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Abstract: Two novel poly(Schiff base)s (PPHBT and PPHPHN) were prepared by polycondensation of 2,2′-diamino-4,4′-bithiazole (DABT), 5,6-diamino-1,10-phenanthroline (DAPH) with bisdecyloxyterephthaldehyde (BDTA), respectively. The structures of the poly(Schiff base)s were determined by IR and 1H NMR spectroscopy. The Nd3+ complexes of poly(Schiff base) were prepared and characterized. The contents of Nd for complexes were measured by complexometric titration. The magnetic behavior of the complexes was examined as a function of magnetic field strength at 4K and as a function of temperature (4–300K). The results show that both PPHBT-Nd3+ and PPHPHN-Nd3+ exhibit the characteristic of soft-magnetic materials at low temperature. [Copyright &y& Elsevier]

Abstract: Two novel fully conjugated polymers containing bithiazole rings (PDDBTz and PDABTz) were first synthesized by polycondensation of 2,7-dimethyl-2,4,6-octatriene-1,8-dial with 2,2′-bis(diethylphosphinatyl methyl)-4,4′-bithizole or 2,2′-diamino-4,4′-bithiazole (DABT). The structure of the polymers was determined by IR, 1H NMR and elemental analysis. PDDBTz is soluble in trifluoroacetic acid and DMSO, whereas PDABTz is soluble in common solvent such as THF, DMSO, DMF. Bithiazole rings were introduced to provide bidentate N-donor sites for binding metal ions. Their lanthanide metal complexes were prepared. The magnetic behavior of these polymeric complexes was measured as a function of magnetic field strength (0–60kOe) at 4K and as a function of temperature (4–300K) at magnetic field strength of 30kOe. The results show that they all exhibit features of soft ferromagnet. [Copyright &y& Elsevier]

A series of novel polyimide and poly(Schiff base) oligomers containing substituted bithiazole rings were designed and synthesized, for the first time, by polycondensation of 5,5′-dimethyl-2,2′- diamino-4,4′-bithiazole (MDABT) with dianhydrides (pyromellitic dianhydride, 3,3′-4,4′-benzophenone tetracarboxylic dianhydride and bis (3,4-dicarboxyphenyl) ether dianhydride), and dialdehydes (oxalic aldehyde, isophthalaldehyde and terephthalaldehyde). The structure of the oligomers was determined by IR and 1H NMR spectroscopy, and elemental analysis. The oligomers showed good thermal stability. The Fe2+ complex of poly(Schiff base), synthesized from MDABT with oxalic aldehyde (PMTOA), was prepared with 13.7% Fe content and found to be a ferromagnet at low temperature. [Copyright &y& Elsevier]

The preparation and magnetism of two rare earth polymeric complexes, PDTEN-Nd3+ and PMDTEN-Nd3+, which are obtained by polycondensation of -diamino--bithiazole (DABT) or -dimethyl--diamino--bithiazole (MDABT) with glyoxal and complexation of Nd3+ are described. New magnetic phenomena of temperature dependence and applied external field dependence of magnetization of the two complexes are observed in an applied field of 20 kOe and at . With temperature increasing, magnetization decreases to be negative above transition temperature, at which the magnetic state converts from ferromagnetism to diamagnetism. With applied field increasing, magnetization increases first then declines from maximum over turning point. These do not follow the behaviors expected of conventional ferromagnets. [Copyright &y& Elsevier]

Two polymeric ferro-complexes were first synthesized from FeSO4·7H2O and poly(Schiff base)s. The poly(Schiff base)s were prepared by polycondensation of 5,5′-dimethyl-2,2′-diamino-4,4′-bithiazole (MDABT) with oxalic aldehyde and isophthalaldehyde, respectively. The structures of polymers and complexes were characterized by IR and 1H NMR spectra. The Fe contents of complexes were measured by X-ray spectrometer. The magnetic behavior of the complexes was examined as a function of magnetic field strength at 4 K and as a function of temperature (4–300 K). The results show that PMTOA-Fe2+ is a soft ferromagnet while PMTIA-Fe2+ exhibits features of an antiferromagnet. [Copyright &y& Elsevier]

This paper describes the synthesis of a novel heterocyclic polymer incorporating both bithiazole and tetrathiapentalene moieties in the main chain. The complexion of the polymer with FeSO4 or NdCl3 in dimethyl sulfoxide produced corresponding metal complexes. Based on IR spectra and X-ray photoelectron spectroscopy (XPS) data the structure of these metal complexes is discussed briefly. The magnetic properties of the metallopolymers were measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K) under an applied magnetic field of 30 kOe, respectively. The neodymium complex exhibits a hysteresis cycle at 5 K, the observed coercivity Hc and the remnant magnetization Mr are 15 Oe and 0.00035 emu/g, respectively. [Copyright &y& Elsevier]