Secondary Structure-Induced Micro- and Macrophase Separation in Rod-Coil Polypeptide Diblock, Triblock, and Star-Block Copolymers

作者：Sanchez Ferrer Antoni; Mezzenga Raffaele^*

来源：Macromolecules, 2010, 43(2): 1093-1100.

DOI：10.1021/ma901951s

Ten novel rod-coil block copolymers based on poly(gamma-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, strongly affects the final alpha-helical secondary structure and the corresponding self-assembling of the block copolymers. Below 20 amino acid residues, a mixture of secondary structures (alpha-helices, beta-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 alpha-helical secondary structure, which ends up into an orthogonal lamellar phase or rods.

• 出版日期2010-1-26