The control of the energy transfer (FRET) in a novel bischromophoric styryl(pyridinium) dye bearing two different crown ether residues is presented.
A new confirmatory method for simultaneous determination of bisphenol diglycidyl ether residues (BADGE, BADGE·H2O, BADGE·2H2O, BADGE·H2O·HCl, BADGE·HCl, BADGE·2HCl, BFDGE and BFDGE·2HCl) from canned food has been developed.
Monosulfonation of copolymers prepared using mixtures of hydroquinone and durohydroquinone occurred as expected at the hydroquinone residues, but again some sulfonation of phenylene ether sulfone residues occurs and there may be other complications.
The bis-phenol residues in the homopolymers prepared using methylhydroquinone or its dimethyl analogue were monosulfonated completely, but with the homopolymer from trimethylhydroquinone this sulfonation was not complete and it appears that sulfonation of phenylene ether sulfone residues may also occur.
After the solvent was decanted, the polymer was washed with 2 volumes of fresh ether, then the residue was dried under vacuum for 2 days before it was formed into a stock of 100 mg/ml in DMSO, which was stored at −20 °C.
Following ether evaporation, the residue was solubilised in ethyl acetate and analysed by GC-MS [ 25].
The extract was concentrated at low temperature to remove petroleum ether; the oily residue was collected and dried.
Excess methyl iodide was removed by extraction with ether, and the residue was cautiously acidified with 2.0 M HCl until evolution of CO2 ceased.
The resulting FAMEs and MAMEs were dissolved in diethyl ether and insoluble residues removed by centrifugation.
On treatment of the residue with ether (5 ml), a colourless salt separated, which was cyclised as described above.
