01697nas a2200205   4500008004100000022001400041245010300055210006900158260007100227300001600298490000800314520090100322100002901223700002401252700001501276700002401291700002101315700003201336856012301368       2015                        eng d  a1520-610600aInsights into the molecular dynamics in polysulfone polymers from C-13 solid-state NMR experiments0 aInsights into the molecular dynamics in polysulfone polymers fro  a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcAUG  a11287-112940 v1193 a<p>The molecular and segmental motions in three different grades of ductile polysulfone polymers; poly(ether sulfone) (PESU), polysulfone (PSU), and poly(phenyl sulfone) (PPSU) are probed using C-13 solid-state NMR experiments. Polarization inversion spin exchange at magic angle (PISEMA) experiments indicates that the phenyl rings in the polymers are undergoing pi-flip motions on the order of 100 kHz. The temperature dependent PISEMA experiments show that the fraction of mobile regions that undergoes aromatic pi-flips is higher in PPSU than in the other two polymers. The center band only detection of exchange (CODEX) experiments was carried out and was unable to detect any slow segmental motions in the chains. A combination of C-13 spin-lattice relaxation time (T-1) and T-1-filtered PISEMA experiments show that the mobile regions in all the polymers are dynamically heterogeneous.</p>1 aEldho, Kavalakal, Mathai1 aRajamohanan, P., R.1 aAnto, Ralf1 aBulakh, Neelima, N.1 aLele, Ashish, K.1 aAjithkumar, Thalasseril, G.  uhttps://library.ncl.res.in/content/insights-molecular-dynamics-polysulfone-polymers-c-13-solid-state-nmr-experiments-001386nas a2200205   4500008004100000022001400041245011200055210006900167260009000236300001000326490000600336520055300342100002000895700002400915700002900939700002400968700003200992700003001024856012601054       2016                        eng d  a2045-232200a1000-fold enhancement in proton conductivity of a MOF using post-synthetically anchored proton transporters0 a1000fold enhancement in proton conductivity of a MOF using posts  aMACMILLAN BUILDING, 4 CRINAN ST, LONDON N1 9XW, ENGLANDbNATURE PUBLISHING GROUPcAUG  a324890 v63 a<p>Pyridinol, a coordinating zwitter-ionic species serves as stoichiometrically loadable and non-leachable proton carrier. The partial replacement of the pyridinol by stronger hydrogen bonding, coordinating guest, ethylene glycol (EG), offers 1000-fold enhancement in conductivity (10(-6) to 10(-3) Scm(-1)) with record low activation energy (0.11 eV). Atomic modeling coupled with C-13-SSNMR provides insights into the potential proton conduction pathway functionalized with post-synthetically anchored dynamic proton transporting EG moieties.</p>1 aShalini, Sorout1 aDhavale, Vishal, M.1 aEldho, Kavalakal, Mathai1 aKurungot, Sreekumar1 aAjithkumar, Thalasseril, G.1 aVaidhyanathan, Ramanathan  uhttps://library.ncl.res.in/content/1000-fold-enhancement-proton-conductivity-mof-using-post-synthetically-anchored-proton01893nas a2200193   4500008004100000245006700041210006700108260000800175300001200183490000700195520124100202100003401443700002901477700002401506700003201530700001701562700002701579856009301606       2017                        eng d00aMolecular motifs for additives that retard PEO crystallization0 aMolecular motifs for additives that retard PEO crystallization  cAUG  a857-8640 v573 a<p>We investigate the influence of several bifunctional phenol additives (resorcinol: RES, hydroquinone: HYD, p-hydroxybenzoic acid: PHBA, and p-nitrophenol: PNP) on the crystallization of matrix polymer, polyethyleneoxide. We employ solid state Nuclear Magnetic Resonance spectroscopy (NMR), Differential Scanning Calorimetry (DSC), optical microscopy, and Small Angle X-ray Scattering (SAXS) to investigate crystallization of the additivated PEO and compare with Density Functional Theory (DFT) calculations of additive-PEO interactions. Additive-polymer interactions are a function of the functional groups on the additive. Temperature-dependent spherulitic growth rate measurements from optical microscopy and SAXS lamellar long spacings indicate a distinct trend in the effect of additives on PEO crystallization. Change in PEO crystallization is most pronounced with PNP, followed by PHBA and finally RES and HYD. This trend correlates qualitatively with the binding energies of additive-PEO interactions from DFT studies. Our results suggest that DFT calculations might be a useful screening tool to evaluate the influence of additives on polymer crystallization. POLYM. ENG. SCI., 2016. © 2016 Society of Plastics Engineers</p>1 aShrivastava, Sudhakar, Dinesh1 aEldho, Kavalakal, Mathai1 aRajamohanan, P., R.1 aAjithkumar, Thalasseril, G.1 aVanka, Kumar1 aKumaraswamy, Guruswamy  uhttps://library.ncl.res.in/content/molecular-motifs-additives-retard-peo-crystallization