Synthesis and thermal characterization of poly(1,3-phenyl octanoate)

✍ Scribed by S. Rajalekshmi; M. Saminathan; C. K. S. Pillai; C. P. Prabhakaran

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 435 KB
• Volume: 34
• Category: Article
• ISSN: 0887-624X
• DOI: 10.1002/(sici)1099-0518(199610)34:14<2851::aid-pola2>3.0.co;2-u

✦ Synopsis

Poly( 1,3-phenyl octanoate) (polyHPOA) was prepared by melt and solution polycondensation methods from 8-(3-hydroxyphenyl)octanoic acid (HPOA), a novel monomer useful as a chain disruptor in liquid crystalline copolyesters. The melt polycondensation technique gave a polyester of higher inherent viscosity (0.80 dL/g in p-chlorophenol) than that (0.75 and 0.56 dL/g, respectively, for the Ogata method and thionyl chloride/pyridine method in the same solvent) of' solution techniques. T h e solubility of the polyesters was limited to strongly acidic and polar solvents. The polyester was characterized by elemental analysis, IR spectroscopy, WAXD, TGA, isothermal TGA and DTA. x-ray diffraction pattern of the polyesters indicated that it is amorphous in nature. TGA of the polyesters gave a thermal stability of 470°C in nitrogen atmosphere a t 50% decomposition. The available thermal data suggest that the polyester undergoes thermal decomposition by a pyrolytic cleavage involving the ester linkage with the formation of ketene and phenol ended groups as intermediates. (