Unravelling the Acoustic and Thermal Responses of Perfluorocarbon Liquid Droplets Stabilized with Cellulose NanofibersShow others and affiliations
2019 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, no 40, p. 13090-13099Article in journal (Refereed) Published
Abstract [en]
The attractive colloidal and physicochemical properties of cellulose nanofibers (CNFs) at interfaces have recently been exploited in the facile production of a number of environmentally benign materials, e.g. foams, emulsions, and capsules. Herein, these unique properties are exploited in a new type of CNF-stabilized perfluoropentane droplets produced via a straightforward and simple mixing protocol. Droplets with a comparatively narrow size distribution (ca. 1-5 μm in diameter) were fabricated, and their potential in the acoustic droplet vaporization process was evaluated. For this, the particle-stabilized droplets were assessed in three independent experimental examinations, namely temperature, acoustic, and ultrasonic standing wave tests. During the acoustic droplet vaporization (ADV) process, droplets were converted to gas-filled microbubbles, offering enhanced visualization by ultrasound. The acoustic pressure threshold of about 0.62 MPa was identified for the cellulose-stabilized droplets. A phase transition temperature of about 22 °C was observed, at which a significant fraction of larger droplets (above ca. 3 μm in diameter) were converted into bubbles, whereas a large part of the population of smaller droplets were stable up to higher temperatures (temperatures up to 45 °C tested). Moreover, under ultrasound standing wave conditions, droplets were relocated to antinodes demonstrating the behavior associated with the negative contrast particles. The combined results make the CNF-stabilized droplets interesting in cell-droplet interaction experiments and ultrasound imaging.
Place, publisher, year, edition, pages
American Chemical Society , 2019. Vol. 35, no 40, p. 13090-13099
Keywords [en]
Bubbles (in fluids), Cellulose, Elastic waves, Nanocellulose, Nanofibers, Physicochemical properties, Ultrasonic imaging, Ultrasonic testing, Vaporization, Acoustic droplet vaporization, Cellulose nanofibers, Droplet interaction, Environmentally benign, Experimental examination, Narrow size distributions, Ultrasonic standing waves, Ultrasound standing waves, Drops
National Category
Natural Sciences
Identifiers
URN: urn:nbn:se:ri:diva-40537DOI: 10.1021/acs.langmuir.9b02132Scopus ID: 2-s2.0-85072992475OAI: oai:DiVA.org:ri-40537DiVA, id: diva2:1361917
Note
Funding details: Kungliga Tekniska Högskolan, KTH; Funding text 1: A.J.S. would like to acknowledge the KTH starting grant for financial support.
2019-10-172019-10-172023-05-22Bibliographically approved