Effect of molecular helical structure on self-growing and damping of single network κ-carrageenan hydrogel

Abstract

Molecular helical is ubiquitous in molecular structures, however, the impact of the structure on mechanical properties has yet to be extensively studied. In this study, we synthesized a single network κ-carrageenan (KC) hydrogel with the molecular double helix structure, and elucidated its unique self-enhancing and damping properties from a molecular structural perspective. During cycle tensile tests, the helical structure was stretched and entangled to form a directional arrangement, increasing the elastic modulus and achieving 'self-reinforcement'. Meanwhile, the molecular helices have a spring-like damping effect, allowing the hydrogel to dampen low-frequency noise while transmitting high-frequency signals. By utilizing the hydrogel to create electrodes for electrocardiogram (ECG) detection, we were able to effectively filter out noise generated by movements while retaining necessary signals. Our work thus presents a potential pathway bridging from microscopic molecular structure to macroscopic mechanical properties of materials.

Keywords: Damper; Molecular structure; Self-reinforcement; κ-Carrageenan.