Jun-Ting Zou, Yu-Song Wang, Wen-Min Pang, Lei Shi, Fei Lu
The formation process and composition of the acrylonitrile/urea inclusion compounds (AN/UIC) with different aging times and AN/urea molar feed ratios are studied by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). It is suggested that DSC could be one of the helpful methods to determine the guest/host ratio and the heat of decomposition. Meanwhile, the guest/host ratio and heat of deformation are obtained, which are 1.17 and 5361.53 J/mol, respectively. It is found that the formation of AN/UIC depends on the aging time. The formation process ends after enough aging time and the composition of AN/UIC becomes stable. It is suggested AN molecules included in urea canal lattice may be packed flat against each other. XRD results reveal that once AN molecules enter urea lattice, AN/UIC are formed, which possess the final structure. When AN molecules are sufficient, the content of AN/UIC increased as aging time prolonging until urea tunnels are saturated by AN.
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http://arxiv.org/abs/1210.2517
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