Methods. Spin-coated films were prepared with a Mikasa MS-A100
spin coater. A drop of polymer solutions (100 g dm−3) containing
either HPIP (1) or 6-cyano HPIP (2; 0.5 w/w% with respect to
polymer) were spin-coated at 1000 rpm onto quartz plates and then dried in a vacuum at 80 °C for 12 h. Dilute PVA solutions (5.0 g dm−3
in 70 v/v% ethanol/water) containing higher concentrations of 2 (2, 5,
10, and 30 w/w% with respect to PVA) were spin-coated for preparing
films with higher content of 2 (thickness: ∼0.1 μm).