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2-Furyloxirane(FO) with purity of over 99% was prepared in 80% yield by epoxidation of furfural with trimethylsulfonium chloride and potassium hydroxide in acetonitrile/water solution. Polymerization of FO was realized using tri-isobutyl aluminum (Al( i-Bu)) as catalyst, when Al( i-Bu) concentration was 0.009 mol/L, poly(2-furyloxirane)(PFO) with M of 3.4 kg/mol and a polydispersity index of 1.5 was obtained in yield of 88% after polymerization at 25 °C for 48 h. The corresponding PFO showed glass transition temperature ( T) of Ca. 1 °C and 5 wt% thermal decomposition temperature( T) of 260 °C. The obtained PFO was almost 100% head-to-tail structure, and it was a good plasticizer and thermal stabilizer for poly(propylene carbonate)(PPC), an alternate copolymer of propylene oxide and carbon dioxide. For PFO/PPC polyblend with PFO loading of 2 wt%, its T increased by 50 °C from 214 °C of pure PPC to 264 °C, while its elongation at break increased from 13% of pure PPC to 29%. [ABSTRACT FROM AUTHOR]

Crystallization kinetics of the Zr 70-x Ni 14+x Al 16 (x = 0, 5, 10, 15, and 20 at.%) metallic glasses (MGs) was investigated using the non-isothermal and isothermal methods, respectively. The crystallization of the Zr 70-x Ni 14+x Al 16 (x = 15 and 20 at.%) MGs proceeds by the nucleation and growth of Zr 2 Ni 3 Al 5 and Zr 6 NiAl 2 crystals. The crystallization sequence of the Zr 70-x Ni 14+x Al 16 (x = 0, 5, and 10 at.%) MGs can be concluded as follows: amorphous phase → amorphous phase + Zr 2 Ni 3 Al 5 + ZrNiAl crystals → Zr 6 NiAl 2 crystals. The crystallization kinetics of the initial and intermediate stages for the present system changes from the diffusion-controlled one-dimensional growth to two- and three-dimensional growth. Compared with the Zr 70-x Ni 14+x Al 16 (x = 15 and 20 at.%) MGs, the nucleation and growth during the initial crystallization of the Zr 70-x Ni 14+x Al 16 (x = 0, 5, and 10 at.%) MGs are relatively faster, which should be contributed to their lower activation energies for initial crystallization. The subsequent crystallization proceeds by a slower nucleation and growth compared with the Zr 70-x Ni 14+x Al 16 (x = 15 and 20 at.%) MGs, which should be suppressed by the endothermic phase transition from Zr 2 Ni 3 Al 5 and ZrNiAl crystals to Zr 6 NiAl 2 crystals. The present studies could give a complementary understanding on crystallization behaviors of metastable alloys. [ABSTRACT FROM AUTHOR]