Carbonated soybean oil (CSBO) can be used as intermediate for the synthesis of non-isocyanate polyurethanes (NIPUs). In this work, CSBO was prepared by the reaction of epoxidized soybean oil (ESBO) with carbon dioxide (CO 2 ) using a novel composite catalyst comprising SnCl 4 Á 5H 2 O and tetrabutylammonium bromide (TBABr). The evolution of the reaction process and structure of CSBO were studied by means of IR, 1 H-NMR, and GPC techniques. Effects of catalyst formulation and various reaction conditions on the reaction were examined. The results showed that the obvious improvement in ESBO conversion using the present composite catalyst under mild conditions was achieved. Moreover, it was interesting to note that very high purity of CSBO was not a prerequisite for the synthesis of NIPUs with good performance.

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By the conventional mixed oxide method (1Àx)Bi(Mg 1/2 Ti 1/2 ) O 3 -xBaTiO 3 ((1Àx)BMT-xBT, x = 0.2À1.0) ceramics were prepared. For x 0.4, a bismuth-rich phase was observed beside the perovskite phase. For 0.5x 0.92 ceramics, all the compositions belong to the pseudocubic phase, while the tetragonal phases were formed when x ! 0.94. With the increase of BT content, a change from a relaxor-like behavior to a normal ferroelectric behavior was observed, while the change of T max is in the form of "U" curve. Furthermore, stable dielectric permittivity (1500-3000) and low losses (tan d < 2%) were obtained in the 0.4x 0.6 ceramics in the temperature range 200°C-400°C, indicating a potential for high-temperature applications.

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