Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5202953 | Polymer Degradation and Stability | 2012 | 8 Pages |
Characteristics of low temperature (473Â K) dehydrochlorination of PVC powder in the presence of ZnO were studied in nitrogen flow and a reaction mechanism was proposed. It was revealed that a large portion of chlorine (ca. 70%) in PVC powder reacts with ZnO accompanying evolution of water and a slight amount of HCl (ca. 0.5%) without any organic gas. Analysis of the solid product by SEM, XRD and IR suggested that an apparent solid-solid reaction proceeds at 473Â K via formation of a liquid phase which acts as reaction promoter and that the solid product is abundant in aliphatic (CH)n polymer. It was concluded that the first step of the dehydrochlorination is cross-linking C-C single bond formation in a polymer chain or among polymer chains followed by isomerization to polyene and aromatics.