Authors: V. Parvathy
Affilation: Univeristy of Queensland, Australia
Pages: 778 - 782
Keywords: diblock thin films, perpendicular orientation, molar mass
The motivation of this paper is to show the dependence of the morphology on the composition of the copolymers and to explore and understand the influence of morphological features in the nanoscale structure to tailor made the properties of the materials, quantifying the surface energies is of beyond the scope of this study.<br>Primary aim is to achieve the perpendicular orientation (periodic structure inside the film plane) by removing or balancing all interfacial action to study the inner film surface. <br>Discussed the efforts in manipulating and controlling the orientation of the nanoscopic domains for diblock polymers of poly (2-Hydroxyethyl methacrylate) and poly (n-butyl methacrylate) with macro-RAFTs of hydrophilic PHEMA and hhydrophobic BMA.<br>The control of orientation of the structures is a major challenge, a number of studies have been reported on thin films of lamellar and cylindrical polystyrene-poly (alkylmethacrylate) films on Si substrates, where the lamellae and cylinders have a strong tendency to orient parallel to the film surface.(1) Several attempts have been performed to eliminate commensurability, by e.g. applying electric fields, (2) or by choosing non-selective walls, (3) or pre-patterned surfaces(4), as all these approaches require additional efforts; a spontaneous formation of lateral structures would be desirable which is is achieved with diblock polymer films with molar mass sufficiently high lead to the formation of nano structured surfaces.<br> <br><br>Reference: <br> <br>(1) Thum-Albeecht , T., ; Schotter, J,; Kastle,G.A,; Emley, N,; Shibauchi,T,; Krusin-Elbaum,L,; Guraini, K,;Black ,C.T,; Tuminen, M.T,; Russell,T.P. Science 2000, 290.<br>(2) Bates , F. S. Science 1991, 251, 898.<br>(3) Sohn, B. H., ; Yun, S.H. Polymer 2002, 43, 2507.<br>(4) Knoll, A., ; Horvat ,A,; Lyakhova,K.S,; Krausch, G,; Sevink, G.J.A,; Zvelindovsky, .A.V,; Magerle, R. Phys.Rev.lett 2002, 89.