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Coordination polymers acquired much interest due to their powerful applications. Herein, coordination polymer of the formula {[Fe(PZDC)Cl(H2O)2]}n has been prepared conventionally and ultrasonically. The structure was investigated using elemental analysis, IR and X-ray diffraction (XRD). The ultrasonic-assisted synthesis steers the formation of the crystalline coordination polymer while the conventional method leads to the amorphous phase. Calcination of the synthesized coordination polymers was made in glass tubes (length = 200 mm and width = 15 mm) under air at variable temperatures. Depending on the calcination conditions, different iron oxide phases/polymorphs were produced. Maghemite; γ-Fe2O3 was formed by heat-treatment at 350 °C for 1 h regardless of the synthesis way of the precursor. X-ray single phase of hematite; α-Fe2O3 was obtained by calcination of the conventionally prepared precursor at 450 °C for 1 h. Nitrogen adsorption-desorption isotherms showed that, the specific surface areas of the γ-Fe2O3 (conventionally produced precursor), γ-Fe2O3 (ultrasonically formed precursor) and α-Fe2O3 are 125, 132 and 30.5 m2g-1, respectively. Magnetic measurements showed that the best properties are exhibited by γ-Fe2O3 NPs synthesized from the conventionally prepared precursor; highest values of saturation magnetization (Ms), remanent magnetization (Mr) and coercivity (Hc) are obtained. On the other hand α-Fe2O3 showed the lowest magnetic properties. The activity of prepared coordination polymers and iron oxide phases for removal of methylene blue (MB) was tested. γ-Fe2O3 (conventionally formed precursor) showed the highest adsorption efficiency (∼22%). On the other side, the coordination polymer (conventionally prepared) exhibited the best removal efficiency of methylene blue in a Fenton-like process. Degradation efficiency of 97.2% was achieved in a very short time (15 min).

Hypothesis \ud Adsorption of hydrophobically modified ethoxylated urethane polymers (HEURs) at the soft colloid interfaces of emulsion droplets will stabilise oil-in-water emulsions (a) via steric stabilisation induced by adsorption of the polymer at the droplet surfaces through the hydrophobic groups, and (b) via continuous phase viscosity enhancement through polymer self-association. Both of these mechanisms will be modulated by the presence of the surfactant, sodium dodecylsulfate (SDS).\ud \ud Experiments\ud Dodecane-in-water emulsions stabilised by three HEUR polymers with different structural composition were examined in the absence and presence of SDS by NMR spectroscopy and small-angle neutron scattering (SANS). The effect of adsorption of the polymer to the dodecane droplet surfaces, and the conformation of the self-associating polymer in the aqueous solution were quantified.\ud \ud Findings\ud All emulsions were stable for days-weeks. Diffusion data showed the formation of oil droplets of hundreds of nm in size in the presence of all three HEURs, here denoted C6-L-(EO100-L)9-C6, C10-L-(EO200-L)4-C10, and C18-L-(EO200-L)7-C18, where EOx represents a block of ethylene oxide of x monomers, L denotes the linker group, and Cn the length of the hydrophobic end-group. No significant changes in droplet size across this series of polymers was observed. Collectively, the results point to adsorption of the polymer to the droplet surfaces, which results in a small decrease in the effective polymer solution concentration, thereby driving to significant changes in the structure and dynamics of the system. Evident in the SANS data in particular, is a subtle balance between the characteristic features reflecting polymer self-association, and those associated with polymer structures commensurate with a larger length-scale, dependent on the system composition. Surprisingly, the polymer and polymer/SDS complex in the presence of oil show slightly greater diffusive rates relative to the analogous systems in the absence of the oil. Finally, the partitioning of the three polymers in phase-separated samples was studied by 1H NMR, and it was shown that the C18-L-(EO200-L)7-C18 exhibited a greater partitioning in the oil phase compared with C6-L-(EO100-L)9-C6 and C10-L-(EO200-L)4-C10, an observation that may be understood in terms of the structural composition of the HEURs. The SDS showed a positive correlation between its partitioning in the two layers with the polymer partitioning, evidence of a strong interaction between the surfactant and the polymer, consistent with the behaviour observed in the oil-free system.

