Poly sorption

SG sols were synthesized by hydrolysis of tetraethyloxysilane in the presence of polyelectrolyte and surfactant. Poly (vinylsulfonic acid) (PVSA) or poly (styrenesulfonic acid) (PSSA) were used as cation exchangers, Tween-20 or Triton X-100 were used as non- ionic surfactants. Obtained sol was dropped onto the surface of glass slide and dried over night. Template extraction from the composite film was performed in water- ethanol medium. The ion-exchange properties of the films were studied spectrophotometrically using adsorption of cationic dye Rhodamine 6G or Fe(Phen) and potentiometrically by sorption of protons. 

Several selective interactions by MIP membrane systems have been reported. For example, an L-phenylalanine imprinted membrane prepared by in-situ crosslinking polymerization showed different fluxes for various amino acids [44]. Yoshikawa et al. [51] have prepared molecular imprinted membranes from a membrane material which bears a tetrapeptide residue (DIDE resin (7)), using the dry phase inversion procedure. It was found that a membrane which contains an oligopeptide residue from an L-amino acid and is imprinted with an L-amino acid derivative, recognizes the L-isomer in preference to the corresponding D-isomer, and vice versa. Exceptional difference in sorption selectivity between theophylline and caffeine was observed for poly(acrylonitrile-co-acrylic acid) blend membranes prepared by the wet phase inversion technique [53]. 

Some authors have suggested the use of fluorene polymers for this kind of chromatography. Fluorinated polymers have attracted attention due to their unique adsorption properties. Polytetrafluoroethylene (PTFE) is antiadhesive, thus adsorption of hydrophobic as well as hydrophilic molecules is low. Such adsorbents possess extremely low adsorption activity and nonspecific sorption towards many compounds [109 111]. Fluorene polymers as sorbents were first suggested by Hjerten [112] in 1978 and were tested by desalting and concentration of tRN A [113]. Recently Williams et al. [114] presented a new fluorocarbon sorbent (Poly F Column, Du Pont, USA) for reversed-phase HPLC of peptides and proteins. The sorbent has 20 pm in diameter particles (pore size 30 nm, specific surface area 5 m2/g) and withstands pressure of eluent up to 135 bar. There is no limitation of pH range, however, low specific area and capacity (1.1 mg tRNA/g) and relatively low limits of working pressure do not allow the use of this sorbent for preparative chromatography. 

Nguyen, T. H., Himmelstein, K. J., and Higuchi, T., Some equilibrium and kinetic aspects of water sorption in poly(ortho esters), Int. J. Pharm.. 25, 1-12, 1985. 

Turner, D. T. (1982). Poly(methyl methacrylate) plus water. Sorption kinetics and volumetric changes. Polymer, 23, 197-202. 

Figure 15 The sorption of acetaminophen from a solution of limited volume by 10 X 4 poly (A-isopropylacry lam idc) gel, illustrating the use of Eqs. (34) and (35) to determine the diffusion coefficient of the solute. (Data from Ref. 174.)... 

D Biren, BG Kabra, SH Gehrke. Effect of initial sample anisotropy on the solvent sorption kinetics of glassy poly(2-hydroxyethyl methacrylate). Polymer 33 554-561, 1992. 

Recent investigations have indicated that the aliphatic carbon fraction, rather than aromatic fraction, was strongly correlated to HOC sorption. For instance, the sorption of phenanthrene was related to nonpolar aliphatic carbon fraction, excluding poly(methylene), but was very strongly correlated with the content of the amorphous nonpolar aliphatic domains including amorphous poly(methylene) (Mao et al. 2002). In other words, the rubbeiy, relatively low-density, and amorphous nonpolar aliphatic carbon domains are excellent for phenanthrene partitioning (Figs. 3 and 4). 

Mao J, Flundal L, Thompson M, Schmidt-Rohr K (2002) Correlation of poly(methylene)-rich amorphous aliphatic domains in humic substances with sorption of a nonpolar organic contaminant, phenanthrene. Environ Sci Technol 36 929-936... 

