Thermal degradation studies of the reduced and oxidized poly(o-toluidine) matrix

详细信息    查看全文

• 作者：Ahmed ; Seddique M. ; Abu-Zied ; Bahaa M.
• 关键词：Poly(o-toluidine) ; Reduced ; Oxidized form ; Non-isothermal ; Isothermal ; Degradation ; Molecular mechanics calculations
• 刊名：Journal of Analytical and Applied Pyrolysis
• 出版年：2003
• 出版时间：December, 2003
• 年：2003
• 卷：70
• 期：2
• 页码：277-289
• 全文大小：323 K

文摘

Thermal degradation of poly(o-toluidine) (POT) reduced [base form (POT-EB)] and oxidized form [i.e. doped with salicylidine-aniline (SA) and/or salicylidine-o-aminophenol (SAP)] was investigated experimentally and computationally. The results of thermal (TGA) and differential thermal (DTG) gravimetric analysis suggest a higher thermal stability for the oxidized (SA or SAP-doped POT) than that for the respective reduced (POT-EB) chain. Non-isothermal degradation of the reduced POT matrix reveals hydrophilic nature about two times stronger than that for the oxidized form (SA and/or SAP-doped POT) under the same conditions. Molecular mechanics (MM+) calculations substantiate these observations. FTIR spectroscopic study of the calcined POT-EB showed that the quinoid (Q) ring (imino-structure) is thermally at least twice more stable than for that the benzenoid (B) rings (amino-structure) in the repeating unit of the polymer chain. Isothermal degradation curves [fraction decomposed (α) vs. degradation time (t in min)] of the polymers under investigation revealed that they are characteristically declaratory in shape.