Hydroxy terminated polystyrene ps oh

Cylinder-forming polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) BCP with a molar mass (Mn) of PS and PMMA of 46 and 21 kg/mol, respectively, was purchased along with polydispersity (PDI; Mw/Mn of 1.09) and hydroxy-terminated polystyrene (PS-OH) (Mn: 33.5 kg/mol and PDI: 1.08) from Polymer Source, Inc. (Dorval, QC, Canada). Anhydrous toluene sourced from Aldrich (St. Louis, MO, USA) was used to solvate the block copolymer and PS-OH. The resulting polymer solution was heated to 60 °C for 1 h, and then allowed to cool to room temperature.

Hydroxy-terminated polystyrene (PS-OH) (number-average
molecular weight, M_n = 10 kg mol^–1, M_w/M_n =
1.09, Mw: weight-average molecular weight), PS-b-PEO
diblock copolymer (M_nPS = 24 kg mol^–1, M_nPEO = 24.5 kg mol^–1, M_w/M_n = 1.09, f_PS = 0.49), PS
(M_n = 16 kg mol^–1, M_w/M_n = 1.03), and
PEG (M_n = 10 kg mol^–1, M_w/M_n =
1.01) were purchased from Polymer Source Inc. and were used without
further purification. Silicon ⟨100⟩ p-type wafers with
a native oxide layer were used as substrates. Fe₂(NO₃)3·9H₂O (iron(III) nitrate nonahydrate), Ni(NO₃)₃·6H₂O (nickel hydrate hexahydrate),
toluene (CHROMASOLV, for HPLC, 99.9%), and ethanol (dehydrated, 200
proof) were purchased from Sigma-Aldrich and used without further
purification unless otherwise stated. De-ionized water was used wherever
necessary.