Faculté des sciences

Secondary structure-induced micro- and macrophase separation in rod-coil polypeptide diblock, triblock, and star-block copolymers

Sánchez-Ferrer, Antoni ; Mezzenga, Raffaele

In: Macromolecules, 2010, vol. 43, no. 2, p. 1093–1100

Ten novel rod−coil block copolymers based on poly(γ-benzyl-l-glutamate) (PBLG), rod block, and poly(propylene oxide) (PPO), coil block, have been synthesized, and the influence on their secondary structure and solid-state organization have been studied in terms of their architecture (diblock, triblock, or star-block), molecular weight of the polymer coil block (from 2 to 5 kDa), and volume... Plus

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    Summary
    Ten novel rod−coil block copolymers based on poly(γ-benzyl-l-glutamate) (PBLG), rod block, and poly(propylene oxide) (PPO), coil block, have been synthesized, and the influence on their secondary structure and solid-state organization have been studied in terms of their architecture (diblock, triblock, or star-block), molecular weight of the polymer coil block (from 2 to 5 kDa), and volume fraction of the rod block (0.50 or 0.75). The degree of polymerization of the polypeptide segment into the arms of the block copolymers, DParm, strongly affects the final α-helical secondary structure and the corresponding self-assembling of the block copolymers. Below 20 amino acid residues, a mixture of secondary structures (α-helices, β-sheets, and unordered segments) and microphase separation of the blocks is present. Above 20 repeating units, the microphase separation goes together with macrophase separation of the pure α-helical secondary structure, which ends up into an orthogonal lamellar phase or rods.