Synthesis and Physico-Chemical Characterization of Halogenated Partly Aromatic Cardo Copolyesters

Copolyesters of 1,1′-bis(3-methyl-5-chloro-4-hydroxy phenyl) cyclohexane (0.0025 mol), ethylene glycol/propylene glycol/1, 4-butanediol/1,6-hexanediol (0.0025 mol) and terephthaloyl chloride (0.005 mol) have been synthesized by interfacial polycondensation technique by using water-chloroform (4:1 v/v) as an interphase, sodium hydroxide (0.125 mol) as an acid acceptor and cetyl trimethyl ammonium bromide (50 mg) as an emulsifier. The reaction time and temperature were 3 h and 0°C, respectively. The yield of copolymers was 85–87%. Copolyesters are soluble in common solvents and possess moderate molecular weights. The structures of copolyesters are supported by FT-IR and ¹HNMR spectral data. Copolyesters are characterized for their viscosity in chloroform and 1,2-dichloroethane at 30, 35 and 40°C, densities by floatation method (1.139–1.2775 g cm^?3). It is observed that both [η] and density of copolyesters decreased with increase in alkyl chain length. Copolyesters possess excellent hydrolytic stability against water and 10% each of acids, alkalis and salt at room temperature. The observed wt. % change is ±3.15% in the selected environments. A 30 μm thick C1MPT film has 17.8 MPa tensile strength, 50.1 kV mm^?1 electric strength and 2.2 × 10¹² ohm cm volume resistivity. Copolyesters possess high T_g (148–172°C) and are thermally stable up to about 411–426°C and followed single step degradation kinetics involving 70–75% weight loss with 20–24% residual weight above 650°C. Copolyesters followed 1.19–1.94 order degradation kinetics. Activation energy and frequency factors are increased with alkyl chain length.