Article

Synthesis, Characterization and Thermal Degradation of Substituted Acetophenone Based Terpolymers Having Biological Activities

Journal of Macromolecular Science Part A (Impact Factor: 0.74). 06/2011; 48(6):482-492. DOI: 10.1080/10601325.2011.573367

ABSTRACT The terpolymer resins have been synthesized by the condensation of p- hydroxyacetophenone and p-chloroacetophenone with formaldehyde/furfuraldehyde in the presence of catalyst in 1:1:5 molar proportions of reactants. The molecular structures were confirmed by FT-IR and Pyrolysis GC-MS. The number average molecular weights of these resins were determined by conductometric titration in non-aqueous medium. Viscometric measurements in tetrahydrofuran (THF) have been carried out with a view to ascertaining the characterstic functions and constant. Detailed thermal degradation studies of the terpolymer have been carried out to ascertain its thermal stability. A multiple linear regression (MLR) method has been used to calculate activation energies and frequency factor. Formaldehyde based terpolymer (Ea= 22.3 KJ/mol, Z = 0.77) has a greater activation energy and frequency factor as compared to furfuraldehyde based terpolymer (Ea=18.8 KJ/mol, Z = 0.25). Thermodynamic parameters such as free energy (G), entropy change (S*) and rate constant (kr) have also been evaluated on the basis of data of the Ozawa, Flynn and Wall method. All the synthesized polymers have shown excellent antimicrobial activities as compared to the standard Ciprofloxacin and Amphotericin-B drugs.

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Available from: Narendra P S Chauhan, Jun 28, 2015
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