The Formation and Characteristics of Acrylonitrile/Urea Inclusion Compound

TL;DR

This study investigates the formation, structure, and composition of acrylonitrile/urea inclusion compounds using DSC and XRD, revealing how aging time influences their development and molecular packing.

Contribution

It provides new insights into the formation process, guest/host ratio, and structural characteristics of AN/UIC, highlighting the role of aging time and molecular packing.

Findings

DSC can determine guest/host ratio and heat of decomposition.

AN molecules are packed flat within urea canals.

Formation depends on aging time and saturation of urea tunnels.

Abstract

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 suggested AN molecules included in urea canal lattice may be packed flat against each other. It is found that the formation of AN/UIC depends on the aging time. 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 length of AN molecular arrays in urea canals increases as aging time prolonging until urea tunnels are saturated by AN.