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Adsorptive Properties (adsorptive + property)
Selected AbstractsCompatibility studies with blends based on poly(n -butyl methacrylate) and polyacrylonitrileJOURNAL OF APPLIED POLYMER SCIENCE, Issue 6 2010Zhaogang Ge Abstract In this study, poly(n -butyl methacrylate) (PBMA) was prepared by a suspension polymerization process, and blending with polyacrylonitrile (PAN) in N,N -dimethyl acetamide to prepare PAN/PBMA blends in various proportions. Hansen's three dimensional solubility parameters of PAN and PBMA were calculated approximately through the contributions of the structural groups. The compatibility in these blend systems was studied with theoretical calculations as well as experimental measurements. Viscometric methods, Fourier transform infrared spectroscopy, dynamic mechanical analysis, scanning electron microscopy, and thermogravimetric analysis were used for this investigation. All the results showed that a partial compatibility existed in PAN/PBMA blend system, which may be due to the intermolecular interactions between the two polymers. And, the adsorption experiment results showed that the addition of PBMA contributed to the enhancing adsorptive properties of blend fibers, which lays the foundation for further studying PAN/PBMA blend fibers with adsorptive function. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [source] Nutshells as granular activated carbons: physical, chemical and adsorptive properties,JOURNAL OF CHEMICAL TECHNOLOGY & BIOTECHNOLOGY, Issue 5 2001H Wartelle Abstract Nutshells from seven different sources (pistachio, hazelnut, almond, black walnut, English walnut, macadamia nut, pecan) were converted to granular activated carbons (GACs) by carbon dioxide activation. A portion of the GACs were oxidized with compressed air and the physical (yield, surface area, attrition), chemical (pH, surface charge) and adsorptive (organics uptake, metal ion uptake) properties of both oxidized and non-oxidized carbons were determined. Differences in uptake of organics, especially of polar compounds, were found between GACs made from almond shells, the group consisting of black walnut shells, English walnut shells and pecan shells, and macadamia nutshells. Oxidation had its greatest effects on pH, surface charge and uptake of metal ions. The changes due to oxidation were found to be independent of carbon source material. GACs with specific properties can be produced with judicious selection of carbon precursor and oxidative treatment. © 2001 Society of Chemical Industry [source] Sensitive determination of phenols in environmental water samples with SPE packed with bamboo carbon prior to HPLCJOURNAL OF SEPARATION SCIENCE, JSS, Issue 4 2009Ru-Song Zhao Abstract Bamboo carbon, an inexpensive, readily available material, has attracted great attention in recent years because of adsorptive properties. In this paper, the potential of bamboo carbon as a SPE adsorbent for the determination of phenols, was investigated. Phenols are important environmental contaminants that may adversely affect human health. Parameters influencing extraction efficiency, including type of eluent, eluent volume, amount of adsorbent, as well as sample pH, volume, and flow rate were investigated and optimized. The optimized results exhibited excellent linear relationships between peak area and phenol concentrations over the range of 2.0,100 ng/mL, with precision between 2.2,7.2%. The LODs were 0.06,0.4 ng/mL for the eight phenols tested. The proposed method has been successfully applied to the analysis of several real-world environmental water samples. These results indicate that bamboo carbon may be used as a novel SPE adsorbent for the concentration and determination of phenols in real environmental water samples. [source] Biodegradable Polylactide and Its Nanocomposites: Opening a New Dimension for Plastics and CompositesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 14 2003Suprakas Sinha Ray Abstract The academic and industrial aspects of the preparation, characterization, mechanical and materials properties, crystallization behavior, melt rheology, and foam processing of pure polylactide (PLA) and PLA/layered silicate nanocomposites are described in this feature article. Recently, these materials have attracted considerable interest in polymer science research. PLA is linear aliphatic thermoplastic polyester and is made from agricultural products. Hectorite and montmorillonite are among the most commonly used smectite-type layered silicates for the preparation of nanocomposites. Smectites are a valuable mineral class for industrial applications because of their high cation exchange capacities, surface area, surface reactivity, adsorptive properties, and, in the case of hectorite, high viscosity, and transparency in solution. In their pristine form, they are hydrophilic in nature, and this property makes them very difficult to disperse into a polymer matrix. The most common way to overcome this difficulty is to replace interlayer cations with quaternized ammonium or phosphonium cations, preferably with long alkyl chains. In general, polymer/layered silicate nanocomposites are of three different types: (1) intercalated nanocomposites, in which insertion of polymer chains into the layered silicate structure occurs in a crystallographically regular fashion, regardless of polymer to layered silicate ratio, with a repeat distance of few nanometer; (2) flocculated nanocomposites, in which intercalated and stacked silicate layers are sometimes flocculated due to the hydroxylated edge,edge interactions between the silicate layers; (3) exfoliated nanocomposites, in which individual silicate layers are uniformly distributed in the polymer matrix by average distances that totally depend on the layered silicate loading. This new family of composite materials frequently exhibits remarkable improvements in its material properties when compared with those of virgin PLA. Improved properties can include a high storage modulus both in the solid and melt states, increased flexural properties, a decrease in gas permeability, increased heat distortion temperature, an increase in the rate of biodegradability of pure PLA, and so forth. Illustration of the biodegradability of PLA and various nanocomposites. [source] | |||||||||||||