Calcium chloride reacted with sodium carbonate in the presence of a variety of self-assembled molecular aggregates formed
by fluoroalkyl end-capped acrylic acid, 2-methacryloyloxyethane sulfonic acid, dimethylacrylamide, and acryloylmorpholine
oligomers in aqueous solutions to afford the corresponding fluorinated oligomers/calcium carbonate composites in excellent
to moderate isolated yields. These fluorinated calcium carbonate composites thus obtained were shown to have a good dispersibility
not only in water but also in traditional organic media including fluorinated solvents. Dynamic light scattering measurements
(DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that these fluorinated composites
are nanometer-size-controlled particles and well dispersed in these media. Cross-linked fluoroalkyl end-capped acrylic acid
co-oligomer containing poly(oxyethylene) units was also applied to the preparation of new cross-linked fluorinated calcium
carbonate nanocomposites under similar conditions. The obtained cross-linked fluorinated calcium carbonate nanocomposites
were found to have an extremely higher dispersibility in aqueous and organic media including fluorinated solvents, compared
to that of the corresponding fluoroalkyl end-capped oligomer nanocomposites. In particular, it was verified that these fluorinated
calcium carbonate nanocomposites are applicable to the dispersion above poly(methyl methacrylate) (PMMA) film surface. Interestingly,
field-emission SEM (FE-SEM) images of the cross-section of the modified PMMA films showed that calcium carbonate particles
dispersed into these PMMA films could be arranged regularly above the modified film surface. More interestingly, cross-linked
fluorinated oligomeric aggregates were able to provide suitable host moieties for the crystallization of calcium carbonate. 相似文献
Fluoroalkyl end‐capped cooligomers that contain both oxime‐blocked isocyanato and hydroxyadamantyl segments are prepared by the cooligomerization of fluoroalkanoyl peroxide with the corresponding monomers under mild conditions. This fluorinated cooligomer affords new cross‐linked fluoroalkyl end‐capped cooligomeric nanoparticles that contain adamantane segments by the deprotecting reaction of oxime‐blocked isocyanato segments in cooligomers in excellent to moderate isolated yield. A variety of cross‐linked fluoroalkyl end‐capped cooligomeric nanoparticles that contain adamantane segments are also prepared by similar deprotecting reactions with this fluorinated cooligomer in the presence of adamantane‐1,5‐diol. Furthermore, we have prepared cross‐linked fluoroalkyl end‐capped cooligomers that contain oxime‐blocked isocyanato segments by the use of 2‐hydroxyethyl acrylate and poly(ethylene glycol)‐containing methacrylate monomer as comonomers, respectively. However, the deprotecting reactions of the oxime‐blocked isocyanato segments in the cooligomers do not afford the expected nanoparticles, and these cross‐linked cooligomers are found to show a gelling characteristic. The thermal stability of these cross‐linked fluorinated cooligomeric nanoparticles that contain adamantane segments increases significantly compared to that of the parent fluorinated cooligomer. More interestingly, the thermal stability of these cross‐linked fluorinated nanoparticles is almost the same as that of the fluoroalkyl end‐capped acrylic acid oligomer/SiO2 nanocomposites (content of SiO2 in composites: 70%). In addition, these cross‐linked fluorinated nanoparticles have been applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate) to exhibit a good oleophobicity imparted by fluorine on their surface.
