Design and Morphological Investigation of High-χ Catechol-Containing Styrenic Block Copolymers
Guillaume Pino, Cian Cummins, Daniele Mantione, Nils Demazy, Alberto Álvarez‐Fernández, Stefan Guldin, Guillaume Fleury, Georges Hadziioannou, Éric Cloutet, Cyril Brochon
Abstract
We report the synthesis of multifunctional block copolymers (BCPs) showing a high Flory–Huggins interaction parameter (χ), which enable sub-10 nm line-space structures for a low degree of polymerization (N). The high χ BCPs are based on a poly(3,4-dihydroxystyrene)–block-poly(4-trimethylsilylstyrene) (PDHS-b-PTMSS) architecture. The controlled synthesis of the PDHS-b-PTMSS precursors was performed using user-friendly sequential nitroxide mediated polymerization (NMP) of poly(3,4-diacetoxystyrene) and block-poly(4-trimethylsilylstyrene) (PDAS-b-PTMSS). Thereafter, acid-catalyzed deprotection of the acetoxy moieties produced a library of PDHS-b-PTMSS BCPs with molecular weights ranging from 2.1 to 44.5 kg/mol. Bulk lamellar and cylindrical structures with periodicities as small as 8 nm were revealed by small-angle X-ray scattering. Moreover, PDHS-b-PTMSS thin films were assembled using solvent vapor annealing to define 10 nm line-space patterns in favorable conditions, i.e., at 20 °C for 20 min. In summary, our work brings further knowledge to the BCP toolbox for next-generation nanomanufacturing needs.