Synthesis of CaZnAl-CO3 ternary layered double hydroxides and its application on thermal stability of poly (vinyl chloride) resin

In this work, hydrothermal method was used to prepare the CaZnAl-CO3 ternary layered double hydroxides (CaZnAl-CO3-LDHs) with various Ca/Zn/Al molar ratios, which were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscope (FT-IR) and scanning electron microscopy (SEM) techniques. The obtained results demonstrate that the samples were well-crystallized and flake-structured. The CaZnAl-CO3-LDHs used alone for thermal stability of poly (vinyl chloride) (PVC) resin, with different Ca/Zn/Al molar ratios and varying additive amounts, were investigated through the tests such as static thermal aging, mass loss and congo red, respectively. The optimum Ca/Zn/Al molar ratio and additive amount were 3.6:0.4:2 and 5 phr (parts per hundred PVC resin), respectively. In addition, the synergistic effects of Ca3.6Zn(0).4Al(2)-CO3-LDHs and CaSt2 were discussed in detail, showing better thermal stability compared with Ca3.6Zn(0.4)Al(2)-CO3-LDHs used alone, and the optimum additive amounts of Ca3.6Zn(0.4)Al(2)-LDHs and CaSt(2) were 6 and 1.0 phr, respectively.