Organic thermal stabilizers for rigid poly(vinyl chloride). Part XI: Anthraquinone derivatives

• Published in: Polymer degradation and stability 2006-02, Vol.91 (2), p.242-254
• Main Authors: Sabaa, Magdy W., Oraby, Emad H., Abdel Naby, Abir S., Mohamed, Riham R.
• Format: Article
• Language: English
• Subjects: Applied sciences; Blends; Compounding ingredients; Degradation; Exact sciences and technology; Extent of discoloration; Induction period (Ts); Poly(vinyl chloride); Polymer industry, paints, wood; Stabilizers (antioxydants, antiozonants, etc.); Technology of polymers; Thermal stability
• ISSN: 0141-3910; 1873-2321
• DOI: 10.1016/j.polymdegradstab.2005.05.011

Anthraquinone and 1-aminoanthraquinone derivatives have been examined as thermal stabilizers or co-stabilizers for rigid PVC in air, at 180 °C. Their high stabilizing efficiency is detected by their high induction period values (Ts) when compared with some of the common reference stabilizers used industrially such as dibasic lead carbonate, calcium–zinc soap and octyl tin mercaptide. Blending these organic stabilizers with some of the reference stabilizers in different ratios had synergistic effect on both the induction period and the dehydrochlorination rate. A probable mechanism for the stabilizing mode of these derivatives has been proposed. The stabilizing efficiency is attributed partially to the stabilizers' ability to intervene in the radical chain degradation process of PVC and to the replacement of the labile chlorine atoms on PVC chains by a relatively more stable moiety of the organic stabilizer.