# Confinement-induced chirality in phase-separated achiral polymer solutions

## TL;DR

Achiral polymers can form chiral structures when confined, offering new ways to create chiral materials from non-chiral components.

## Contribution

Demonstrates chirality emergence in achiral polymers due to confinement and phase separation.

## Key findings

- Kinetically arrested phase separation in capillaries creates isotropic and chiral nematic segments.
- Chirality arises from geometry, surface anchoring, and polymer anisotropy.
- Catenoidal chiral structures resemble biological chiral morphologies.

## Abstract

Self-organization of polymers in constrained geometries largely determines their applications in high-strength materials, photonics, and electronics. Chiral organization under confinement is well established for polymers with intrinsic molecular chirality; however, it has not been observed for achiral polymers. Here, we report the emergence of chirality in spatially confined solutions of achiral rigid-rod polymers. We show that kinetically arrested phase separation of polymer solutions confined to narrow capillaries resulted in alternating segments of isotropic and chiral nematic phases. The chiral structure of the nematic segments originated from the interplay between the constrained geometry, surface anchoring, orientational wetting, and elastic anisotropy of rigid-rod polymers. The catenoidal shape of the chiral structure recapitulated the morphology of biological chiral structures. These findings provide insight into the organization of soft matter under spatial confinement and offer a straightforward way to form chiral structures from achiral synthetic polymers.

Achiral rigid-rod polymers self-organize into chiral structures under confinement.