Hypothesis:\ud Hydrophobically modified ethoxylated urethane polymers (HEURs) are widely used to control the rheological profile of formulated particulate dispersions through associative network formation, the properties of which are perturbed by the presence of surfactants. At high polymer concentrations and in the presence of surfactants, it is hypothesised that the dominant factors in determining the rheological profile are the number and composition of the mixed hydrophobic aggregates, these being defined by the number and distribution of the hydrophobic linkers along the polymer backbone, rather than the end-group hydrophobe characteristics per se that dominate the low polymer concentration behaviour. \ud \ud Experiments:\ud Three different HEUR polymers with formulae (C6-L-(EO100-L)9-C6, C10-L-(EO200-L)4-C10 and C18-L-(EO200-L)7-C18 (where L = urethane linker, Cn = hydrophobic end-group chain length, and EO = ethylene oxide block) have been studied in the absence and presence of SDS employing techniques that quantify (a) the bulk characteristics of the polymersurfactant blend, (b) the structure and composition of the hydrophobic domains, (c) the dynamics of the polymer and surfactant, and (d) the polymer conformation. Collectively, these experiments demonstrate how molecular-level interactions between the HEURs and sodium dodecylsulphate (SDS) define the macroscopic behaviour of the polymer/surfactant mixture.\ud \ud Findings:\ud Binding of the SDS to the polymer via two mechanisms - monomeric anti-cooperative and micellar cooperative - leads to surfactant-concentration-specific macroscopic changes in the viscosity. Binding of the surfactant to the polymer drives a conformational rearrangement, and an associated redistribution of the polymer end-groups and linker associations throughout the hydrophobic domains. The composition and size of these domains are sensitive to the polymer architecture. Therefore, there is a complex balance between polymer molecular weight, ethylene oxide block size, and number of urethane linkers, coupled with the size of the hydrophobic end-groups. In particular, the urethane linkers are shown to play a hitherto largely neglected but important role in driving the polymer association.

Drug delivery via the eye, nose, gastrointestinal tract and lung is of great interest as they represent patient-compliant and facile methods to administer drugs. However, for a drug to reach the systemic circulation it must penetrate the "mucus barrier". An understanding of the characteristics of the mucus barrier is therefore important in the design of mucus penetrating drug delivery vehicles e.g. nanoparticles. Here, a range of nanoparticles - silica, aluminium coated silica, poly (lactic-co-glycolic acid) (PLGA) and PEGylated PLGA - each with known but different physicochemical characteristics were examined in the presence of mucin to identify those characteristics that engender nanoparticle/mucin interactions and thus, to define "design rules" for mucus penetrating (nano)particles (MPP), at least in terms of the surface characteristics of charge and hydrophilicity. Dynamic light scattering (DLS) and rheology have been used to assess the interaction between such nanoparticles and mucin. It was found that negatively charged and hydrophilic nanoparticles do not exhibit an interaction with mucin whereas positively charged and hydrophobic nanoparticles show a strong interaction. Surface grafted poly (ethylene glycol) (PEG) chains significantly reduced this interaction. This study clearly demonstrates that the established colloid science techniques of DLS and rheology are very powerful screening tools to probe nanoparticle/mucin interactions.

Polymer blends based on carboxymethylcellulose (CMC) and gum arabic (GA) were prepared by solution casting method. Glycerol was added to the polymer blend solution as a plasticizer with different ratios (2·5, 5, 10 and 20%). Then, the plasticized blends were exposed to gamma irradiation at different doses (5, 10 and 20 kGy). The physical properties of the plasticized polymer blends were investigated in terms of gel fraction (%) and swelling percent (%). Thermal properties were investigated by TGA. Also, the structure of the plasticized polymer blends was characterized by Fourier transform infrared spectroscopy. Scanning electron microscope was investigated in order to examine the compatibility between two polymers in the blend and also between polymer blend and plasticizer. The prepared plasticized polymer blends were used as an adsorbent for different dyestuffs. The sorption of dyestuffs by the plasticized polymer blend was determined by a method based on spectroscopic analysis. The results showed that the plasticized polymer blend has a high affinity for basic, acid, reactive and direct dyes. The obtained results showed that using glycerol as plasticizer improved the swellability of polymer blend and also the dye uptake (%).

With strict regulation of environmental pollution, sunflower fatty acids were used to prepare high-molecular-weight aromatic amine adducts by reaction of their epoxidized form [epoxidized sunflower free fatty acid (ESFA)] with five aromatic amines [o-toluidine (o-T), m-toluidine (m-T), p-toluidine (p-T), p-anizidine (p-A), and p-chloroaniline (p-ClA)] under severe conditions of an inert atmosphere and high temperature. The produced adducts were characterized physically, chemically, and by IR spectroscopy. The acid values and oxirane contents of the prepared adducts were determined to confirm the participation of carboxylic groups and epoxy groups, respectively, in the reaction of ESFA with aromatic amines. Also, to avoid volatile organic compounds, the prepared adducts of ESFA (o-T–ESFA, m-T–ESFA, p-T–ESFA, p-A–ESFA, and p-ClA–ESFA) were evaluated as corrosion inhibitors of mild steel in electron-beam-curable epoxy acrylate oligomer formulations. Physical and mechanical measurements were carried out, in addition to corrosion-resistance tests and weight loss measurements of the coated steel panels. The optimum concentration of each adduct was determined for the prepared formulations. The corrosion-inhibition efficiency of the adducts in varnish formulations were determined. It was found that varnish formulations containing the prepared aromatic amine adducts could protect steel from corrosion. The corrosion-inhibition efficiencies of the prepared aromatic amines in epoxy acrylate oligomer varnishes were arranged as follows: p-A–ESFA > p-T–ESFA > m-T–ESFA > o-T–ESFA > p-ClA–ESFA. Superior corrosion-inhibition efficiency was obtained in the varnish formula containing 0.6% p-A–ESFA adduct. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012