Amphiphilic fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide-acryloylmorpholine cooligomer/fluorescein nanocomposites afforded brilliant yellow-colored solutions in not only protic solvents such as methanol and ethanol but also protic-like solvents such as dichloromethane and 1,2-dichloroethane, respectively. However, the corresponding non-fluorinated cooligomer/fluorescein composites and parent fluorescein gave the colorless solutions under similar conditions. On the other hand, unexpectedly, such brilliant yellow-colored solutions provided by these fluorinated nanocomposites completely disappeared in aprotic solvents such as N,N-dimethylformamide, dimethyl sulfoxide, and tetrahydrofuran. Thus, these fluorinated fluorescein nanocomposites can exhibit a coloring-decoloring behavior through solvatochromic response. 相似文献
A variety of fluoroalkyl end-capped oligomers were applied to the preparation of fluorinated oligomer/hydroxyapatite (HAp) composites (particle size: 38-356 nm), which exhibit a good dispersibility in water and traditional organic solvents. These fluoroalkyl end-capped oligomer/HAp composites were easily prepared by the reactions of disodium hydrogen phosphate and calcium chloride in the presence of self-assembled molecular aggregates formed by fluoroalkyl end-capped oligomers in aqueous solutions. In these fluorinated HAp composites thus obtained, fluoroalkyl end-capped acrylic acid oligomers and 2-methacryloyloxyethanesulfonic acid oligomer/HAp nanocomposites afforded transparent colorless solutions toward water; however, fluoroalkyl end-capped N,N-dimethylacrylamide oligomer and acryloylmorpholine oligomer were found to afford transparent colorless solutions with trace amounts of white-colored HAp precipitants under similar conditions. HAp could be encapsulated more effectively into fluorinated 2-methacryloyloxyethanesulfonic acid oligomeric aggregate cores to afford colloidal stable fluorinated oligomer/HAp composites, compared to that of fluorinated acrylic acid oligomers. These fluorinated oligomer/HAp composites were applied to the surface modification of glass and PVA to exhibit a good oleophobicity imparted by fluorine. HAp formation was newly observed on the modified polyethylene terephthalate film surface treated with fluorinated 2-methacryloyloxyethanesulfonic acid oligomers and acrylic acid oligomer/HAp composites by soaking these films into the simulated body fluid. 相似文献
Cross-linked fluoroalkyl end-capped acrylic acid cooligomer containing poly(oxyethylene) units can form the nanometer size-controlled fine particles in aqueous solutions, and these cross-linked nanoparticles interact with cytochrome c (Cyto-c) to afford the corresponding cooligomeric nanoparticles–encapsulated Cyto-c effectively. Interestingly, we can easily isolate the fluorinated nanoparticles–encapsulated Cyto-c powder by the simple centrifugal separation of the corresponding aqueous solutions. The cross-linked fluorinated cooligomer also enables an effective transfer of Cyto-c from aqueous solution to ionic liquids such as 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide to afford the immobilized Cyto-c with the corresponding fluorinated cooligomer in quantitatively immobilized ratio (~100%). The immobilized Cyto-c exhibited a good dispersibility in the parent ionic liquid to afford the nanometer size-controlled fluorinated particles–encapsulated Cyto-c. Similarly, the cross-linked fluorinated cooligomer in ionic liquids such as 3-methylpyrazolium tetrafluoroborate (3MP-BF4) interacted with Cyto-c to afford the corresponding nanoparticles–encapsulated Cyto-c in quantitatively encapsulated ratio (~100%). These cross-linked fluorinated nanoparticles–encapsulated Cyto-c in water and ionic liquids were applied to the oxidation of guaiacol with hydrogen peroxide, and an extremely higher catalytic activity for this oxidation was observed in the ionic liquid (3MP-BF4). 相似文献
Fluoroalkanoyl peroxide reacted with 1,3,5,7-tetravinyl-1,3,5,7-tetramethylcyclotetrasiloxane (TTRV-Si) to afford fluoroalkyl end-capped oligomers containing some unreacted vinyl segments under very mild conditions. Fluoroalkyl end-capped cyclosiloxane oligomers containing some vinyl segments thus obtained reacted with N,N-dimethylacrylamide and fluoroalkanoyl peroxide to afford new fluorinated dendrimer-type block copolymers in good isolated yield. Similar reactions were also occurred by the use of 1,3,5-trivinyl-1,3,5-trimethylcyclotrisiloxane instead of TTRV-Si, and the corresponding fluorinated dendrimer-type block copolymer was obtained in good isolated yield. These fluorinated dendrimer-type block copolymers had an excellent solubility not only in water but also in traditional organic solvents including aliphatic fluorinated solvents. Interestingly, these fluorinated block copolymers were found to form the self-assembled dendrimer-type polymeric aggregates in aqueous solutions. More interestingly, these fluorinated block copolymers had an extremely higher dispersion ability of not only single-walled carbon nanotube and fullerenes but also magnetic nanoparticles into water, compared to that of the corresponding two fluoroalkyl end-capped oligomers. 相似文献
Fluoroalkyl end-capped oligomers reacted with tetraethoxysilane and silica/nanoparticles under alkaline conditions to afford
fluoroalkyl end-capped oligomers/silica nanoparticles (mean diameters: 31–54 nm) with a good dispersibility and stability
in organic media. Interestingly, the isolated fluorinated particle powders were found to afford nanometer size-controlled
colloidal particles with a good redispersibility and stability in these media. In addition, fluoroalkyl end-capped oligomers/silica
nanoparticles-encapsulated guest molecules such as stable organic radicals and ionic liquids were prepared under similar conditions.
