Synthesis and characterization of siloxane copolyesters containing phenylindane linkages

A novel series of siloxane copolyesters containing 1,1,3‐trimethyl‐3‐( p ‐hydroxyphenyl)‐5‐indanol (phenylindane bisphenol), diphenyl terephthalate (DPT), diphenyl isophthalate (DPI), and eugenol end‐capped siloxanes in varying ratios were prepared at a temperature range of 200–290°C under reduced pressure using dibutyl tin dilaurate catalyst by melt polycondensation. The siloxane‐containing copolyesters were characterized by infrared and 1 H NMR spectroscopy, elemental analysis, solution viscosity, thermogravimetric analysis, differential scanning calorimetry, and X‐ray diffraction. The effect of incorporation of siloxane moiety was studied on the properties of phenyl indane/DPT/DPI coplyester. The glass transition temperatures of copolyesters were decreased from 235 to 124°C by incorporation of 10% eugenol end‐capped siloxane without affecting the thermal properties. All copolyesters were found to be soluble in commonly used organic solvents and had film forming properties. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2668–2674, 2006