Preparation of Magnesium-Aluminum Hydrotalcite by Mechanochemical Method and Its Application as Heat Stabilizer in poly(vinyl chloride)

Abstract

The traditional methods for preparing magnesium aluminum layered double hydrotalcite (Mg ₂Al-CO ₃LDHs) in industry include coprecipitation and hydrothermal methods. Both these methods have the disadvantages of high preparation cost and complicated water washing process. Using Mg(OH) ₂, Al(OH) ₃, and CO ₂ as raw materials in this work, the Mg ₂Al-CO ₃ LDHs are successfully prepared by mechanochemical method, which solves the shortcomings of traditional preparation method and realizes the conversion and utilization of CO ₂ resource. The prepared Mg ₂Al-CO ₃ LDHs are evaluated as a heat stabilizer in poly(vinyl chloride) (PVC). The result indicates that, when 2.4 phr Mg ₂Al-CO ₃ LDHs, 0.3 phr ZnSt ₂, and 0.3 phr of zinc acetylacetonate are added to the PVC, the thermal stability time of PVC can reach 190 min, which is better than PVC containing commercial Mg ₂Al-CO ₃ LDHs. Meanwhile, its processing performance is basically the same as the PVC containing commercial Mg ₂Al-CO ₃ LDHs.