Eiichi Shouji

Synthesis of polyphenylene thioethers through cationic oxidative polymerization

Abstract Polyaromatic sulfides are efficiently and conveniently prepared by cationic oxidative polymerization. Diphenyl disulfides are quantitatively polymerized to yield poly(p-phenylene sulfide)s as white powders whose structure predominately contains 1,4-phenylene sul-fide bonds. The disulfides are oxidized to phenylbis(phenylthio) sulfonium cations as active species of the polymerization. Repeating the oxidation and electrophilic reaction of the cation to the p-position of disulfides yields the polymer.

Electrophilic Reaction of Phenyl Bis(Phenylthio) Sulfonium Cation as an Active Species for the Oxidative Polymerization of Diphenyl Disulfide

Computer modeling predicts that the methyl bis(methylthio) sulfonium cation can act as an efficient electrophile for sulfide bond formation in which the sulfur atoms at the side position of the cation react with the phenyl ring of an aromatic molecule. The electrophilic reaction mechanism of phenyl bis-(phenylthio) sulfonium cation with anisole was examined using computer simulation. The reaction between phenyl bis- (phenylthio) sulfonium cation, which is a homogeneous structure of thecation, and anisole shows the efficient formation of 4-phenylthioanisole with diphenyl disulfide as a by-product. In the oxidative polymerization of diphenyl disulfide, the formation process of polyp-phenylene sulfide) includes an elementary reaction between the phenylthio group at each side position of the phenyl bis(phenylthio) sulfonium cation and the carbon at the para position of the phenyl ring.

PHOTOCHEMICAL RECYCLING OF POLYARYLENE SULFIDE

The selective degradation of polyarylene sulfide via soluble polysulfonium salts was employed to give the monomer.

Fluorescence behavior of porphinato zinc derivative in the molecular assembly of polymerized lipid

Summary3,8,13,17-Tetramethyl-7,12-dicarboxy-2,18-bis(octadecyloxycarbonylethyl) porphinato zinc (DCPZn) was incorporated into bilayer membrane of liposomes of 1,2-bis(2,4-octadecadienoyl)sn-glycero-3-phosphocholine (DODPC). The liposomes were polymerized by initiators like water-insoluble azobisisobutyronitrile (AIBN) or/and water-soluble azobis(amidinopropane) dihydrochloride (AAPD). DCPZn does not disturb the molecular packing of DODPC in the bilayer and after the polymerization, DCPZn is fixed monomolecularly in the network of the crosslinked bilayer membrane, while in the monomeric bilayers the dispersion state of DCPZn depends on temperature and concentration.

Diene-containing 1,3-diacylglycero-2-phosphoric acid

SummaryA polymerizable 1,3-diacylglycero-2-phosphoric acid, 1,3-bis(octadeca-trans-2, trans-4-dienoyl)-rac-glycero-2-phosphoric acid 1, was synthesized. The lipid bilayer formation and its pH-dependence were elucidated by ultraviolet, fluorescence, DSC and 1H- and 31P-NMR measurements. The rate of photopolymerization as bilayer assemblies was sensitive to pH, i.e. the the degree of dissociation of the phosphoric group of 1.