International Journal of Scientific & Technology Research Volume 1,Issue 1,Feb 2012 ISSN 22778616 1 IJSTR'2012 Synthesis and Characterisation of Two Random Copolyesters by Phase-Transfer-Catalysed Polycondensation Senthamizh Selvi R, Nanthini R and Sukanyaa G Abstract - Polyesters containing chalcone moiety were synthesised from 1, 3-bis (4-hydroxy-3-methoxyphenyl) propenone (BHMPP) and 1- (3, 5-dihydroxyphenyl)-3-(4-methoxyphenyl) propenone (DHPMPP) with suberoyl and sebacoyl chlorides by an interfacial polycondensation technique. Fundamental studies on the two phase polycondensation using phase transfer catalyst (tetra n- butylammonium bromide) was done. The synthesised polymers were characterised by solubility measurement, intrinsic viscosity, IR, 1H and 13C NMR studies. Intex Terms - Copolyesters; spectral studies; phase-transfer catalyst; polycondensation    1 INTRODUCTION The family of polyesters comprises all polymers with ester functional groups in the polymer back bone [1]. In principle, the synthesis of polyesters or esters in the presence of large amount of water has only been studied by a few research groups. Saam et al. studied the polycondensation in suspension of hydrophobic diol and diacid compounds using different sulfonate surfactants [2-4]. They defined the principles of such polycondensation and showed that polyesters of low molecular weight could be obtained in aqueous media. More recently, Manabe et al. studied the esterification of hydrophobic mono-functional compounds in aqueous suspension [5-7]. Copolyesters, obtained from a multiplicity of reactions having the component groups linked in a random or statistical order, are termed random copolyesters. They retain their strength, clarity and other mechanical properties, despite being exposed to a variety of chemicals that typically affect other materials, such as polycarbonates. This includes their  Senthamizh Selvi R and Nanthini R Postgraduate and Research Department of Chemistry, Pachaiyappas College, Chennai-600 030, India.  Sukanyaa G Queen Marys College for Women (Autonomous), Chennai-600 005, India senthamizh1980@gmail.com versatility and flexibility which enhances their application effectively in the design of high-volume, low cast parts as well as critical, more expensive component parts. Phase transfer catalysis is a synthetic technique which involves transport of an organic or inorganic salt form a solid or aqueous phase into an organic/liquid phase where reaction with an organic soluble substrate takes place. Chalcones are 1, 3-diphenyl-2-propene-1-one, in which two aromatic rings are linked by a three carbon α, β-unsaturated carbonyl system. They possess conjugated double bonds and a completely delocalised π-electron system on both benzene rings [8]. Molecules possessing such system have relatively low redox potentials and have a greater probability of undergoing electron transfer reactions. Most of the research studies involved only the polymers with side chain chalcone units. There are only few reports on soluble polymers with chalcone units in the main chain. Incorporation of flexible aliphatic chain segments into the polymer backbone improves the solubility. The present work deals with the synthesis and characterisation of polyesters containing chalcone chromophore in the main chain and study of their properties. 2 EXPERIMENTAL PROCEDURE 2.1 Materials Adipic acid (Ranbaxy), sebacic acid (SDS) and thionyl chloride (SDS) were purchased and used [9]. 4-hydroxy benzaldehyde (Merck), 4-hydroxy-3-methoxy benzaldehyde