N-Alkyl Perfluoroalkanamides as Low Molecular-Mass Organogelators
摘要:
A new class of low molecular-mass organogelators (LMOGs), N-alkyl perfluoroalkanamides, F(CF2)(n)CONH(CH2)(m)H, is described. The molecules are designed to exploit the incompatibilities of their three molecular parts, and the results demonstrate that this strategy can be used to tune molecular aggregation and gel stability. The gelating properties of these LMOGs have been examined in a wide variety of organic liquids (including alkanes, alcohols, toluene, n-perfluorooctane, CCl4, and DMSO) as a function of the N-alkyl and perfluoroalkyl chain lengths by X-ray diffraction, polarizing optical microscopy, infrared spectroscopy, differential scanning calorimetry, and small-angle neutron scattering (SANS). The gels are thermally reversible and require generally very low concentrations (<2 wt %) of LMOG. Several of the gels are stable for very long periods at room temperature. The incompatibility of the fluorocarbon and hydrocarbon segments causes the LMOGs to aggregate, probably into lamellae within the fibrils that constitute the basic unit of the gel networks. The SANS studies show that the cross-sections of fibers in the gel networks of LMOGs with shorter perfluoroalkyl chains are much larger than those with longer ones. Comparisons with the gelating properties of some analogous esters (F(CF2)(n)CO2(CH2)(m)H) and diblock perfluoroalkylalkanes (F(CF2)(n)(CH2)(m)H) indicate that additional ordering within the aggregate units is enforced by the intermolecular H bonding among amide groups that is evidenced by IR spectroscopy. Analyses of these results and structure/solvent correlations are provided.
PROBLEM
To provide an environmentally-friendly method for producing industrially an ester compound.
SOLUTION
The present invention is a method for producing an ester compound which comprises subjecting a carboxylic acid and an alcohol to dehydration-condensation reaction using an involatile acid catalyst and then removing the residual acid catalyst by bringing a weak basic substance into contact with the residual acid catalyst.
Structure and Thermal Behavior of Layered Silver Perfluorocarboxylates
作者:Seung Joon Lee、Sang Woo Han、Hyouk Jin Choi、Kwan Kim
DOI:10.1021/jp0255841
日期:2002.8.1
The structure and thermal behavior of silver perfluorocarboxylates (AgCO2(CF2)nCF3, n = 10, 12, 14, and 16) have been investigated by using various analytical tools. The X-ray diffraction patterns were composed of a series of peaks that could be indexed to (0k0) reflections of a layered structure. The adjacent layers were presumed to overlap by as much as 94% of the terminal CF3 groups. Diffuse reflectance
Perfluorocarbon-stabilized silver nanoparticles manufactured from layered silver carboxylates
作者:Seung Joon Lee、Sang Woo Han、Kwan Kim
DOI:10.1039/b111607j
日期:2002.2.27
Perfluorocarboxylate-stabilized silver nanoparticles have been prepared uniformly via the thermal decomposition of layered silver perfluorocarboxylates (AgCO2(CF2)nCF3, n = 10, 12, 14 and 16).
COMPOSITIONS, METHODS, AND SYSTEMS COMPRISING FLUOROUS-SOLUBLE POLYMERS
申请人:Swager Timothy M.
公开号:US20120177578A1
公开(公告)日:2012-07-12
The present invention generally relates to compositions, methods, and systems comprising polymers that are fluorous-soluble and/or organize at interfaces between a fluorous phase and a non-fluorous phase. In some embodiments, emulsions or films are provided comprising a polymer. The polymers, emulsions, and films can be used in many applications, including for determining, treating, and/or imaging a condition and/or disease in a subject. The polymer may also be incorporated into various optoelectronic device such as photovoltaic cells, organic light-emitting diodes, organic field effect transistors, or the like. In some embodiments, the polymers comprise pi-conjugated backbones, and in some cases, are highly emissive.