Synthesis, spectral, and thermal characterization of photosensitive poly(ether-ester)s containing α,β-unsaturated ketone moieties in the main chain derived from 2,6-bis[4-(3-hydroxypropyloxy)-3-methoxybenzylidene]cyclohexanone

Abstract

A series of photosensitive poly(ether–ester)s containing α,β-unsaturated ketone moieties in the main chain were synthesized from 2,6-bis[4-(3-hydroxypropyloxy)-3-methoxybenzylidene]cyclohexanone (BHPMBCH) and aliphatic and aromatic diacid chlorides. The diol precursor, BHPMBCH, was synthesized from 2,6-bis(4-hydroxy-3-methoxybenzylidene)cyclohexanone and 3-bromo-1-propanol. The solubility of the polymers was tested in various solvents. The intrinsic viscosity of the synthesized polymers, determined by an Oswald viscometer, was found to be 0.06–0.80 g/dL. The molecular structures of the monomer and polymers were confirmed by Fourier transform infrared, ultraviolet–visible, 1H-NMR, and 13C-NMR spectral analyses. The thermal properties were studied with thermogravimetric analysis and differential scanning calorimetry. The thermogravimetric analysis data revealed that the polymers were stable up to 220°C and started degrading thereafter. The thermal stability initially increased with increasing spacer length and then decreased due to negative effects of the spacer. The self-extinguishing properties of the synthesized polymers were studied by the determination of the limiting oxygen index values with Van Krevelen's equation. In addition, the photocrosslinking properties of the polymer chain were studied with UV spectroscopy, and we observed that the rate of photocrosslinking increased significantly with increasing methylene carbon chain length of the acid spacer. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011