Search results for "solubility parameters"
showing 3 items of 3 documents
Gelation and gel properties of two- and three-component pyrene based low molecular weight organogelators
2011
The research described in this thesis covers the synthesis, characterization and the study of the gelation ability of fteen pyrene based low molecular weight organogelators (LMOGs). The gelation and gel properties were investigated by rheometry, scanning electron microscopy, di erential scanning calorimetry, UV-Vis and uorescence spectroscopy. The pyrene based LMOGs form complexes with 2,4,7-trinitro uorenone (TNF) and self-assemble non-covalently through - stacking, donor-acceptor and van der Waals interactions to form thermoreversible gels, which remain stable at least for two years. The strongest gels were obtained in primary alcohols whereas the poor solubility of TNF restricted gelatio…
Molecular Features Behind Formation of α or β Co-Crystalline and Nanoporous-Crystalline Phases of PPO
2022
Guest molecular features determining the formation of α and β phases of poly(2-6-dimethyl-1,4-phenylene) oxide (PPO) are explored by collecting literature data and adding many new film preparations, both by solution casting and by guest sorption in amorphous films. Independently of the considered preparation method, the α-form is favored by the hydrophobic and bulky guest molecules, while the hydrophilic and small guest molecules favor the β-form. Furthermore, molecular modeling studies indicate that the β-form inducer guests establish stronger dispersive interactions with the PPO units than the α-form inducer guests. Thus, the achievement of co-crystalline (and derived nanoporous crystalli…
Effect of Polarity of Solvent on Silanization of Halloysite Nanoclay Using (3-Glycidyloxy propyl) Trimethoxy Silane
2021
Abstract: The grafting of silane groups on clay surfaces has been recently investigated in order to fabricate versatile compounds with new potential applications in materials science and ecological engineering. This work explored the influence of variety of solvents with variable polarity on the silanization of halloysite nanoclay (HNT) surface by (3-Glycidyloxy propyl) trimethoxy silane. To this purpose, the functionalization of HNT by 3-Glycidyloxypropyltrimethoxysilane (GOPTMS) has been conducted in Ethanol (polar protic solvent), Tetrahydrofuran (THF) and Acetonitrile (polar aprotic solvents), and Hexane, 1,4-Dioxane and Toluene (non polar solvents). The silane grafted materials were ch…