Article

New coordination polymers. III: Oxidation of poly(vinyl alcohol) by permanganate ion in alkaline solutions. Kinetics and mechanism of formation of intermediate complex with a spectrophotometric detection of manganate(vi) transient species

Chemistry Department, Faculty of Science. Assiut University. Assiut 71516, Egypt
Polymer International (impact factor: 1.9). 02/2007; 30(1):5 - 9. DOI:10.1002/pi.4990300103 pp.5 - 9

ABSTRACT The kinetics of formation of the [PVA. MnVIO] intermediate complex have been measured by the conventional spectrophotometric technique. The rate of formation of the complex was found to be given by the expression d[Complex]/dt = k1[MnO-4][PVA−]. The results showed that the rate of formation is dependent on the base concentration. A first-order reaction in permanganate and fractional order with respect to the poly(vinyl alcohol) (PVA) concentration were observed. The activation parameters have been evaluated and a tentative reaction mechanism has been suggested.

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Keywords

[PVA
 
activation parameters
 
base concentration
 
conventional spectrophotometric technique
 
expression d[Complex]/dt
 
kinetics
 
MnVIO] intermediate complex
 
permanganate
 
PVA
 

Refat M Hassan