SC-CO2 ANNEALING OF BLOCK COPOLYMER THIN FILMS

ABATE A; GIANG THI VU; PIQUERAS M.; GOMEZ LR; SCHMID, F; VEGA DA

Buenos Aires

Simposio; FRONTIERS IN PHYSICAL SCIENCES. HUMBOLDT KOLLEG.; 2016

ICAS - Max Planck - Alexander von Humboldt Foundation.

Here we explore the use of supercritical (sc) carbon dioxide as an environmentallyfriendly solvent for controlling the self-assembly of block copolymer thin films. The highdiffusivity and solubility of sc-CO2 in the block copolymer system depress its glasstransition temperature, dilutes the network of topological entanglements and thus,enhances polymer chain mobility. In addition, the sc-CO2 reduces the preferentialinteraction between the substrate and one of the blocks and thus favors the appearance ofarrays of hexagonally packed cylinders, perpendicularly arranged with regards to thesubstrate. The mechanisms of pattern formation and the equilibrium configurations are ingood agreements with recent simulations using self-consistent field theory and timedependentGinzburg-Landau models for systems with competing interactions.