Rare earth Ce based metal organic framework as efficient synergistic thermal stabilizer for PVC: Preparation and thermal stabilization behavior

Abstract

The complex production process and uneven performance seriously restrict the application of Rare earth thermal stabilizer. In this study, the thermal stability behavior of metal organic framework Ce(1,3,5-BTC)(H2O)6 (Ce-BTC) towards PVC was studied. Experimental results showed that the combination of Ce-BTC, 2,4,6-tris[di(hydroxymethyl) amino]-1,3,5-triazine (HHTT), and ESBO synergistically stabilized PVC sample displayed significantly improved initial color, meanwhile, the Ts and the time of "zinc burning" were prolonged to 55.17 and 70 min, respectively, as well. During thermal treatment, HHTT can replace the unstable chlorine atoms on the PVC chain, and the incompletely coordinated Ce ions in Ce-BTC can inhibit the further polymerization of conjugated polyenes by reacting with the alkene chain resulted from PVC degradation, these two factors synertistically inhibit the degradation of PVC. The nertralization of HCl by HHTT and ESBO can provide longer reaction time for incompletely coordinated Ce ions and chlorine atoms, delaying the autocatalytic effect of HCl.