Next Article in Journal
Concepts for Developing Physical Gels of Chitosan and of Chitosan Derivatives
Next Article in Special Issue
Influence of Structure-Directing Additives on the Properties of Poly(methylsilsesquioxane) Aerogel-Like Materials
Previous Article in Journal
Development of a 3D Co-Culture System as a Cancer Model Using a Self-Assembling Peptide Scaffold
Previous Article in Special Issue
Prevention of the Aggregation of Nanoparticles during the Synthesis of Nanogold-Containing Silica Aerogels
Article

Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution

Laboratory of Inorganic Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece
*
Author to whom correspondence should be addressed.
Received: 3 July 2018 / Revised: 30 July 2018 / Accepted: 3 August 2018 / Published: 6 August 2018
(This article belongs to the Special Issue Aerogels 2018)
We report the room temperature synthesis of spherical millimeter-size polyurea (PUA) aerogel beads. Wet-gels of said beads were obtained by dripping a propylene carbonate solution of an aliphatic triisocyanate based on isocyanurate nodes into a mixture of ethylenediamine and heavy mineral oil. Drying the resulting wet spherical gels with supercritical fluid (SCF) CO2 afforded spherical aerogel beads with a mean diameter of 2.7 mm, and a narrow size distribution (full width at half maximum: 0.4 mm). Spherical PUA aerogel beads had low density (0.166 ± 0.001 g cm–3), high porosity (87% v/v) and high surface area (197 m2 g–1). IR, 1H magic angle spinning (MAS) and 13C cross-polarization magic angle spinning (CPMAS) NMR showed the characteristic peaks of urea and the isocyanurate ring. Scanning electron microscopy (SEM) showed the presence of a thin, yet porous skin on the surface of the beads with a different (denser) morphology than their interior. The synthetic method shown here is simple, cost-efficient and suitable for large-scale production of PUA aerogel beads. View Full-Text
Keywords: aerogels; Desmodur N3300; ethylenediamine; polyurea; spherical beads aerogels; Desmodur N3300; ethylenediamine; polyurea; spherical beads
Show Figures

Graphical abstract

MDPI and ACS Style

Chriti, D.; Raptopoulos, G.; Papastergiou, M.; Paraskevopoulou, P. Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution. Gels 2018, 4, 66. https://doi.org/10.3390/gels4030066

AMA Style

Chriti D, Raptopoulos G, Papastergiou M, Paraskevopoulou P. Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution. Gels. 2018; 4(3):66. https://doi.org/10.3390/gels4030066

Chicago/Turabian Style

Chriti, Despoina; Raptopoulos, Grigorios; Papastergiou, Maria; Paraskevopoulou, Patrina. 2018. "Millimeter-Size Spherical Polyurea Aerogel Beads with Narrow Size Distribution" Gels 4, no. 3: 66. https://doi.org/10.3390/gels4030066

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Search more from Scilit
 
Search
Back to TopTop