These fluorinated nanoparticles-encapsulated guest molecules were applied to a new type of surface-modification agent, and
these particles were able to disperse well above the poly (methyl methacrylate) films. 相似文献
A variety of fluoroalkyl end-capped oligomers were prepared under mild conditions by the use of fluoroalkanoyl peroxide as a key intermediate. These oligomers can form the self-assembled molecular aggregates with the aggregations of end-capped fluoroalkyl groups in aqueous and organic media. Fluorinated self-assembled molecular aggregates containing carboxyl and sulfo groups were suggested to interact with positively charged HIV-1 to exhibit a potent anti-HIV-1 activity in vitro. In contrast, fluoroalkyl end-capped oligomers containing cationic segments exhibited not only the unique surface active properties imparted by fluorine as well as the usual low-molecular fluorinated surfactants, but also high surface antibacterial activity. Fluoroalkyl end-capped oligomers containing betaine-type segments were found to cause a gelation where the strong aggregation of the end-capped fluoroalkyl groups is involved in establishing the physical gel network in water and polar organic solvents under non-crosslinked conditions. Similarly, fluoroalkyl end-capped oligomers containing hydroxyl groups could cause a gelation, where the aggregation of fluoroalkyl groups and hydrogen-bonding interaction is involved in establishing a physical gel network in water and polar organic solvents under non-crosslinked conditions. Fluoroalkanoyl peroxide is also a convenient tool for the preparation of new fluoroalkyl end-capped oligomers containing recognition moieties such as diacetone segments. These fluorinated oligomers containing recognition moieties could form the self-assembled molecular aggregates to recognize selectively the hydrophilic amino and N,N-dimethylamino compounds as guest molecules. 相似文献
New fluoroalkyl end-capped 2-acrylamido-2-methylpropanesulfonic acid oligomers/clay composites were prepared by reaction of fluoroalkanoyl peroxide with the corresponding monomer in the presence of clay in aqueous solutions. These obtained fluorinated composites were nanometer size-controlled and were found to exhibit a good dispersibility in water and polar organic solvents such as methanol. The contents of clay in these nanocomposites were estimated to be 3~19% by the thermogravimetric analysis measurements. X-ray diffraction spectra showed the successful intercalation of fluorinated oligomers into the interlayer spaces of clay. These fluorinated clay nanocomposites were applied to the surface modification of poly(vinyl alcohol). In addition, these fluorinated nanocomposites were found to interact with methylene blue effectively to afford the fluorinated oligomers/clay/methylene blue nanocomposites. 相似文献
Cross-linked fluoroalkyl end-capped cooligomers possessing double decker-type aromatic silsesquioxane segments as core units
[RF-(Ar-SiSQ)x-(Co-M)y-RF] were prepared under mild conditions by the cooligomerizations of fluoroalkanoyl peroxide with the corresponding aromatic
silsesquioxane possessing bifunctional vinyl groups (Ar-SiSQ) and comonomers (Co-M) such as acryloylmorpholine (ACMO), N,N-dimethylacrylamide (DMAA) and N-(1,1-dimethyl-3-oxobutyl)acrylamide (DOBAA). Interestingly, these cross-linked fluorinated cooligomers thus obtained were
found to form the nanometer size-controlled nanoparticles with a good dispersibility in a variety of solvents including fluorinated
aliphatic solvents. These fluorinated cooligomeric nanoparticles were demonstrated to have red-shifted fluorescent emissions
related to the presence of aromatic silsesquioxane segments, compared with that of parent aromatic silsesquioxane, indicating
that each aromatic moiety in these nanoparticles can interact effectively with each other through the π–π stacking between
the aromatic moieties to afford the red-shifted fluorescent emissions. These fluorinated nanoparticles were also applied to
the surface modification of poly(methyl methacrylate) (PMMA) to exhibit not only a good oleophobicity imparted by fluorine
but also a fluorescent emission behavior related to aromatic silsesquioxane segments in nanoparticles on the modified PMMA
surface. More interestingly, cross-linked RF-(Ar-SiSQ)x-(DOBAA)y-RF cooligomeric nanoparticles interacted with fluorescein to give the corresponding fluorinated cooligomeric particles/fluorescein
nanocomposites in methanol. These fluorinated fluorescein nanocomposites were found to afford an extraordinarily enhanced
light absorption (λmax = 441 nm), compared with that of fluoroalkyl end-capped DOBAA oligomer [RF-(DOBAA)n-RF] possessing no aromatic silsesquioxane segments. 相似文献