Fig. 6 Water vapor sorption isotherms for poly(vinylpyrrolidone) at 60°C(+) 30°C (x) -20°C ( ) and -40°C (A). Data were taken from Oksanen and Zografi [71,75]. A 0 represents the calculated water contents necessary to depress Tg to the temperature of the isotherms.

The method consists of the retention by sorption of the porphyrins on poly (vinyl alcohol) (PVA) hydrogels. Poly (vinyl alcohol) (PVA) is selected as the polymer of choice for the purification of industrial and medical wastewaters due to its capacity to form physically crosslinked hydrogels with the advantages of non-toxic, non-carcinogenic and biodegradable properties. 

Xing B. and J.J. PignateUo (1997). Dual-mode sorption of low-polarity compounds in glassy poly(vinyl chloride) and soil organic matter. Environmental Science and Technology 31 792-799. 

Due to the possible preferential sorption of one solvent component, it is a disadvantage to use a mixed solvent to produce the collapse of ionized PAAm networks. Therefore, we have measured also ionized poly (A, N -diethylacryl-amide) (PDEAAm) gels for which the phase transition can be induced by a temperature change in pure water [16]. The networks (A, B, C, D, E, F, G and H) were prepared [18] by copolymerization erf DEAAm with sodium methacrylate (mole fraction xMNa = 0,0.0045,0.0095,0.0157,0.0234,0.0310,0.0432 and 0.0667) in the presence of 93 vol % of water ([Pg.189]

Poly(vinylbenzyl chloride) (VBC) is an ideal starting material onto which a variety of functional groups can be attached through relatively simple reactions and mild reaction conditions. Functionalized polymers are of interest in a variety of applications including but not limited to fire retardants, selective sorption resins, chromatography media, controlled release devices and phase transfer catalysts. An example of the wide applicability of functionalized polymers is provided by trimethyl ammonium functionalized poly(VBC). 

Sanders, E. S., Koros, W. J., Hopfenberg, H. B., Stannett, V. T. Pure and Mixed Gas Sorption of Carbon Dioxide and Ethylene in Poly(methyl methacrylate), to be pubhshed... 

The existence of two T2 relaxation times was also observed in the radiation cured photopolymers 99), and studies of tri- and tetra-functional network organosilicon polymers with rings at the network points 100). The effects of crystallization of poly-dimethylcarbosiloxane networks (PDMCS) I01), and water sorption and stoichio-metrical composition of the cured DGEBA/DETA resins on phase structure and mobility 102) were studied. 

Fig. 4.25 Illustration of mass sensitivities to sorption of octane by poly(dimethylsiloxane) coating, of different vibrational modes (adapted from Kim et al., 2001)...

Corundum is aluminum oxide, q -A1203, which has a hexagonal crystalline structure that is analogous to hematite. However, water treatment systems most often use activated alumina, which is typically produced by thermally dehydrating aluminum (oxy)(hydr)oxides to form amorphous, cubic (y), and/or other polymorphs of corundum (Clifford and Ghurye, 2002, 220 Hlavay and Poly k, 2005 Mohan and Pittman, 2007). When compared with corundum, amorphous alumina tends to have higher surface areas, greater numbers of sorption sites, and better sorption properties. 

Hlavay and Poly k (2005) investigated the surface properties of an iron(III) hydroxide-coated alumina sorbent. Amorphous iron(III) hydroxide was coated onto a mixture of amorphous and various crystalline forms of AI2O3. The iron concentration of the sorbent was 56.1 mmol g-1. Depending on pH, batch experiments indicated that the sorbent was effective with As(V) and to some extent As(III). In a pH 5.6 solution with an ionic strength of 0.1 mmol L-1 and containing 1 mmol L-1 (75 mg As(V) L-1) of As(V), a dosage of 2.5 g sorbent 100 ml-1 of solution sorbed 0.3 mmol As(V) g-1 sorbent (22 mg As(V) g-1 sorbent). In comparison, the sorption capacity of As(III) was only about 0.06 mmol g-1 (4.5 mg As(III) g-1 sorbent) under the same conditions (Hlavay and Poly k, 2005, 76). 

Figure 7. The effect of ethylene on the sorption level of carbon dioxide in poly(methyl methacrylate) at 35 °C.

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