@article {46072,
	title = {Aromatic polyesters containing pendant azido groups: synthesis, characterization, chemical modification and thermal cross-linking},
	journal = {European Polymer Journal},
	volume = {116},
	year = {2019},
	month = {JUL},
	pages = {180-189},
	type = {Article},
	abstract = {<p>A partially bio-based bisphenol containing pendant azido group viz., 4,4{\textquoteright}-(5-azidopentane-2,2-diyl) diphenol (AZBPA) was synthesized starting from 4,4{\textquoteright}-bis (4-hydroxyphenyl) pentanoic acid. AZBPA was reacted with isophthaloyl chloride (IPC), terephthaloyl chloride (TPC) and a mixture of IPC/TPC (50:50 mol\%) by phase transfer-catalyzed interfacial polycondensation route to obtain aromatic polyesters containing pendant azido groups. Copolyesters containing pendant azido groups were also synthesized by polycondensation of different molar proportions of AZBPA and commercially available 4,4{\textquoteright}-(1-phenylethane-1,1-diyl) diphenol (BPA-AP) with IPC. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.85-1.64 dL/g and 58,900-190,400, respectively, indicating the formation of reasonably high molecular weight polymers. Tough, transparent, and flexible films could be cast from chloroform solutions of these polyesters. X-Ray diffraction analysis showed that (co)polyesters were amorphous in nature. (Co)polyesters were characterized using FT-IR, H-1 NMR spectroscopy, XRD, TGA and DSC analysis. The chemical modification of a representative copolyester containing pendant azido groups was carried out quantitatively using copper-catalyzed azide-alkyne cycloaddition (CuAAC) with two alkynes viz., phenyl acetylene (PA) and ethynyl-4-nitrobenzene (ENB). Additionally, (co)polyesters containing pendant azido groups were thermally cross-linked (170 degrees C/12 h) leading to the formation of network structures based on azide to nitrene decomposition and subsequent reactions on polyester backbone. The selected cross-linked polyesters were characterized by stress-strain measurements. The cross-linked polymers exhibited higher tensile strength and Young{\textquoteright}s modulus and lower \% elongation at break compared to corresponding pristine polyesters containing pendant azido groups.</p>
},
	keywords = {Aromatic polyester, Chemical modification, Click chemistry, Pendant azido group, Thermal cross-linking},
	issn = {0014-3057},
	doi = {10.1016/j.eurpolymj.2019.04.019},
	author = {Nagane, Samadhan S. and Verma, Savita and Tawade, V, Bhausaheb and Sane, Prakash S. and Dhanmane, Sushilkumar A. and Wadgaonkar, Prakash P.}
}
@article {48138,
	title = {Synthesis, characterization and UV-crosslinking of aromatic (Co)polycarbonates bearing pendant azido groups},
	journal = {ChemistrySelect},
	volume = {7},
	year = {2022},
	month = {SEP},
	pages = {e202201020},
	type = {Article},
	abstract = {<p>
	A new series of (co)polycarbonates bearing pendent azido groups was synthesized by polycondensation of varying molar proportions of 4, 4{\textquoteright}-(5-azidopentane-2, 2-diyl) diphenol and bisphenol-A with triphosgene. The chemical structures, compositions and random nature of (co)polycarbonates were confirmed by NMR spectroscopy. Inherent viscosities and number-average molecular weights of (co)polycarbonates were in the range 0.63-0.77 dL g(-1) and 35,400-43,400 g mol(-1), respectively indicating the formation of reasonably high molecular weight polymers. (Co)polycarbonates could be cast into tough, transparent and flexible films from chloroform solutions. (Co)polycarbonates were further characterized using IR spectroscopy, XRD, TGA and DSC. The thermal crosslinking of (co)polycarbonates bearing pendant azido groups was studied by DSC analysis. Independently, (co)polycarbonates bearing pendant azido groups were exposed to UV irradiation at wavelength of 254 nm and decomposition reaction of azido groups was monitored by FT-IR spectroscopy. The complete decomposition of azido groups was observed with exposure time of 30 min. The formed cross-linked (co)polycarbonates exhibited improved \% char yield values compared to parent (co)polycarbonates. The measurement of mechanical properties of representative crosslinked (co)polycarbonates indicated increase in tensile strength and Young{\textquoteright}s modulus and decrease in \% elongation compared to corresponding parent linear (co)polycarbonates.</p>
},
	keywords = {Aromatic polycarbonate, Pendant azido group, solution polycondensation, Triphosgene, UV-crosslinking},
	issn = {2365-6549},
	doi = {10.1002/slct.202201020},
	author = {Nagane, Samadhan S. and Kuhire, Sachin S. and Ichake, Amol B. and Talanikar, Aniket A. and Lochab, Bimlesh and Wadgaonkar, Prakash P.}
}
