UV-vis spectroscopy for following the kinetics of homogeneous polymerization of diphenylamine in p-toluene sulphonic acid.
Kinetics of chemical oxidative polymerization of diphenylamine (DPA) was followed in aqueous 1M para-toluene sulphonic acid (p-TSA) using potassium peroxomonosulphate (PMS) or peroxodisulphate (PDS), independently as an oxidant. The medium was found to be homogeneous and became dark green in colour during the course of polymerisation. The course of polymerization was followed by UV-vis spectroscopy. Rate of polymerization (R(p)) was determined for various conditions by following the absorbance values corresponding to poly(diphenylamine) (PDPA) for different concentrations of DPA and PMS or PDS at various time intervals of polymerization. The observed dependences of DPA, PDS or PMS on R(p) were used to deduce rate equations for PDS or PMS initiated polymerization of DPA. The rate constant for the formation of poly(diphenylamine), was estimated. In situ spectroelectrochemical studies on the polymerization of DPA were also carried out on an ITO electrode in 1M p-TSA. The results are in accordance with the intermediates suggested in chemical oxidative polymerization.
Nagarajan
S
S
Department of Industrial Chemistry, Alagappa University, Karaikudi, 630003 Tamil Nadu, India.
Santhosh
P
P
Sankarasubramanian
M
M
Vasudevan
T
T
Gopalan
A
A
Lee
Kwnag-Pill
KP
D001557:Benzenesulfonates / Q000737:chemistry*; D004159:Diphenylamine / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods; D007700:Kinetics; D008958:Models, Molecular; D011108:Polymers; D013053:Spectrophotometry; D013056:Spectrophotometry, Ultraviolet
D001557:Benzenesulfonates; D011108:Polymers; D004159:Diphenylamine; C029501:4-toluenesulfonic acid