Thermoanalytical Study and Kinetics of New 8‐Hydroxyquinoline 5‐sulphonic Acid‐Oxamide‐Formaldehyde Terpolymer Resins

Abstract

The terpolymer resins (8-HQ5-SAOF) have been synthesized by the condensation of 8-hydroxyquinoline 5-sulphonic acid (8-HQ5-SA) and oxamide (O) with formaldehyde (F) in the presence of acid catalyst and using varied molar proportion of the reacting monomers. The synthesized terpolymer resins have been characterized by different physico-chemical techniques. Thermogravimetric analysis of all terpolymer resins in present study have been carried out by non-isothermal thermogravimetric analysis technique in which sample is subjected to condition of continuous increase in temperature at linear rate. Thermal study of the resins was carried out to determine their mode of decomposition and relative thermal stabilities. Thermal decomposition curves were studied carefully with minute details. The Freeman-Carroll and Sharp-Wentworth methods have been used in the present investigation to calculate thermal activation energy and different kinetic parameter of the terpolymer resins. Thermal activation energy (Ea) calculated with above two mentioned methods are in close agreement. The advantage of Freeman-Carroll method is to calculate both the order of reaction (n) and energy of activation in one single stage by keeping heating rate constant. By using data of thermogravimetric analysis, various thermodynamic parameters like frequency factor (Z), entropy change (Δ S), free energy change (Δ F) and apparent entropy (S*) have been determined using Freeman-Carroll method.

Synthesis and Semiconducting Behavior of Terpolymer Resin-I Derived from Sulphanilic Acid, Melamine and Formaldehyde

“…A peak at 1126 cm −1 was due to the stretching vibrations of Ar-S bond in SO 3 H composite 24 . 1327 cm −1 and 1165 cm -1 region corresponds to S=O antisymetric and symmetric stretching in sulphanilic acid 14,25 . FT-IR spectral data is given in Table 3.…”

“…The number average molecular weights (Mn) of SAMF-I terpolymer was determined by non-aqueous conductometric titration in DMF using 0.1 M KOH in absolute alcohol as titrant. From the graphs of specific conductance against miliequivalents of base, first and last break were noted from which degree of polymerization (DP) and the number average molecular weight (Mn) was calculated for terpolymer resin using following equation 14 . DP = (Total milliequivalents of the base required for last break) milliequivalents of the base required for first break Mn = DP x Molecular weight of the repeating unit The repeating unit weight was obtained from elemental analysis.…”

“…Also band at, 910 cm -1 , 814 cm -1 and 665 cm -1 , all of them were assigned to -NH-bending, wagging and deformation out of plane vibrations in terpolymer resin respectively. The absorption band at1650-1580 cm -1 was assigned to N-H bending vibration of primary amines 14,18 . The band at 837-820 cm -1 was due to tetra substituted benzene ring 23 .…”

“…The region 1186-1034 cm -1 was assigned to C-N stretch in primary and secondary amines due to weak band at 605.7 cm -1 and 735 cm -1 which were assigned to C-S str. of aromatic ring and SO 3 H group 14 . A peak at 1126 cm −1 was due to the stretching vibrations of Ar-S bond in SO 3 H composite 24 .…”

Thermal Degradation Studies of Terpolymer Derived from 2-Aminothiophenol, Hexamethylenediamine, and Formaldehyde

“…The thermal stability of terpolymers has been extensively studied by employing the method of thermogravimetric analysis (TGA) by several authors [12][13][14][15][16][17][18][19][20][21]. Thermoanalytical and kinetic studies of terpolymer resins derived from 8-hydroxyquinoline-5-sulphonic acid/p-cresol, oxamide/melamine with formaldehyde have been reported by Singru et al [12,13]. Thermal and metal ion bonding properties of terpolymer resin synthesized from resorcinol-thioureaformaldehyde have been reported by Karunakaran et al [14].…”