Polyacrylic Acid

Swelling of modifi ed polyacrylic acid hydrogels under conditions of a photoinitiated polymerization of acrylic acid to give a sealing hydrogel for fi reproof multiple glazing units was studied. Mechanisms by which crosslinks are formed in the gel are suggested and the possibility of controlling the degrees of swelling and crosslinking is discussed.

Vanadium oxide gels are appealing cathode materials as they offer multiple electron redox processes leading to high cation‐storage capacities. Moreover, they are able to intercalate different ionic and molecular species. Apart from low electronic conductivity, one of the main factors hindering the use of highly porous V2O5 gels is the difficulty in preserving their unique morphology, made up of an entangled network of thin ribbons, during conventional laminated electrode preparation. In this study, we tune the V2O5 synthesis conditions and use an innovative and green binder system (polyacrylic acid and ethanol) to obtain electrodes with a morphology optimized for ion intercalation. The electrochemical performance of such electrodes, tested against lithium and sodium anodes, are shown to be excellent.

In this study, aqueous solutions containing mixtures of heavy metals namely Zn (II), Pb (II), Cr (III), and Cr (VI) were treated by polymer-enhanced ultrafiltration (PEUF) using unmodified starch as binding biopolymer. The performance of starch in removing these heavy metals was compared with that of polyethylene glycol (PEG) a commonly used polymer in PEUF processes. Rejection coefficients and flux were studied under different values of pH solution and metal ion concentrations maintaining the transmembrane pressure constant at 1.5 bar. At pH 7, and starch concentration of 0.05%, the rejection was the highest at around 90%. As metal ion concentration increased from 10 to 50 mg/L, the rejection of metal ions decreased. It was found that starch gave higher rejection for Zn (II) and Cr (III) at 0.05 g/L of polymer concentration, whereas 1 g/L of PEG concentration gave higher rejection for Cr (VI) at 10 mg/L. The influence of metal ion concentration on Pb (II) rejection is not significant for the two selected polymers. The rejection of these metal ions by starch in this study is found to be influenced by granule structure that generally behaved in a non-ionic manner. (c) 2014 American Institute of Chemical Engineers Environ Prog, 34: 359-367, 2015

http://onlinelibrary.wiley.com/doi/10.1002/ep.11995/full
http://onlinelibrary.wiley.com/store/10.1002/ep.11995/asset/ep11995.pdf?v=1&t=i9c7hlfh&s=895e45e663147014dd138501e790f110807b8248

Conversion‐enabled transition metal oxides are mostly characterized by environmental benignity, low cost, and high theoretical capacities, which make them suitable as candidate anode materials for Li‐ion batteries. To ensure high efficiency and stability, the use of novel and tailored morphologies is recommended. Among the other methods, the use of natural extracts as templates is one of the possible strategies to accomplish this task. In this work, Fe2O3 nanoparticles are synthesized by using vanillin as a soft templating agent, and fully characterized on a morphological, structural and electrochemical level. Poly(acrylic acid) binder and ethanol for electrode preparation ensure a fully environmentally benign process from synthesis to electrode testing. The cells deliver capacity values up to 700 mAh g−1 under prolonged galvanostatic cycling at 500 mA g−1, as well as excellent rate capability and high efficiency.

Conversion‐enabled transition metal oxides are mostly characterized by environmental benignity, low cost, and high theoretical capacities, which make them suitable as candidate anode materials for Li‐ion batteries. To ensure high efficiency and stability, the use of novel and tailored morphologies is recommended. Among the other methods, the use of natural extracts as templates is one of the possible strategies to accomplish this task. In this work, Fe2O3 nanoparticles are synthesized by using vanillin as a soft templating agent, and fully characterized on a morphological, structural and electrochemical level. Poly(acrylic acid) binder and ethanol for electrode preparation ensure a fully environmentally benign process from synthesis to electrode testing. The cells deliver capacity values up to 700 mAh g−1 under prolonged galvanostatic cycling at 500 mA g−1, as well as excellent rate capability and high efficiency.