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The synthesis and radical polymerization of methacrylamide having Gabapentin (GBP) moieties were examined. The monomer was prepared by reaction of methyl-1-aminomethyl-1-cyclohexane acetic acid salt with methacryloyl chloride in presence of triethylamine in moderate yields. Radical polymerizations of the monomer were carried out in presence of AIBN (3 mol%) in DMF in moderate yield. The thermal behaviour of the polymers was investigated by thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) to determine the thermal degradation pattern and glass transition temperature (Tg). The resulting polymer showed a thermal stability up to ~ 400ºC. We found the molecular weight of the polymer to be 4340 g/mol (Mw/Mn=1.33) and poly[N-[(1-1-methoxyformoyl-1''-methyl) cyclohexylmethyl] methacrylamide] (poly[MFCHM]) were soluble in common solvents.

The kinetics of melt polyesterification of adipic acid with hexamethylene glycol in an equimolar ratio has been studied over a temperature range of 120ºC to 150ºC in the absence and presence of p-toluene sulphonic acid (PTSA) or diphenylammonium triflate (DPAT) as catalyst. The rate equations for polymerizations fit the rate equations proposed by Tang-Yao for 80-480 min. For acid-catalyzed and non-catalyzed polyesterifications at various temperatures, plots of 1/(1-p) and 1/(1-p)3/2 have been made against time, respectively. The fits test accuracy was also ensured by the least squares method. The experimental results show that reaction orders are 2.5 and 2 for uncatalyzed and acid-catalyzed reactions, respectively, with up to 97% conversion. The rate constants and activation energies for uncatalyzed and acid-catalyzed reactions were calculated. The activation energies are 45.01 kJ/mol for the self-catalyzed system, 35.32 kJ/mol for DPAT catalyzed system and 31.55 kJ/mol for PTSA catalyzed system. Activation energies are compared to literature data for polyesterification reactions of adipic acid with hexamethylene glycol in equimolar quantities. We found that the catalytic activity of DPAT in polycondensation is similar to that of PTSA.

The direct polycondensation of dicarboxylic acids with diols using diphenylammonium triflate (DPAT) as catalyst is described. We investigated the solvent effect on molecular weight in the polyesterification reactions, influence of the reaction period for a fixed catalyst amount. Also, to determine the effect of catalyst the reaction between succinic acid and 1,6-hexanediol using different catalyst amounts for the constant time was examined. Different types of polyesters were synthesized via solution polycondensation using DPAT catalyst. Molecular weights of the synthesized polymers were determined using GPC and an Ubbelohde viscosimeter. It is found that the molecular weights of polyhexamethylene succinate, polyhexamethylene adipate, polydecamethylene adipate, polyhexamethylene sebecate, polybutylene adipate and polyethylene adipate, are 12900 g/mol, 13300 g/mol, 8400 g/mol, 8100 g/mol, 2750 g/mol and 2600 g/mol, respectively. The polyesters were characterized by 1H NMR and FTIR spectroscopy. DPAT gave the highest yields of polyhexamethylene succinate and polydecamethylene adipate (93%). It is found that toluene is the best solvent, an appropriate reaction period is 12 h and the optimum catalyst amount is 0.25 mol% for polyesterification. DPAT is efficient for the synthesis of aliphatic polyesters under mild conditions because of the polycondensation, it was revealed that DPAT seems to catalyze not only the esterification but also etherification is catalyzed as a side reaction.