Katsuhisa Takishita

Recognition of hydrophilic amino and N,N-dimethylamino compounds by the self-assembled aggregates of fluoroalkylated end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer

Self-assembled aggregates of new fluoroalkylated end-capped N-(1,1-dimethyl-3-oxobutyl)acrylamide oligomer can recognize selectively hydrophilic amino and N,N-dimethylamino compounds such as methylene blue, methyl orange, acriflavine hydrochloride and 3-aminophenylboronic acid, and transfer these compounds from aqueous solutions to organic media; in contrast, these aggregates were not able to recognize hydrophilic compounds such as 4-hydroxyazobenzene-4′-sulfonic acid sodium salt, acridine hydrochloride, 4-methoxyphenylboronic acid, 4-methyl-3-nitrophenylboronic acid, and phenylboronic acid.

Synthesis and properties of novel perfluorocyclohexylated compounds with bis(perfluorocyclohexane carbonyl) peroxide

Bis(perfluorocyclohexane carbonyl) peroxide was prepared by the reaction of the corresponding acyl fluoride and hydrogen peroxide. This peroxide was applied to the preparation of perfluorocyclohexylated end-capped oligomers via a radical process under very mild conditions. In cyclic perfluorocyclohexylated end-capped oligomers containing hydroxy segments, these oligomers could cause a gelation in water and in polar organic solvents such as MeOH, EtOH, dimethylformamide (DMF), and dimethylsulfoxide (DMSO), and the gelling ability of these oligomers was superior to that of the corresponding linear perfluorooxaalkylated oligomers. Furthermore, perfluroocyclo-hexylation of polystyrene or benzene was proceeded via a single electron transfer reaction by using this peroxide.

Preparation and applications of a variety of fluoroalkyl end-capped oligomer/hydroxyapatite composites.

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.

Synthesis and applications of bis(perfluorodecalin-1-carbonyl) peroxide

Abstract New bis(perfluorodecalin-1-carbonyl) peroxide (PFDC-PO) was prepared by the reaction of hydrogen peroxide with perfluorodecalin-1-carbonyl chloride, obtained from the chlorination of the corresponding carboxylic acid and phosphorus oxychloride in the presence of DMF. A kinetic study showed that PFDC-PO decomposes homolytically with a three-bond fission. Heptadecafluorodecahydro-1-naphthyl (F-DECALYL) end-capped oligomers were prepared by the reaction of PFDC-PO with monomers such as acrylic acid (ACA), N , N -dimethylacrylamide (DMAA), 3-methacryloxy-2-hydroxypropyltrimethylammonium chloride, and N -(1,1-dimethyl-3-oxobutyl)acrylamide (DOBAA) via a radical process. Interestingly, these F-DECALYL end-capped oligomers obtained were soluble in water and common organic solvents, although parent perfluorodecalin is insoluble in water and common organic solvents except hexane. F-DECALYL end-capped ACA oligomer was easily soluble in water and reduced the surface tension of water effectively. Additionally, F-DECALYL end-capped ACA oligomer was found to enhance dramatically luminol chemiluminescence light yield compared to the corresponding linear fluoroalkylated ACA oligomer. F-DECALYL end-capped DMAA and DOBAA oligomers were insoluble in water; however, these oligomers were soluble in common organic solvents. Especially, F-DECALYL end-capped DOBAA oligomer was found to form a monomolecular film at the air–water interface.