Electrospinning of Cyclic Olefin Copolymer for the Production of Highly Aligned Dye‐Doped Optical Fibers
Cyclic olefin copolymer (COC, Topas 5013, with 75% norbornene) has special properties like high glass transition temperature, low moisture uptake, chemical inertness, and a high degree of transmission in UV range, making it competitive with other materials such as poly (methyl methacrylate) and polycarbonate for the production of optical devices. Electrospinning provides a facile way to produce fibers. In order to generate highly aligned fibers fulfilling the requirements for optical applications, stable-jet electrospinning can be used, in which the bending instabilities are suppressed. However, electrospinning of COC fibers by is still a major challenge due to the lack of suitable solvents. The influence of various solvents on the fiber formation is investigated. The addition of salts enhances the spinnability of the COC solution. By utilizing binary-solvent systems with the ratio of 2:8 (v/v), morphology and alignment of fibers are significantly improved, as visualized via scanning electron microscopy. The binary-solvent systems that content nonpolar and polar solvents also provide dispersibility for both organic dyes and inorganic nanoplatelets with hydrophobic ligand shells. By adding such dyes and nanoplatelets during fiber fabrication process, dye-doped COC fibers can be produced without compromising the optical performance of the dyes and nanoplatelets.