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Calcium chloride reacted with sodium carbonate in the presence of a variety of fluoroalkyl end-capped oligomers such as fluoroalkyl end-capped acrylic acid oligomer (RF-[ACA] n-RF), 2-methacryloyloxyethanesulfonic acid oligomer (RF-[MES] n-RF), N, N-dimethylacrylamide oligomer (RF-[DMAA] n-RF) and acryloylmorpholine oligomer (RF-[ACMO] n-RF) to afford the corresponding fluorinated oligomers/calcium carbonate composites. Each fluorinated oligomer/calcium carbonate composite thus obtained is nanometer size-controlled very fine particles (25-114 nm) possessing a good dispersibility and stability in a variety of solvents including water. Thermal stability of these fluorinated calcium carbonate nanocomposites was studied by thermogravimetic analyses measurements. Fluorinated oligomes, in which the theoretical oligomer content in the composites is 19%, were able to give no weight loss corresponding to the content of oligomer in each case even after calcination at 800 °C. On the other hand, a slight weight loss corresponding to the contents of oligomers in the composites after calcination at 800 °C was observed in RF-(MES) n-RF/, RF-(DMAA) n-RF/ and RF-(ACMO) n-RF/calcium carbonate nanocomposites, in which the theoretical contents of the oligomers were 36-53%, although RF-(ACA) n-RF/calcium carbonate nanocomposites gave a clear weight loss corresponding to the contents of oligomer under similar conditions. Fluorinated oligomers/calcium carbonate nanocomposites possessing no weight loss at 800 °C were applied to the surface modification of poly(methyl methacrylate) (PMMA) to exhibit a good oleophobicity imparted by fluorines on the surfaces. Interestingly, these fluorinated calcium carbonate nanocomposites after calcination at 800 °C were found to exhibit the similar oleophobic characteristic on the modified PMMA surfaces as well as that of the nanocomposites before calcination. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Novel fluoroalkyl end-capped oligomers/hydrogarnet (katoite) nanocomposites were prepared by the hydrothermal reactions of a stoichiometric mixture of Ca(OH)2, Al(OH)3, and Al2Si2O5(OH)4 in the presence of the corresponding fluorinated acrylic acid, acryloylmorpholine, and N,N-dimethylacrylamide oligomers. These fluorinated katoite nanocomposites thus obtained are nanometer sizecontrolled, and were found to exhibit a good dispersibility in water, methanol, ethanol, and tetrahydrofuran. Fluoroalkyl end-capped oligomers were also applied to the dispersion of parent katoite into these solvents; however, a poor dispersiblity for these solvents was observed. On the other hand, fluoroalkyl end-capped 2-methacryloyloxyethanesulfonic acid oligomer [RF-(MES)n-RF] was able to solubilize katoite into water to afford the transparent colorless solution. The obtained RF-(MES)n-RF/katoite nanocomposites were found to exhibit a good antibacterial activity against Staphylococcus aureus, and were also applied to the surface modification of poly(vinyl alcohol) to exhibit a good oleophobicity imparted by fluorine on the surface. [ABSTRACT FROM AUTHOR]

The article discusses a study on the nonflammable characteristic of fluoroalkyl end-capped oligomer in silica gel matrices. It says that Shodex DS-4 (pomp) and Shodex RI-71 (detector) gel permeation chromatography were used. It adds that silica nanocomposite reaction with fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl) acrylamide oligomer [RF-(DOBAA)n-RF] can afford the novel nanocavity with an extraordinarily high oxidation resistance.

Fluoroalkyl end-capped acrylic acid oligomer/silica nanocomposites were prepared by reaction of the corresponding oligomer with silica nanoparticles in the presence of alkaline silicate in water. Fluorinated oligomer/silica nanocomposites thus obtained are nanometer size-controlled fine particles (48-67 nm) and were found to exhibit a good dispersibility in their aqueous solutions, although the silica composites, which were prepared in the absence of oligomer, afforded submicrometer size-controlled particles (197 nm). These fluoroalkyl end-capped oligomer/silica nanocomposites were applied to the surface modification of aluminum plate. Interestingly, the modified plate surface exhibits a strong oleophobicity imparted by fluorine. On the other hand, this modified plate surface was found to exhibit a good hydrophilicity related to the presence of carboxyl groups in composites when the environment is changed from air to water on the surface. [ABSTRACT FROM AUTHOR]

A variety of fluoroalkyl end-capped oligomers/silver nanocomposites were prepared by the reactions of silver ions with poly(methylhydrosiloxane) in the presence of fluoroalkyl end-capped N, N-dimethylacrylamide oligomer, N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer, N, N-dimethylacrylamide cooligomer containing poly(dimethylsiloxane) segments in organic media such as toluene and 1,2- dichloroethane. These fluorinated oligomers/silver nanocomposites thus obtained were found to exhibit clear plasmon absorption bands around 420 nm related to the formation of silver nanoparticles. In particular, these composites could display narrow plasmon absorptions around 420 nm in toluene by the addition of trioctylamine (TOA). On the other hand, the corresponding non-fluorinated N-(1,1- dimethyl-3-oxobutyl)acrylamide oligomer was not able to afford such a plasmon absorption under similar conditions. These fluorinated oligomers/silver nanocomposites in organic media have been found to be stable for more than 10 days. Transmission electron microscopy (TEM) and dynamic light scattering (DLS) measurements showed that silver nanoparticles could be effectively encapsulated into fluorinated oligomeric aggregate cores to afford colloidal stable fluorinated oligomers/silver nanocomposites. Fluorinated oligomers/silver nanocomposites were also applied to the surface modification of traditional organic polymers such as polystyrene (PSt) and poly(methyl methacrylate) (PMMA) to exhibit not only a good oleophobicity imparted by fluorine but also a higher surface antibacterial activity related to the silver nanoparticles on their surface. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(VM) n -RF] underwent the sol–gel reaction under alkaline conditions in the presence of anatase titanium oxide nanoparticles (an-TiO2) in tetrahydrofuran to give the corresponding fluorinated oligomer/anatase titanium oxide nanocomposites [RF-(VM-SiO2) n -RF/an-TiO2]. Crystalline structure of an-TiO2 in the nanocomposites thus obtained was found to keep completely its structure without phase transformation to rutile even after calcination at 1000°C, although crystalline structure of the original an-TiO2 nanoparticles underwent a complete phase transformation to the rutile under similar conditions. Interestingly, RF-(VM-SiO2) n -RF/an-TiO2 nanocomposites before and after calcination at 1000°C exhibited the similar photocatalytic activity for the decolorization of methylene blue under UV light irradiation. [Copyright &y& Elsevier]