Syntheses and magnetic properties of novel complexes of polymer containing bithiazole ring and salicylic acid

A novel polymer (SDP) was first synthesized from 2,2′-diamino-4, 4′-bithiazole (DABT) with salicylic acid and paraformaldehyde (PF). SDP–Fe2+ was prepared from SDP and FeSO4 in DMSO. SDP–Prussian blue was prepared from SDP–Fe2+ and potassium ferricyanide (K3[Fe(CN)6]) in DMSO. They were characterized through IR, 1H NMR, XPS and ESR. The magnetic behavior of two polymeric complexes was measured as a function of magnetic field strength (0–60 kOe) at 5 K and as a function of temperature (5–300 K). SDP–Prussian blue exhibits a hysteresis cycle at 5 K, the observed coercive field is Hc=40 Oe, and the remnant magnetization Mr=0.035 emu g−1. The result shows that SDP–Fe2+ is an antiferromagnet while SDP–Prussian blue is a ferromagnet.