Insoluble Patterns of Cross-Linkable Conjugated Polymers from Blend Demixing in Spin Cast Films

Abstract

Insoluble patterns of cross-linkable conjugated polymers, CPs, are obtained from spin coating their blends with polystyrene, PS, following an approach first demonstrated for poly [2-methoxy-5-(2 0 -ethyl)hexyloxy-2,4-phenylenevinylene] (MEH-PPV) by Castro et al. (Chem. Mater. 2006, 18, 5504). Taking advantage of the CP and PS tendency to phase separate, we make use of CP functionality to be crosslinked, so PS can be removed, leaving behind a solvent-resistant pattern. Columnar, spike, and porous structures can be obtained. Furthermore, we show that these patterns morphologies and dimensions can be controlled by adjusting the experimental conditions and the PS molecular weight. We present strategies to tune cross-linkable CP's films morphologies aiming for applications in organic solar cells and light-emitting devices.

Solution‐Processable Donor‐Acceptor‐Donor Oligomers with Cross‐Linkable Functionality

“…In particular, OPP has been extensively used in the cross‐linking of a wide range of oxetane‐functionalized conjugated polymers and small molecules, allowing, for instance, the fabrication of multilayer and pixelated OLED structures . In previous works, we have also shown the use of OPP to cross‐link oxetane‐functionalized copolymers of polyfluorenes and derivatives of P3HT . However, in the case of the P3HT system, we have observed a decrease of PV cells efficiencies upon cross–linking, which can be, at least in part, related to the presence of OPP (or its residues) in the active blends.…”

Insoluble porous conjugated polymer films via phase separation and photo‐crosslinking for the trace detection of 2,4‐dinitrotoluene

“…Porous films were prepared in three steps: (i) fabrication of films by spin‐coating PFC1/polystyrene (PS; = 3500) blend solutions onto quartz plates; (ii) photo‐crosslinking of the coumarin groups in the side chains of PFC1; and (iii) removal of PS from the cross‐linked blend films of PFC1/PS. In the first step, solutions of PFC1 (12 mg mL −1 ) and PS (12 mg mL −1 ) were prepared in toluene/THF (1:1 v/v), respectively.…”

Crosslinked Semiconductor Polymers for Photovoltaic Applications

“…This is among the highest PCEs reported for OPVs using crosslinked active layers. [34] In the context of oxetane functionalization, it is noteworthy that, although it is generally assumed that this mechanism requires the exposure to an acid, [14,35] Knauer et al [15] showed that crosslinking via oxetane groups can be achieved by prolonged heating, yielding a fully crosslinked and long-term stable BHJ cell.…”