The ring-opening polymerization of 1,4-dioxan-2-one (PDO) was carried out by lanthanum tris(2,6-di-tert-butyl-4-methylphenolate) (La(OAr)3) as novel single component initiator. The influences of polymerization reaction temperature and the molar ratio of monomer to initiator on the monomer conversion and molecular weight of poly(1,4-dioxan-2-one) (PPDO) were explored. PPDO with high viscosity average molecular weight of 1.95×105 can be prepared at 40℃when [PDO]/ [La(OAr)3] molar ratio was 800. Mechanism investigation shows that the polymerization proceeds through a "coordinationinsertion" mechanism with selective rupture of acyl-oxygen bond of PDO.
A new polyamide containing bithiazole moieties (PTA) was synthesized by the polycondensation of 2, 2′-diamino-4, 4′-bithiazole (DABT) and oxalyl chloride. The polymer complex was prepared from PTA and NdCl3 in DMSO. They were characterized through IR and elemental analysis. The preliminary magnetic properties of the complex PTA-Nd3+ was investigated, it was found that the material is a ferromagnet at low temperature.
A series of polymeric complexes were prepared from Fe^(2+),Co^(2+) or Ni^(2+) and poly(Schiff base)(DAPcIPA), which was obtained by polycondensation of 5,6-diamino-1,10-phenanthroline(DAP)with isophthalaldehyde(IPA).The structures of the polymer and the polymeric complexes were characterized by IR,~1H-NMR and elemental analysis.The magnetic behavior of these complexes was measured as a function of magnetic field strength(0-3.98×10~6 A/m)at 5 K and as a function of temperature(5-300 K)at a magnetic field strength of 2.39×10~6 A/m.Experimental results show that DAPcIPA-Ni^(2+),DAPcIPA-Co^(2+) are soft ferromagnets while DAPcIPA-Fe^(2+) exhibits features of an antiferromagnet.
