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A benzodioxole derivative, 4-(2-(benzodioxol-5-yloxy)ethoxy)benzophenone (BPC2BDO), based on 4-hydroxybenzophenone and sesamol was synthesized, and used as a one-component Type II photoinitiator. The structure of BPC2BDO was characterized by elementary analysis, APCI-MS, (1)H NMR, and (13)C NMR. The rate of decomposition (R(d)) of BPC2BDO in acetonitrile was studied by UV-Vis spectroscopy and found that R(d) was proportional to light intensity. Real-time near-IR was used to study the kinetics of photopolymerization of the photoinitiator. As the benzophenone (BP) moiety and hydrogen donor were introduced into one molecule in BPC2BDO, radicals could be generated through intra-molecular reaction due to the close vicinity of the hydrogen donor and BP, which might be faster than inter-molecular reaction. The results also showed that the rate of polymerization of acrylates was significantly higher than that of methacrylates at the same polymerization conditions; the functionality of acrylates, concentration of BPC2BDO, and light intensity affected the polymerization rate and the final conversion.

Three-dimensional (3-D) needled C f /ZrC-SiC composites were successfully fabricated by polymer infiltration and pyrolysis combined with ZrC precursor impregnation. The microstructure and mechanical properties of the composites were studied using XRD, SEM and three-point bending test. The composite with PyC interphase between fiber and matrix had a bulk density of 2.20 g/cm 3 , an open porosity of 13%, and a bending force of 356 N, and exhibited a nonbrittle failure behavior due to propagation and deflection of cracks, and fracture and pullout of fibers. The mass lose and linear recession rate of the 3-D needled C f /SiC-ZrC composite during oxy-propane torch test were 0.010 g/s and 0.001 mm/s, respectively. The formation of ZrSiO 4 melt on the surface of the composite contributed mainly the excellent high-temperature property.

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