Optically Active Poly[2-(sec-butyl)aniline] Nanofibers Prepared via Enantioselective Polymerization

Area of Science:

• Polymer Chemistry
• Materials Science
• Chiral Synthesis

Background:

• Optically active polymers are crucial for advanced applications.
• Developing efficient synthesis routes for chiral polymers remains a challenge.

Purpose of the Study:

• To present a novel synthetic route for optically active poly[2-(sec-butyl) aniline] (PSBA) nanofibers.
• To demonstrate enantioselective polymerization of a racemic monomer.

Main Methods:

• In situ chemical oxidative polymerization of (±)-2-sec-buthylaniline.
• Use of (+)- or (-)-camphor sulfonic acid (HCSA) as a chiral dopant.
• Characterization using circular dichroism (CD) spectroscopy, scanning electron microscopy (SEM), and gel permeation chromatography (GPC).

Main Results:

• Successful synthesis of optically active PSBA nanofibers.
• Mirror-imaged CD spectra confirmed the formation of enantiomers.
• Enantioselective polymerization was achieved under specific conditions (0.025 M monomer, 1.5 M HCSA, 0 °C).
• Nanofibers exhibited uniform morphology (55 nm average diameter) and a molecular weight of 4680 g/mol.

Conclusions:

• The developed method provides a viable route to enantioselective synthesis of chiral polymer nanofibers.
• The study highlights the potential of camphor sulfonic acid in directing chiral polymerization.
• The resulting PSBA nanofibers possess desirable morphological and chiral properties.