Experimental evidence of a transition from a sponge-like to a foam-like nanostructure in water-rich L phases.

J Colloid Interface Sci

Institute of Physical Chemistry, University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany. Electronic address:

Published: November 2021

Hypothesis: The micrometer-sized gas bubbles of a liquid foam with a dispersed gas phase of > 74 vol% are polyhedral and surrounded by a continuous aqueous phase. The structure of a water-rich microemulsion with a water phase of > 74 vol% normally consists of oil droplets in water or is bicontinuous. We hypothesize that at these high water contents polyhedral water droplets in oil can also exist.

Experiments: We (a) carried out phase studies on the water-rich side of the phase diagram of the quaternary system water/NaCl - hexyl methacrylate - AOT, because AOT is known for its propensity to form water-in-oil structures and hexyl methacrylate can be polymerized, (b) measured the electrical conductivities and viscosities, and (c) visualized the nanostructure with freeze-fracture electron microscopy (FFEM).

Findings: We found narrow 1-phase regions emanating from the L phase of the oil-free water/NaCl - AOT system by adding small amounts of oil. In these regions the conductivities become extremely low and the viscosities are extremely high. In addition, FFEM images clearly show the foam-like nanostructure.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jcis.2021.05.063DOI Listing

Publication Analysis

Top Keywords

foam-like nanostructure
8
phase of > 74 vol%
8
hexyl methacrylate
8
phase
6
experimental evidence
4
evidence transition
4
transition sponge-like
4
sponge-like foam-like
4
nanostructure water-rich
4
water-rich phases
4

Similar Publications

Long-term static dissolution experiments, lasting up to ∼1500 days, were conducted on International Simple Glass (ISG) and SON68 glass under hyperalkaline pH, at 70 °C, and at a very high glass surface area to solution volume ratio. The study compared (1) glass dissolution kinetics, (2) secondary phase formation, and (3) the microstructure of the altered glass and secondary phase interface. Boron release indicated rapid initial dissolution followed by a slowdown mainly due to a significant pH drop.

View Article and Find Full Text PDF

Solid Wood Modification toward Anisotropic Elastic and Insulative Foam-Like Materials.

ACS Nano

March 2024

Bioproducts Institute, Department of Chemical & Biological Engineering, The University of British Columbia, 2360 East Mall, Vancouver, British Columbia V6T 1Z3, Canada.

The methods used to date to produce compressible wood foam by top-down approaches generally involve the removal of lignin and hemicelluloses. Herein, we introduce a route to convert solid wood into a super elastic and insulative foam-like material. The process uses sequential oxidation and reduction with partial removal of lignin but high hemicellulose retention (process yield of 72.

View Article and Find Full Text PDF

Innovative materials and technologies capable of extraction and recovery of technologically relevant metal ions from various water sources, such as lakes, oceans, ponds, or wastewater reservoirs, are in great demand. Polymer beads are among the most well-known solid-phase adsorbents and ion exchangers employed in metal ion recovery. On the other hand, hydrogels are an emerging platform for producing innovative adsorbents, which are environmentally friendly and biocompatible materials.

View Article and Find Full Text PDF

Foam-like NiMo coatings were produced from an inexpensive mixture of Ni, Al, and Mo powders atmospheric plasma spraying. The coatings were deposited onto stainless-steel meshes forming a highly porous network mainly composed of nanostructured Ni and highly active NiMo. High material loading (200 mg cm) with large surface area (1769 cm per cm) was achieved without compromising the foam-like characteristics.

View Article and Find Full Text PDF

Bioactive Glass-Ceramic Scaffolds Coated with Hyaluronic Acid-Fatty Acid Conjugates: A Feasibility Study.

J Funct Biomater

January 2023

Institute of Materials Physics and Engineering, Department of Applied Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino, Italy.

Promoting bone healing is a key challenge in our society that can be tackled by developing new implantable biomaterials provided with regenerative properties. In this work, the coating of three-dimensional porous glass-derived scaffolds with hyaluronic acid (HA)-fatty acids was investigated for the first time. The starting scaffolds, based on bioactive silicate glass, were produced by foam replication followed by sintering; then, HA-palmitate and HA-oleate conjugate coatings were deposited on the scaffold struts through a dipping procedure.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!