., Boduroglu S., Cetinkaya, M., Lakhtakia, A. “Spatially Organized Free-Standing Poly(P-xylylene) Nanowires Fabricated by Vapor Deposition”, LANGMUIR, Vol. 23, pg. 5861-5863, 2007(PDF)

Demirel, M.C., Cetinkaya, M., Singh, A., Dressick W.J.,  “A Non-Covalent Method for Depositing Nanoporous Metals via Spatially Organized Poly(P-xylylene) Films”, ADVANCED MATERIALS, Vol.19, pg.4495-4499, 2007 (PDF)

Boduroglu S., Cetinkaya, M., Dressick, W., Singh, A., Demirel, M.C., ”Controlling Wettability and Adhesion of Nanostructured Poly-(p-xylylene) Films", LANGMUIR, Vol.23,pg. 11391-11395, 2007 (PDF)

Mangan, A., Boduroglu, S., Wang, H., Demirel M.C., “Bio-Functionalization of Structured Poly(P-xylylene) Films”, submitted, 2008. (PDF)

Malvadkar N., Park, S., Macdonald, M., Wang, H., Demirel, M.C., "Catalytic activity of cobalt deposited on nanostructured Poly(p-xylylene) films", JOURNAL of POWER SOURCES, Vol. 182, pg. 323-328, 2008 (PDF)

Kao, P., Malvadkar N., Wang, H. Allara, D., Demirel, M.C., “Surface Enhanced Raman Detection of Bacteria on Metalized Nanostructured Poly(p-xylylene) Films ” Vol. 20, pg. 3562-3565, ADVANCED MATERIALS, 2008.  (PDF)

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