Epoxy acrylate oligomer (EA) was plasticized by adding different plasticizers such as epoxidized soybean oil, glycerol and castor oil and cured by electron beam (EB). Different irradiation doses (1, 2.5 and 5 Mrad pass−1) were used in the curing process. The effect of both different irradiation doses and plasticizers on the end use performance properties of epoxy acrylate coating namely, pencil hardness, bending test, adhesion test, acid and alkali resistance test were studied. It was observed that incorporation of castor oil in epoxy acrylate diluted by 1,6-hexanediol diacrylate (HD) monomer with a ratio (EA 70%, HD 20%, castor oil 10%) under 1 Mrad pass−1 irradiation dose improved the physical, chemical and mechanical properties of cured films than the other plasticizer. Sunflower free fatty acid was epoxidized in situ under well established conditions. The epoxidized sunflower free fatty acids (ESFA) were subjected to react with aniline in sealed ampoules under inert atmosphere at 140 °C. The produced adducts were added at different concentrations to epoxy acrylate coatings under certain EB irradiation dose and then evaluated as corrosion inhibitors for carbon steel surfaces in terms of weight loss measurements and corrosion resistance tests. It was found that, addition of 0.4 g of aniline adduct to 100 g epoxy acrylate formula may give the best corrosion protection for carbon steel and compete the commercial corrosion inhibitor efficiency with the same concentration.

Linear electron beam radiation has been used to induce irradiation grafting of glycidyl methacrylate (GMA), glycidyl methacrylate/β-cyclodextrin (GMA/β-CD), and glycidyl methacrylate/monochlorotriazinyl-β-cyclodextrin (GMA/MCT-β-CD) onto cotton fabrics. The effect of radiation dose, GMA concentration and CDs concentration on graft yield, epoxide content and the bonded amount of CDs was investigated. Results obtained reveal that the amount of CDs bonded within the fabric; the add-on and the epoxide content are directly related to the CDs concentration, GMA concentration and the irradiation dose. Graft yield and epoxide content increase with the increase of radiation dose to a certain extent, and they decrease due to degradation of GMA at higher irradiation doses. Results also reveal that although the bonded amount of CDs is nearly proportional to the concentration of CDs in the treatment solution, the accessibility ratio of CDs decreases with increasing CDs concentration. Treatment of fabrics grafted with GMA (Cell-g-GMA) and GMA/CDs mixtures (Cell-g-GMA/CDs) in a sequel step with the corresponding CDs increases the amounts of CDs fixed onto the fabrics, while epoxide content decreases. The treatment of the cotton fabrics with GMA and CDs was established on the basis of spectral data studies.

This work is a part of long program for producing natural polymers which is used for application in different purposes in agriculture fields. A part of this program was the preparation of various compositions of Gum Arabic (GA) and Poly vinyl alcohol (PVA) with studying its physical and chemical characters. Whereas, the present work was concerning with the evaluation of released amount of selected micronutrients from the same complex under laboratory and field conditions. In the laboratory, the prepared complex containing copper (Cu) or manganese (Mn) separately, were tested at different pH values for releasing at intervals. The obtained results showed the possibility of using the Mn+2 complex at 3000 mg kg−1. Moreover, the obtained results showed that the maximum released amount was obtained at pH 7.0. A field experiment was planed according to the resulted data obtained in laboratory. Samples were taken for elemental analysis either from soil or plants during all growth stages likeas vegetative, floweri...

Polymer blends based on various compositions of natural macromolecule gum arabic (GA) and poly vinyl alcohol (PVA) were prepared by solution casting technique. It was found that the maximum concentration of gum from which a compatible blend can be obtained was found to be from 10–30%. Compatible blend were exposed to gamma irradiation at different doses of 20, 30, and 50 kGy to evaluate the effect of irradiation on different properties of the blend. Physical, thermal and mechanical properties of the blend were investigated. Also, structural properties in terms of scanning electron microscope (SEM) were studied. The Results obtained show a decrease in glass transition temperature of the blend with increasing GA content. Moreover, there is an improvement in mechanical properties in terms of stress-strain behavior.

A study has been made to modify different textile fabrics such as cotton, cotton/polyester blend and nylon-6 fabrics by surface coating with a constant thickness layer of 25 μm of aqueous solution of polyvinyl alcohol (PVA) and acrylic acid (AAc). Radiation curing of surface coating was accomplished by electron beam irradiation with a constant dose of 50 kGy. Parameters affecting hydrophilicity of cured coated fabrics, namely, presence or absence of cross-linking agent and concentration of AAc in coating solution, were investigated. Properties affiliated with hydrophilicity, specifically water uptake and weight loss, before and after several washing cycles were followed up. Crease recovery angle was determined. Considerable enhancement, in water uptake as well as crease recovery angle, has been attained with increasing AAc content in solution in case of nylon-6, followed by blends and then cotton. Moreover, dyeing properties for coated fabrics, with solution containing 4 wt.% AAc, has been tested by color difference method, for basic and reactive dyes. Relative increase in color strength has been achieved. The presence of cross-linking agent in coating solution played a significant role, specifically in case of dyeing properties. Morphology of coated fabrics was examined by scanning electron microscope (SEM), which indicated fastness and compatibility between coating and fabrics. Correlation between structure and obtained results was given.