Contact
    Start Publications A pickering emulsion stabilized by chlorella microalgae as an ...
    ←  Publication Finder
    Attension

    A pickering emulsion stabilized by chlorella microalgae as an eco-friendly extrusion-based 3D printing ink processable under ambient conditions

    Year: 2021

    Journal: J. Colloid Interface Sci., Volume 582, JAN 15, page 81–89

    Authors: Kwak, Chaesu; Ryu, Seoung Young; Park, Hyunsu; Lim, Sehyeong; Yang, Jeewon; Kim, Jieun; Kim, Jin Hyung; Lee, Joohyung

    Organizations: Basic Science Research Program through National Research Foundation of Korea (NRF) - Ministry of Education [NRF-2018R1D1A1A02085492]; Nano.Material Technology Development Program through the National Research Foundation of Korea (NRF) - Ministry of Science, ICT and Future Planning [2009-0082580]

    Keywords: Pickering emulsion; Chlorella; Microalgae; 3D printing; Rheology

    Three-dimensional (3D) printing technology is actively utilized in various industrial fields because it facilitates effective and customizable fabrication of complex structures. An important processing route for 3D printing is the extrusion of inks in the form of colloidal suspensions or emulsions, which has recently attracted considerable attention because it allows for selection of a wide range of printing materials and is operable under ambient processing conditions. Herein, we investigate the 3D printability of complex fluids containing chlorella microalgae as an eco-friendly material for 3D printing. Two possible ink types are considered: aqueous chlorella suspensions and emulsions of oil and water mixtures. While the aqueous chlorella suspensions at high particle loading display the 3D-printable rheological properties such as high yield stress and good shape retention, the final structures after extruding and drying the suspensions under ambient conditions show a significant number of macroscopic defects, limiting their practical application. In contrast, the 3D structures produced from the oil-in-water Pickering emulsions stabilized by chlorella microalgae, which are amphiphilic and active at the oil-water interface, show significantly reduced defect formation. Addition of a fast-evaporable oil phase, hexane, is crucial in the mechanisms of enhanced cementation between the individual microalgae via increased inter-particle packing, capillary attraction, and hydrophobic interaction. Furthermore, addition of solid paraffin wax, which is crystalline but well-soluble in the hydrocarbon oil phase under ambient conditions, completely eliminates the undesirable defect formation via enhanced inter-particle binding, while maintaining the overall rheological properties of the emulsion. The optimal formulation of the Pickering emulsion is finally employed to produce a 3D scaffold of satisfactory structural integrity, suggesting that the chlorella-based ink, in the form of an emulsion, has potential as an eco-friendly 3D printing ink processable under ambient conditions. (C) 2020 Elsevier Inc. All rights reserved.
    View publication