2 isopropanol ipa

Acetone HPLC grade $\ge 99.9\%$ , 2-isopropanol (IPA), and glycerol were obtained from Sigma-Aldrich (Oakville, ON, Canada). AMOPRIME and AMONIL MMS1 were provided by AMO. Photoresist Shipley S1828 and developer MF319 were bought from MICROPOSIT. The EPDM (ethylene propylene diene monomer) O-ring used to delimit the fluidic cell was obtained from PAUL and is identified by the product number NG0201023095.

PFO, synthesized by Suzuki coupling, was supplied by Cambridge Display Technology and used as received. The polymer had a number‐average molecular weight
Mn = 18 × 10³ g mol⁻¹ and a polydispersity index = 2.7, as determined by polystyrene‐equivalent gel permeation chromatography. The absolute molecular weight was calculated by scaling
Mn down by a factor of 2.7 due to the higher relative chain stiffness of PFO,17 giving an estimate of 17 fluorene repeat units per average chain. Toluene (HPLC grade, >99.7%, VWR), decahydronaphthalene (“decalin”; reagent grade, mixture of cis and trans isomers, Sigma‐Aldrich), cyclohexane (HPLC grade, >99%, VWR), and 2‐(iso‐)propanol (“IPA”; >99.5%, Sigma‐Aldrich) were used as received.