AI Article Synopsis

Article Abstract

The micelle aggregation numbers (N(agg)) of several series of cationic oligomeric surfactants were determined by time-resolved fluorescence quenching (TRFQ) experiments, using advantageously 9,10-dimethylanthracene as fluorophore. The study comprises six dimeric ("gemini"), three trimeric, and two tetrameric surfactants, which are quaternary ammonium chlorides, with medium length spacer groups (C(3)-C(6)) separating the individual surfactant fragments. Two standard cationic surfactants served as references. The number of hydrophobic chains making up a micellar core is relatively low for the oligomeric surfactants, the spacer length playing an important role. For the dimers, the number decreases from 32 to 21 with increasing spacer length. These numbers decrease further with increasing degree of oligomerization down to values of about 15. As for many conventional ionic surfactants, the micelles of all oligomers studied grow only slightly with the concentration, and they remain in the regime of small micelles up to concentrations of at least 3 wt %.

Download full-text PDF

Source
http://dx.doi.org/10.1021/la052414hDOI Listing

Publication Analysis

Top Keywords

oligomeric surfactants
12
aggregation numbers
8
cationic oligomeric
8
time-resolved fluorescence
8
fluorescence quenching
8
spacer length
8
surfactants
6
numbers cationic
4
surfactants time-resolved
4
quenching study
4

Similar Publications

Emulsion Polymerization of Styrene to Polystyrene Nanoparticles with Self-Emulsifying Nanodroplets as Nucleus.

Langmuir

January 2025

Research Center for Water Resources and Interface Science, School of Chemistry and Molecular Engineering, East China Normal University, Shanghai 200062, China.

The mechanism of the emulsion polymerization of styrene to polystyrene nanoparticles (PSNPs) remains a subject of debate. Herein, a series of reaction parameters with different surfactant concentrations, monomer contents, temperatures, and equilibration times were investigated to understand the formation mechanism of PSNPs, which demonstrate a correlation between the properties of PSNPs and the mesostructure of the premix. Cooling the model systems with self-emulsifying nanodroplets (SENDs) in the early reaction stages resulted in the hollow polystyrene spheres (H-PSSs), ruptured PSNPs, and dandelion-like PSNPs, further indicating that the oil nanodroplets are the key sites for the formation of PSNPs.

View Article and Find Full Text PDF

ConspectusSynthetic extracellular matrix (ECM) engineering is a highly interdisciplinary field integrating materials and polymer science and engineering, chemistry, cell biology, and medicine to develop innovative strategies to investigate and control cell-matrix interactions. Cellular microenvironments are complex and highly dynamic, changing in response to injury and disease. To capture some of these critical dynamics , biomaterial matrices have been developed with tailorable properties that can be modulated in the presence of cells.

View Article and Find Full Text PDF
Article Synopsis
  • Superhydrophobic surfaces with hierarchical micro/nanostructures, like the developed O-Ph-POSS on fluorinated graphene, achieve high water contact angles (152°) and low surface energy (5.6 mJ/m²), making them highly robust and effective in water-repelling applications.
  • The O-Ph-POSS-FG hybrid demonstrated remarkable oil absorption (200-500 wt%) and was successfully used to coat polyurethane sponges, achieving oil-water separation efficiencies of 90%-99%, even after multiple cycles.
  • Durability tests showed that the sponges maintained superhydrophobic properties over time, retaining effective water contact angles and separation efficiency after one year and multiple mechanical stress tests.
View Article and Find Full Text PDF

Development of Functional Biointerface Using Mixed Zwitterionic Silatranes.

Langmuir

November 2024

Department of Chemical & Materials Engineering, National Central University, Jhong-Li, Taoyuan 320, Taiwan.

Strategies to design multifunctional interfaces for biosensors have been extensively investigated to acquire optimal sensitivity, specificity, and accuracy. However, heterogeneous ingredients in clinical samples inevitably generate background signals, exposing challenges in biosensor performance. Polymer coating has been recognized as a crucial method to functionalize biointerfaces by providing tailored properties that are essential for interacting with biological systems.

View Article and Find Full Text PDF
Article Synopsis
  • - The study explores how different molecular structures of multialkylated aromatic amides (MAAs), used as drag reducing agents (DRAs) in natural gas pipelines, impact energy efficiency and corrosion inhibition.
  • - Researchers synthesized MAAs with varying numbers of amide groups and dodecane chains, finding that the molecular structure significantly influences the agents' interfacial activity and film-forming properties on carbon steel surfaces.
  • - Results showed that MAAs with more amide groups and dodecane chains led to thicker and smoother films, enhancing corrosion inhibition and drag reduction rates—specifically, MAA-3 exhibited the highest performance among the synthesized surfactants.
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!