No abstract

GG-g-(AA-co-AM-co-APA) IPN superadsorbent, characterization of loaded microstructures and individual/synergistic adsorption mechanism of MB/SF/Pb(ii)/Cd(ii)/Cu(ii) are reported.

Superadsorbent hydrogel with excellent physicochemical properties is used for mere/synergic chemisorption of dyes and M(ii).

Here, redox active aliphatic luminescent polymers (ALPs) are synthesized via polymerization of N,N‐dimethyl‐2‐propenamide (DMPA) and 2‐methyl‐2‐propenoic acid (MPA). The structures and properties of the optimum ALP3, ALP3‐aggregate and Cu(I)‐ALP3, ratiometric pH sensing, redox activity, aggregation enhanced emission (AEE), Stokes shift, and oxygen‐donor selective coordination‐reduction of Cu(II) to Cu(I) are explored via spectroscopic, microscopic, density functional theory‐reduced density gradient (DFT‐RDG), fluorescence quenching, adsorption isotherm‐thermodynamics, and electrochemical methods. The intense blue and green fluorescence of ALP3 emerges at pH = 7.0 and 9.0, respectively, due to alteration of fluorophores from –C(═O)N(CH3)2/ –C(═O)OH to –C(O−)═N+(CH3)2/ –C(═O)O−, inferred from binding energies at 401.32 eV (–C(O−)═N+(CH3)2) and 533.08 eV (–C(═O)O–), significant red shifting in absorption and emission spectra, and peak at 2154 cm−1. The n−π* communications in ALP3‐aggregate, hydrogen bondings within 2.34–2.93 Å (intramolecular) in ALP3 and within 1.66–2.89 Å (intermolecular) in ALP3‐aggregate, respectively, contribute significantly in fluorescence, confirmed from NMR titration, ratiometric pH sensing, AEE, excitation dependent emission, and Stokes shift and DFT‐RDG analyses. For ALP3, Stokes shift, excellent limit of detection, adsorption capacity, and redox potentials are 13561 cm−1/1.68 eV, 0.137 ppb, 122.93 mg g−1, and 0.33/−1.04 V at pH 7.0, respectively.

Carbon black (N‐330), organically modified nanoclay (NC) based ternary, particulate nanocomposites comprising of epoxidized natural rubber matrix having 25 mol% of epoxy group (ENR‐25) were prepared in an open two‐roll mill. Investigations of cure characteristics, dynamic mechanical, tensile, thermal, and morphological characteristics were conducted using Rheometric analysis, Dynamic Mechanical Analysis (DMA), mechanical property evaluation, Thermo‐gravimetric analysis (TGA), High Resolution Transmission Electron Microscopy (HR‐TEM), respectively, to derive the interrelation among the developed nanostructures inside the composite, crosslinking density, performance properties obtained there from. A satisfactory level of correlation was obtained among various results, which indicated the formation of “nanounit” comprising of N‐330 and NC inside ENR‐25 matrix. To optimize the nanostructures, ENR based compounds containing various combinations of NC and N‐330 was prepared. Thorough and systematic structure‐property analyses were performed on those composites. Optimum stoichiometric combination of N‐330 and NC inside the ENR‐25 matrix was derived (ratio of N‐330 and nanoclay in wt% = 20:15), which showed synergistic effect of one filler upon another that was ultimately reflected in their dynamic mechanical and tensile properties. POLYM. COMPOS., 2010. © 2009 Society of Plastics Engineers