Non-isothermal degradation kinetics of poly (2,2'-dihydroxybiphenyl)


DOĞAN F. , KAYA İ. , Bilici A.

POLYMER BULLETIN, cilt.63, ss.267-282, 2009 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 63 Konu: 2
  • Basım Tarihi: 2009
  • Doi Numarası: 10.1007/s00289-009-0084-5
  • Dergi Adı: POLYMER BULLETIN
  • Sayfa Sayıları: ss.267-282

Özet

Catalytic oxidative polymerization of 2,2'-dihydroxybiphenyl (DHBP) was performed by using Schiff base polymer-Cu (II) complex and hydrogen peroxide as catalyst and oxidant, respectively. According to size exclusion chromatography (SEC) analysis, the number-average molecular weight (M (n)), weight-average molecular weight (M (w)) and polydispersity index (PDI) values of poly (2,2'-dihydroxybiphenyl) (PDHBP) were found to be 37,500, 90,000 g mol(-1) and 2.4, respectively. The thermal degradation kinetics was investigated by thermogravimetric analysis in dynamic nitrogen atmosphere at four different heating rates: 5, 10, 15 and 20 A degrees C min(-1). The derivative thermogravimetry curves of PDHBP showed that its thermal degradation process had one weight-loss step. The apparent activation energies of thermal decomposition for PDHBP as determined by Tang, Flynn-Wall-Ozawa (FWO), Kissenger-Akahira-Sunose (KAS), Coats-Redfern (CR) and Invariant kinetic parameter (IKP) methods were 109.1, 109.0, 110.0, 108.4 and 109.8 kJ mol(-1), respectively. The mechanism function and pre-exponential factor were determined by master plots and Criado-Malek-Ortega method. The most likely decomposition process was a D (n) Deceleration type in terms of the CR, master plots and Criado-Malek-Ortega results.