02858nas a2200265 4500008004100000022001400041245013400055210006900189260000800258300001200266490000800278520193200286653002302218653002602241653002002267653002402287653002602311100002502337700001802362700000502380700002202385700003002407700002802437856012702465 2019 eng d a0014-305700aAromatic polyesters containing pendant azido groups: synthesis, characterization, chemical modification and thermal cross-linking0 aAromatic polyesters containing pendant azido groups synthesis ch cJUL a180-1890 v1163 a

A partially bio-based bisphenol containing pendant azido group viz., 4,4'-(5-azidopentane-2,2-diyl) diphenol (AZBPA) was synthesized starting from 4,4'-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'-(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's modulus and lower % elongation at break compared to corresponding pristine polyesters containing pendant azido groups.

10aAromatic polyester10aChemical modification10aClick chemistry10aPendant azido group10aThermal cross-linking1 aNagane, Samadhan, S.1 aVerma, Savita1 a1 aSane, Prakash, S.1 aDhanmane, Sushilkumar, A.1 aWadgaonkar, Prakash, P. uhttps://library.ncl.res.in/content/aromatic-polyesters-containing-pendant-azido-groups-synthesis-characterization-chemical02465nas a2200253 4500008004100000022001400041245010100055210006900156260000900225300001400234490000700248520158800255653002701843653001601870653002001886653002601906100002201932700002501954700002101979700002502000700002602025700002802051856013202079 2019 eng d a0887-624X00aNew cardo bisphenol monomer containing pendant azido group and the resulting aromatic polyesters0 aNew cardo bisphenol monomer containing pendant azido group and t cJUL  a1516-15260 v573 a

Expanding on our strategy to synthesize aromatic step-growth polymers containing pendant clickable azido groups via functional monomer approach, we have now designed and synthesized a new cardo bisphenol, viz., 2-(2-azidoethyl)-3, 3-bis(4-hydroxyphenyl) isoindolin-1-one (PPH-N-3). PPH-N-3 was conveniently synthesized starting from commercially available phenolphthalein by a three-step route in an overall yield of 65% using simple organic transformations. Aromatic (co)polyesters bearing pendant azido groups were synthesized by low-temperature solution polycondensation of PPH-N-3 or different molar ratios of PPH-N-3 and bisphenol-A (BPA) with aromatic diacid chlorides in dry dichloromethane in the presence of triethylamine (TEA) as a base. The formation of medium to reasonably high-molecular-weight (co)polyesters was evidenced from intrinsic viscosity and number-average molecular-weight measurements that were in the range 0.52-0.85 dL/g and 16,700-28,200, respectively. Tough, transparent, and flexible films could be cast from chloroform solutions of these (co)polyesters. (Co)polyesters were characterized using FTIR, H-1 NMR, C-13 NMR spectroscopy, XRD, and TGA. The thermal curing reaction of (co)polyesters involving decomposition of azido groups was studied by DSC analysis. The chemical modification of a representative copolyester containing pendant azido groups was carried out quantitatively using catalyst-free azide-maleimide cycloaddition reaction with two maleimides, namely, N-methylmaleimide and N-hexylmaleimide. (c) 2019 Wiley Periodicals, Inc.

10aaromatic (co)polyester10aazido group10acardo bisphenol10aChemical modification1 aMaher, Deepak, M.1 aNagane, Samadhan, S.1 aJadhav, Uday, A.1 aSalunkhe, Pravin, H.1 aTawade, Bhausaheb, V.1 aWadgaonkar, Prakash, P. uhttps://library.ncl.res.in/content/new-cardo-bisphenol-monomer-containing-pendant-azido-group-and-resulting-aromatic-polyesters02543nas a2200253 4500008004100000022001400041245012700055210006900182260000800251300001200259490000700271520162900278653002701907653002601934653002401960653002501984653002902009100002502038700002202063700001802085700002602103700002802129856013202157 2022 eng d a1060-132500aPendant propargyloxy-functionalized aromatic (co)polycarbonates: synthesis, thermal crosslinking and chemical modification0 aPendant propargyloxyfunctionalized aromatic copolycarbonates syn cNOV a752-7630 v593 a

A bisphenol monomer bearing pendant propargyloxy group viz, 1, 1-bis (4-hydoxyphenyl)-1-(4 `-propargyloxyphenyl) ethane (BPP) was synthesized starting from commercially available 1, 1, 1-tris (4-hydroxyphenyl) ethane (THPE) by mono O-propargylation reaction using propargyl bromide. A new series of pendant propargyloxy-functionalized aromatic (co)polycarbonates was synthesized by low-temperature solution polycondensation of BPP or different molar ratios of BPP and bisphenol-A with triphosgene in dichloromethane in the presence of triethylamine. The formation of reasonably high molecular weight (co)polycarbonates was confirmed by inherent viscosity (0.52-0.83 dL/g) and gel permeation chromatography (M-n 37,000-69,800 g/mol, polystyrene standards) measurements. C-13 NMR spectral studies supported formation of random copolycarbonates in copolymerization of BPP and BPA with triphosgene. The 10% weight loss temperature (T-10) values of (co)polycarbonates, determined by thermogravimetric analysis under nitrogen atmosphere, were in the range 427-438 degrees C indicating their good thermal stability. The glass transition temperature (T-g) values of (co)polycarbonates were observed in the range 147-152 degrees C. The crosslinking ability of (co)polycarbonates involving pendant propargyloxy groups leading to formation of networked structure was evaluated via non-isothermal curing studies by DSC. As a proof-of-concept, the post-modification of a representative polycarbonate bearing pendant propargyloxy groups with 1-octane thiol as a model compound via thiol-yne click reaction was briefly studied.

10aAromatic polycarbonate10aChemical modification10apropargyloxy groups10athermal crosslinking10athiol-yne click reaction1 aNagane, Samadhan, S.1 aMaher, Deepak, M.1 aVerma, Savita1 aTalanikar, Aniket, A.1 aWadgaonkar, Prakash, P. uhttps://library.ncl.res.in/content/pendant-propargyloxy-functionalized-aromatic-copolycarbonates-synthesis-thermal-crosslinking