Diana (Hanqiong) Hu

Graduate Student

Office: 226 Mason Lab

Phone: (203) 436-4059



Since August 2009, PhD student, Yale University, School of Engineering & Applied Science, Department of Chemical Engineering

June 2009, BSc in Polymer Science and Engineering, Zhejiang University, Department of Polymer Science and Engineering. BSc thesis: "Surface Controlled Polymerization on Polypropylene Membrane and its Anti-bacterial Property"

I am working on a novel method-solvent vapor permeation (SVP) for facile alignment of self-assembled structures in BCP films with thickness on the millimeter scale. The technique is based on pressure-driven transport of a solvent in the vapor phase through a polymer film, resulting in long-range order and alignment of the BCP interfaces parallel to the vapor flux. This fast-driven process is similar to the alignment induced by imposition of shear or extensional flows on swollen polymer melts. The polymer microstructure is aligned by the relative motion of solvent molecules past the polymer chains. We have successfully verified the idea using a simple setup. (Figure 1) The SAXS data demonstrate the formation of vertically aligned hexagonally packed cylinders on vapor permeation from an initially isotropic SEBS film. (Figure 2) The influence of the controlling parameters including temperature, pressure, flow, solvent, etc. is being explored in detail alongside the expected kinetic, morphological and molecular weight effects.


Figure 1 Schematic illustration of the experimental setup and of alignment of BCP domains via solvent permeation through the polymer film.

Figure 2 Two-dimensional SAXS data for SEBS films subjected to vapor flux 65 and 140 Celsius. The schematic shows the geometry of the scattering experiment with the red arrows denoting the incidence of X-rays.Vapor flux is along the z axis. Top row: parallel geometry. Buttom row: perpendicular. Left to right : 65, 140, and 140 Celsius - 250mm Hg.