Investigation of Thermal Properties and Growth Mechanisms of Nano-Porous Calix[4]arenes

p-tert-Butylcalix[4]arene (PC4), de-tert-butyl calix[4]arene (DC4) and sulfonated calix[4]arene (SC4) were synthesized by means of acetalization, dealkylation and sulfonation. Their structures and morphologies were characterized with fourier transform infrared spectrometry (FTIR), nuclear magnetic resonance spectroscopy (NMR) and scanning electron microscopy (SEM). The thermal properties of three calix[4]arenes were investigated with thermogravimetric analysis (TGA) and differential thermal gravity (DTG). TGA and DTG curves of calixarenes indicate that the thermal weight loss process of calix[4]arenes includes 2 stages: the stage of inclusion complex loss and the stage of thermal decomposition. According to Kissinger method, the average apparent activation energies (E a ) of thermal decomposition of PC4, DC4 and SC4 are 299.86 kJ/mol, 246.09 kJ/mol and 129.28 kJ/mol, respectively. Furthermore, according to the Phadnis-Deshpande model, the decomposition kinetic models of three calix[4]arene follow nucleation and nuclei growth mechanism, phase boundary mechanism and power law mechanism, respectively.