Fabrication of robust micro-patterned polymeric films via static breath-figure process and vulcanization

Here, we present the preparation of thermally stable and solvent resistant micro-patterned polymeric films via static breath-figure process and sequent vulcanization, with a commercially available triblock polymer, polystyrene-b-polyisoprene-b-polystyrene (SIS). The vulcanized honeycomb structured SIS films became self-supported and resistant to a wide range of organic solvents and thermally stable up to 350 °C for 2 h, an increase of more than 300 K as compared to the uncross-linked films. This superior robustness could be attributed to the high degree of polyisoprene cross-linking. The versatility of the methodology was demonstrated by applying to another commercially available triblock polymer, polystyrene-b-polybutadiene-b-polystyrene (SBS). Particularly, hydroxy groups were introduced into SBS by hydroboration. The functionalized two-dimensional micro-patterns feasible for site-directed grafting were created by the hydroxyl-containing polymers. In addition, the fixed microporous structures could be replicated to fabricate textured positive PDMS stamps. This simple technique offers new prospects in the field of micro-patterns, soft lithography and templates.

Graphical abstractStable and flexible honeycomb structured SIS film after 24 h vulcanization.Figure optionsDownload full-size imageDownload high-quality image (76 K)Download as PowerPoint slideResearch highlights► Preparation of micro-patterned polymeric films via static breath figure process with triblock copolymers, polystyrene-b-polyisoprene-b-polystyrene (SIS) and hydroxyl-containing polystyrene-b-polybutadiene-b-polystyrene (SBS-OH). ► Sequent vulcanization to improve chemical and thermal stability of the micro-structured polymeric films. ► Replication of fixed microporous structures to fabricate textured positive PDMS stamps.