02316nas a2200193 4500008004100000245013900041210006900180260000800249300001400257490000700271520160300278653001101881653001301892653001901905100002201924700001701946700002801963856013101991 2017 eng d00aHealable network polymers bearing flexible poly(Lauryl Methacrylate) chains via thermo-reversible furan-maleimide diels-alder reaction0 aHealable network polymers bearing flexible polyLauryl Methacryla cAUG a2700-27120 v553 aA new ATRP initiator containing two furyl rings, namely, bis(furan-2-ylmethyl) 2-bromopentanedioate was synthesized starting from commercially available L-glutamic acid as a precursor. Well-defined bisfuryl-terminated poly(lauryl methacrylate) macromonomers with molecular weight and dispersity in the range 5000-12,000 g mol(-1) and 1.30-1.37, respectively, were synthesized employing the initiator by atom transfer radical polymerization (ATRP). Independently, 1,1',1"(nitrilotris(ethane-2,1-diyl)) tris(1H-pyrrole-2,5-dione) was synthesized as a tris-maleimide counterpart for furan-maleimide click reaction. Thermo-reversible network polymer bearing flexible poly(lauryl methacrylate; (PLMA) chains was obtained by furan-maleimide Diels-Alder click reaction of bisfurylterminated PLMA with 1,1',1"-(nitrilotris(ethane-2,1-diyl)) tris(1Hpyrrole-2,5-dione). The prepared network polymer showed retro-Diels-Alder reaction in the temperature range 110-170 degrees C as determined from DSC analysis. The presence of low Tg (-40 degrees C) PLMA chains induced chain mobility to the network structure which led to the complete scratch healing of the coating at 60 degrees C in five days due to furan-maleimide adduct formation. The storage modulus of the network polymer was found to be 3.7 x 10(4) Pa at the constant angular frequency of 5 rad/ sec and strain of 0.5%. The regular reversal of storage (G0) and loss modulus (G") was observed with repeated heating (40 to 110 degrees C) and cooling cycles (110 to 40 degrees C) at constant angular frequency and strain. (C) 2017 Wiley Periodicals, Inc.10aethane10aMonomers10apolymerization1 aPatil, Sachin, S.1 aTorris, Arun1 aWadgaonkar, Prakash, P. uhttps://library.ncl.res.in/content/healable-network-polymers-bearing-flexible-polylauryl-methacrylate-chains-thermo-reversible02687nas a2200361 4500008004100000022001400041245021300055210006900268260000800337300001400345490000700359520141200366653002201778653002601800653003401826653001101860653001301871653001501884653001401899653002301913653002401936653002501960653003301985653002502018653001802043653002502061653001302086100002302099700002002122700002302142700002802165856013202193 2017 eng d a0887-624X00aPartially bio-based poly(amide imide)s by polycondensation of aromatic diacylhydrazides based on lignin-derived phenolic acids and aromatic dianhydrides: synthesis, characterization, and computational studies0 aPartially biobased polyamide imides by polycondensation of aroma cNOV a3636-36450 v553 a

Two new bio-based diacylhydrazide monomers, namely, 4,4-(propane-1,3-diylbis(oxy))bis(3-methoxybenzohydrazide) and 4,4-(propane-1,3-diylbis(oxy))bis(3,5-dimethoxybenzohydrazide) were synthesized starting from lignin-derived phenolic acids, namely, vanillic acid and syringic acid. A series of poly(amide imide)s was synthesized by polycondensation of these diacylhydrazide monomers with commercially available aromatic dianhydrides. Poly(amide imide)s showed inherent viscosity in the range 0.44-0.56 dLg(-1) and exhibited good solubility in organic solvents. Poly(amide imide)s could be cast into transparent, flexible, and tough films from their N,N-dimethylacetamide solutions. Poly(amide imide)s showed 10% weight loss in the temperature range 340-364 degrees C indicating their good thermal stability. Glass transition temperature (T-g) of poly(amide imides)s were measured by DSC and DMA which were in the range 201-223 degrees C and 214-248 degrees C, respectively. The T-g values of poly(amide imide)s were dependent on the number methoxy substituents on aromatic rings of diacylhydrazide monomers. Molecular dynamics simulation studies revealed that chain rigidity is the dominant factor for observed trends in T-g. (c) 2017 Wiley Periodicals, Inc.

10aBiobased Polymers10aComputational studies10aGlass-transaction temperature10alignin10aMonomers10aPlant oils10aPolyimide10aReneable resources10aRenewable resources10aStep-growth polymers10astructure-property relations10aSustanaible Polymers10aThermal night10aThermosetting resins10aVanillin1 aKuhire, Sachin, S.1 aSharma, Pragati1 aChakrabarty, Suman1 aWadgaonkar, Prakash, P. uhttps://library.ncl.res.in/content/partially-bio-based-polyamide-imides-polycondensation-aromatic-diacylhydrazides-based-lignin01565nas a2200229 4500008004100000022001400041245009000055210006900145260000800214300001600222490000600238520083700244653001301081653001501094653001101109653001301120653002401133653001701157100002201174700002201196856011701218 2019 eng d a2365-654900aAltering the O/C ratio of lignin derived monomers without sacrificing atom efficiency0 aAltering the OC ratio of lignin derived monomers without sacrifi cDEC a14050-140550 v43 a

Synthesis of platform and fuel grade chemicals from lignin without losing atom efficiency and lowering O/C ratio is a challenge in a bio-refinery concept. In this work, we report solid acid catalysed alkylation of lignin derived variety of monomers such as guaiacol, veretrole, phenol, anisole, and catechol using numerous alcohols as alkylating agents. Results elaborate that the type of acidity and structure of catalyst play important role in achieving higher dialkylated products (DAP). With 85% conversion of guaiacol, 30.9% DAP formation was achieved at 250 degrees C within 2 h. A unique substrate adsorption study on the catalyst surface and effect of solubility of substrates on the activity of catalyst is evaluated. Catalyst was observed to be recyclable with marginal loss in the activity due to handling error.

10aAlcohols10aAlkylation10alignin10aMonomers10asolid acid catalyst10aUp-gradation1 aSingh, Dheerendra1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/altering-oc-ratio-lignin-derived-monomers-without-sacrificing-atom-efficiency