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961.
Mari Inoki Fumihiko Akutsu Yasuyuki Kitayama Koichi Shinoda Yoshio Kasashima Kiyoshi Naruchi 《Macromolecular rapid communications》1996,17(11):805-811
Thermal reactions of alkali salts of 4-(1-bromoethyl)benzoic acid in bulk were investigated. These reactions were found to produce unexpectedly the graft copolymer, poly(4-vinylbenzoate)-graft-oligo(oxycarbonyl-1,4-phenylenethylidene) ( 1 ). The relative reactivity of the oligocondensation as well as the vinyl polymerization of the salts decreased in the following order: K > Na > Li. The reaction polymerization rate proceeded rapidly during the initial 15 min, and then slowed down. 相似文献
962.
Yasuyuki Yamada Hiroaki Nakajima Chisa Kobayashi Yoshiaki Shuku Kunio Awaga Shigehisa Akine Kentaro Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2023,29(1):e202203272
A C4h symmetrically substituted phthalocyanine, 1,8,15,22-tertrakis(2,4-dimethylpent-3-oxy)phthalocyanine (H2TdMPPc), was used to synthesize Tb3+-phthalocyanine double-decker complexes ([Tb(TdMPPc)2]s). Because H2TdMPPc has C4h symmetry, S,S, R,R, and meso isomers of [Tb(TdMPPc)2] were obtained depending on the difference in the direction of the coordination plane of two C4h-type phthalocyanines with respect to a central Tb3+ ion. We investigated the physical properties of these [Tb(TdMPPc)2] isomers, including their single-ion magnetic properties, and found that the spin-reversal energy barrier (Ueff) of the meso isomer was apparently higher than that of the enantiomers. Detailed crystal structural analyses indicated that the meso isomer has a more symmetrical structure than do the enantiomers, thereby suggesting that the higher Ueff of the meso isomer originated from the more highly symmetrical structure. 相似文献
963.
A novel methodology (electrostatic self‐assembly and covalent fixation) has been proposed for designing unusual polymer topologies such as star polymers, polymacromonomers, dumbbell‐shaped polymers as well as model network polymers. Thus new telechelic polymers having moderately strained cyclic onium salt group as single or both end groups were prepared and subjected to an ion‐exchange reaction to introduce multifunctional carboxylate anions as a counter‐anion. The electrostatically self‐assembled products were then subjected, either directly or after subsequent manipulation, to heat treatment to convert the ionic interaction into the covalent linkage by the ring‐opening reaction to produce a variety of topologically unique polymer architectures in high yields. 相似文献