a b s t r a c tThermal stability, hydration and mechanical properties of thermally cross-linked sulfonated aromatic polymers (SAP) with high ionic exchange capacity (IEC) were measured and compared to untreated samples. The formation of cross-linking greatly stabilizes sulfonated polyphenylsulfone (SPPSU) in terms of thermal, mechanical, and hydrolytic degradation: it can resist in water even at a temperature of 145• C with improved mechanical properties, while TGA experiments demonstrate that SPPSU membranes are stable well above 200• C. Sulfonated polyethersulfone (SPES) membranes show, instead, a hydrolytic instability.

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New methacrylate monomers, namely 4-methacryloyloxyphenyl-4 -fluorostyryl ketone and 4-methacryloyloxyphenyl-4 -ethylstyryl ketone comprising a free radical polymerizable group and a photocrosslinkable group, were synthesized by reacting the respective hydroxychalcones with methacryloyl chloride in the presence of triethylamine. The monomers were polymerized in the presence of ethyl methyl ketone (EMK) at 70• C using benzoyl peroxide as the initiator. The chemical structures were characterized using various spectroscopic techniques: ultraviolet, Fourier transform infrared, 1 H NMR and 13 C NMR. The thermal stability of the polymers was studied using thermogravimetric analysis in nitrogen atmosphere. Differential scanning calorimetry was used to determine the glass transition temperature of the homopolymers. Photocrosslinking of the synthesized homopolymers was investigated in solution. The two homopolymers were crosslinked within 10-15 min. After crosslinking, the homopolymers were insoluble in the same solvent.

Two acrylate monomers – 4‐(2′‐methoxycinnamoyl)phenyl acrylate, and 4‐(2′,5′‐dimethoxycinnamoyl)phenyl acrylate – comprising photocrosslinkable pendant chalcone moiety and a free radical polymerizable group were synthesized. The monomers were polymerized in the presence of ethyl methyl ketone at 70°C using benzoyl peroxide as the initiator. The polymers were characterized by UV, FT‐IR, 1H‐NMR, and 13C‐NMR spectra. The weight and number average molecular weights of the polymers were determined by gel permeation chromatography. The thermal stability of the polymers was studied by TGA under a nitrogen atmosphere. Glass transition temperatures of the polymers were studied by differential scanning calorimetry. The photoreactivity of the polymers was investigated for potential applications as photoresists in solution using various solvents. Copyright © 2008 John Wiley & Sons, Ltd.

A novel, economic, simple, precise and time-efficient reverse-phase high performance liquid chromatographic (RPHPLC) method has been established for the simultaneous assay determination of Dolutegravir, Lamivudine and Tenofovir Disoproxil fumarate in tablet formulation. This research paper presents the detailed method development strategy and the outcome of validation challenges. The RPHPLC method was developed using a 150 x 4.6mm, 5µm C18 column, with a gradient mode using 0.1% (v/v) trifluoroacetic acid buffer and methanol, the detection was performed at 260nm. The method was validated for specificity, precision, linearity, accuracy, robustness and can be used in quality control during manufacture and for assessment of the stability samples of Dolutegravir/Lamivudine/Tenofovir Disoproxil fumarate tablets. Total elution time was about 5 min and equilibration time of about 2 min which allows analysis of more than 100 samples per day. The method reported in this study is compatible to mass spectrometry and is thus extremely useful for stability studies.