A series of bis(4‐thio‐1,8‐naphthalic anhydride)s and the corresponding bis(N‐amino naphthalimide) derivatives were synthesized from readily available compounds in high yield. A series of novel poly(thioether‐naphthalimide)s, which utilized hydrazine as the diamine, were synthesized by a one‐step polymerization reaction in m‐cresol. Poly(thioether‐naphthalimide)s with inherent viscosities of 0.57–1.73 dL/g were obtained. The polymers were soluble in CHCl3 and were determined to have high molecular weights by means of gel permeation chromatographic analysis. They were soluble in m‐cresol and could be cast into tough films from m‐cresol solution. The glass‐transition temperature (Tg) values of the polyimides ranged from 320 to 353 °C. Polyimides from the bisphenol dianhydride, derived from 9,9‐bis(4‐hydroxyphenyl)fluorene, did not show a clear transition in the DSC analysis. Degradation temperatures for 5% weight loss all occurred above 430 °C in nitrogen. The series of monomers were successfully copolymerized with each other. Monomers 6a and 7a, containing the bisphenol A moiety, could also be copolymerized with perylenetetracarboxylic dianhydride. These copolymers had high Tg's and were thermally stable. The UV–vis absorption properties of the polymers were also examined. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1040–1050, 2001

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Crystalline LaNi5 powder was synthesized by mechanical alloying of constituent metals preceding annealing at lower than a melting point of the alloy. The structure of the sample as mechanically alloyed was amorphous. After two-step heat treatments at 723 K in a stream of hydrogen and at 1273 K in helium, the crystalline sample was obtained. The hydrogen absorption characteristics of the crystalline sample were in fair agreement with those of the alloy prepared by a conventional melting technique.