Mechanisms of Strain-Induced Interfacial Strengthening of Wet-Spun Filaments

We investigate the mechanism of binding of dopamine-conjugated carboxymethyl cellulose (DA-CMC) with carbon nanotubes (CNTs) and the strain-induced interfacial strengthening that takes place upon wet drawing and stretching filaments produced by wet-spinning. The filaments are known for their tensile strength (as high as 972 MPa and Young modulus of 84 GPa) and electrical conductivity (241 S cm(-1)). The role of axial orientation in the development of interfacial interactions and structural changes, enabling shear load bearing, is studied by molecular dynamics simulation, which further reveals the elasto-plasticity of the system. We propose that the reversible torsion of vicinal molecules and DA-CMC wrapping around CNTs are the main contributions to the interfacial strengthening of the filaments. Such effects play important roles in impacting the properties of filaments, including those related to electrothermal heating and sensing. Our findings contribute to a better understanding of high aspect nanoparticle assembly and alignment to achieve high-performance filaments.

Automated summary

This study investigates the mechanism of binding between dopamine-conjugated carboxymethyl cellulose and carbon nanotubes, as well as the strain-induced interfacial strengthening in wet-spun filaments. The results reveal the reversible torsion of neighboring molecules and the wrapping of DA-CMC around CNTs as the main factors contributing to the interfacial strengthening of the filaments. These findings are significant for the development and improvement of high-performance fibers.