Fluoroalkyl end-capped vinylphosphonic acid cooligomers-encapsulated magnetite nanocomposites were prepared by the magnetization of aqueous ferric and ferrous ions in the presence of the corresponding fluorinated cooligomers and magnetic nanoparticles under alkaline conditions. These fluorinated cooligomers magnetic composites are nanometer size-controlled very fine particles and have a good dispersibility and stability in water and traditional organic solvents. These fluorinated nanocomposites were also applied to the surface modification of poly(methyl methacrylate) to exhibit a good oleophobicity imparted by fluorine on their surface. Fluoroalkyl end-capped 2-methacryloyloxyethanesulfonic acid oligomer-encapsulated magnetite nanocomposites and fluoroalkyl end-capped 2-acrylamide-2-methylpropanesulfonic acid oligomer-encapsulated magnetite nanocomposites were prepared in good isolated yields by the magnetization of iron chlorides in the presence of the corresponding oligomers and magnetic nanoparticles under similar conditions. Colloidal stability of these fluorinated nanocomposites thus obtained in water was demonstrated to become extremely higher than that of fluorinated vinylphosphonic acid cooligomers/magnetic nanocomposites. 相似文献
Fluoroalkyl end-capped acrylic acid and sulfonic acid cooligomers reacted with tetraethoxysilane (TEOS) and silica/nanoparticles under alkaline conditions to afford the corresponding cooligomers/silica nanoparticles (mean diameters: 32-173 nm) with a good dispersibility and stability in aqueous and organic media. Interestingly, fluorinated nanoparticles containing carboxy groups were found to exhibit a potent and selective anti-HIV-1 activity in vitro. In contrast, fluorinated cooligomers containing sulfo groups were shown to have a potent and selective anti-SIVmac activity in vitro. 相似文献
Fluoroalkyl end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer [RF-(DOBAA)n-RF] reacted with hibitane in methanol at 90 °C to afford RF-(DOBAA)n-RF oligomeric nanoparticles-encapsulated hibitane in good isolated yields. These fluorinated oligomeric particles-encapsulated hibitane were nanometer size-controlled very fine particles, and were found to exhibit a good dispersibility and stability in a wide variety of traditional organic solvents including fluorinated aliphatic solvents. Each dispersed solution with fluorinated nanoparticles afforded transparent colorless solution. These fluorinated nanoparticles were also found to exhibit a good antibacterial activity, and were applied to the surface modification of traditional organic polymers such as poly(methyl methacrylate). 相似文献
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. 相似文献
Fluoroalkyl end-capped cooligomers having adamantane as a pendant group [RF-(Ad-HAc)x–(Co-M)y-RF] were prepared by the reactions of fluoroalkanoyl peroxide with 3-hydroxy-1-adamantylacrylate (Ad-HAc) and comonomers (Co-M)
such as acrylic acid (ACA), N,N-dimethylacrylamide (DMAA), and acryloylmorpholine (ACMO) under mild conditions. Thermogravimetric analyses (TGA) showed that
thermal stability of RF-(Ad-HAc)x–(Co-M)y-RF was superior to that of the corresponding fluoroalkyl end-capped cooligomers having adamantane in the main chains [RF-(Ad)x–(Co-M)y-RF] and the fluoroalkyl end-capped homooligomers possessing no adamantyl segments [RF-(M)n-RF]. It is interesting to note that fluoroalkyl end-capped Ad-Hac–DMAA cooligomer [RF-(Ad-HAc)x–(DMAA)y-RF] was found to form the nanometer size-controlled cooligomeric aggregates which consist of around 16 fluorinated cooligomeric
molecules in methanol/water mixed solvents. Furthermore, these fluorinated cooligomeric aggregate could occupy around 320
ADMDD [5-(2-adamantylidene)-2,2-dimethyl-1,3-dioxane-4,6-dione] molecules as guest molecules per aggregate core, although
ADMDD could not be encapsulated into the RF-(Ad)x–(Co-M)y-RF cooligomeric and RF-(M)n-RF homooligomeric aggregate cores under similar conditions. 相似文献
Radical addition of 2-benzoxypentafluoropropene [CF2C(CF3)OCOC6H5] (BPFP) with alcohols such as ethanol and 2-propanol was investigated to afford fluorinated alcohols. Radical addition of BPFP with cyclic ethers such as tetrahydrofuran, 1,3-dioxolane and tetrahydropyran was also achieved to afford addition products followed by hydrolysis to yield fluorinated alcohols possessing cyclic structures. Novel fluoroalkyl acrylates and methacrylates were synthesized from the fluorinated alcohols with (meth)acryloyl chlorides. Radical polymerization of the fluoroalkyl (meth)acrylates yielded polymers of 1.2 × 105 as the highest molecular weight. 相似文献