02148nas a2200265 4500008004100000022001400041245010600055210006900161260000900230300001100239490000800250520122800258653002901486653003101515653002401546653001701570653001001587100002601597700002201623700002401645700002401669700003301693700002401726856013201750 2020 eng d a0014-305700aRenewing polyethylene: insertion copolymerization of sugar derived hydrophilic monomers with ethylene0 aRenewing polyethylene insertion copolymerization of sugar derive cJUL  a1097750 v1343 a

Although highly desirable, insertion copolymerization of renewable resource derived functional olefins with ethylene has been rarely investigated. Herein, we report insertion copolymerization of challenging sugar derived isohexide mono-enes with ethylene in the presence of Pd-phosphinesulfonate acetonitrile catalyst (C1). Thus, copolymerization of ethylene with isomannide mono-ene (2a), isosorbide mono-ene (2b'), isoidide mono-ene (2c) and methacryl-2,3,4,6-tetra-O-acetyl-D glucopyranoside (2d) afforded corresponding functionalized polyethylene (P2a-1 to P2d-1). High temperature proton NMR investigations revealed enchainment of 2a-2c in polyethylene backbone and the highest incorporation of 1.45% was observed for 2c. The high temperature proton NMR results were further corroborated by solid state C-13 NMR and IR spectroscopy. Gel permeation chromatography analysis displayed weight average molecular weight in the range of 13.0-27.2 x 10(3) g/mol. The thus prepared copolymers revealed melting temperature in the range of 117-126 degrees C. Relatively reduced melting temperature compared to neat polyethylene may suggest an irregular arrangement of pendant functional group on polyethylene main chain.

10aHydrophilic polyethylene10ainsertion copolymerization10aIsohexide mono-enes10aPolyethylene10aSugar1 aRajput, Bhausaheb, S.1 aPawal, Sandip, B.1 aBodkhe, Dnyaneshwar1 aRao, Nagamalleswara1 aSainath, Annadanam, V. Sesha1 aChikkali, Samir, H. uhttps://library.ncl.res.in/content/renewing-polyethylene-insertion-copolymerization-sugar-derived-hydrophilic-monomers-ethylene11157nas a2200217 45000080041000000220014000412450135000552100069001902600008002593000011002674900008002785201038200286653002410668653001810692653001810710653001010728653001910738100002110757700002210778856013910800 2021 eng d a0008-621500aElucidating the effect of solid base on the hydrogenation of C5 and C6 sugars over Pt–Sn bimetallic catalyst at room temperature0 aElucidating the effect of solid base on the hydrogenation of C5  cJUL a1083410 v5053 a

Conversion of sugars into sugar alcohols at room temperature with exceedingly high yields are achieved over Pt–Sn/γ-Al2O3 catalyst in the presence of calcined hydrotalcite. pH of the reaction mixture significantly affects the conversion and selectivity for sugar alcohols. Selection of a suitable base is the key to achieve optimum yields. Various solid bases in combination with Pt–Sn/γ-Al2O3 catalysts were evaluated for hydrogenation of sugars. Amongst all combinations, the mixture (1:1 wt/wt) of Pt–Sn/γ-Al2O3 and calcined hydrotalcite showed the best results. Hydrotalcite helps to make the pH of reaction mixture alkaline at which sugar molecules undergo ring opening. The sugar molecule in open chain form has carbonyl group which can be polarized by Sn in Pt–Sn/γ-Al2O3 and Pt facilitates the hydrogenation. In the current work, effect of both; solid base and Sn as a promoter has been studied to improve the yields of sugar alcohols from various C5 and C6 sugars at very mild reaction conditions.

10aBimetallic catalyst10aHydrogenation10aHydrotalcites10aSugar10aSugar alcohols1 aTathod, Anup, P.1 aDhepe, Paresh, L. uhttps://library.ncl.res.in/content/elucidating-effect-solid-base-hydrogenation-c5-and-c6-sugars-over-pt%E2%80%93sn-bimetallic-catalyst