Polymer fluorescence analyses

Analysis of thermally oxidised PET by fluorescence spectroscopy has shown the presence of hy-droxylated terephthalate units [523]. These groups are formed by hydroxyl radical attack on the terephthalate units and then undergo further oxidation to produce stilbene-quinone units causing discoloration of the polymer. Fluorescence analysis has also been used to study photobleaching and photo-induced discoloration reactions in EVA formulations [22]. Fluorescence spectroscopy offers a... 

At X-ray fluorescence analysis (XRF) of samples of the limited weight is perspective to prepare for specimens as polymeric films on a basis of methylcellulose [1]. By the example of definition of heavy metals in film specimens have studied dependence of intensity of X-ray radiation from their chemical compound, surface density (P ) and the size (D) particles of the powder introduced to polymer. Have theoretically established, that the basic source of an error of results XRF is dependence of intensity (F) analytical lines of determined elements from a specimen. Thus the best account of variations P provides a method of the internal standard at change P from 2 up to 6 mg/sm the coefficient of variation describing an error of definition Mo, Zn, Cu, Co, Fe and Mn in a method of the direct external standard, reaches 40 %, and at use of a method of the internal standard (an element of comparison Ga) value does not exceed 2,2 %. Experiment within the limits of a casual error (V changes from 2,9 up to 7,4 %) has confirmed theoretical conclusions. 

By their nature, many UV absorbers are amenable to analysis by fluorimetric analysis. In many instances visible fluorescence techniques are less subject to interference by other polymer additives in a polymer extract than are UV methods of analysis. In fluorescence analysis (ex at 367 nm, em at 400-440 nm) of a PS/Uvitex OB chloroform dissolution AOs such as Ionol CP, Ionox 330, Polygard and Wingstay T/W do not interfere detection limit of 10 ppm [41]. 

Fluorescence Analysis of Irradiated PET and PET-4,41-SD Yarns. As we noted above, the fluorescence emission at 460 nm in irradiated PET polymer has been attributed to the hydroxyterephthaloyl component (2). The fluorescence spectra of irradiated (100 hours) PET homopolymer yarns and PET-4,4 -SD copolymer yarns are identical and agree with that obtained by Day and Wiles for PET film (2). 

Polymer molecular parameters were determined relative to polystyrene standards by gel permeation chromatography (GPC). The chloromethyl groups were determined by IR spectroscopy and X-ray fluorescence analysis. 

There continues to be extensive interest in latexes and micellar systems. The structure of acrylic latex particles has been investigated by non-radiative energy transfer by labelling the co-monomers with fluorescent acceptor-donor systems. Phase separations could also be measured in this way. Excimer fluorescence has been used to measure the critical micelle temperature in diblock copolymers of polystyrene with ethylene-propylene and the results agree well with dynamic light scattering measurements. Fluorescence anisotropy has been used to measure adsorption isotherms of labelled polymers to silica as well as segmental relaxation processes in solutions of acrylic polymers. In the latter case unusual interactions were indicated between the polymers and chlorinated hydrocarbon solvents. Fluorescence analysis of hydrophobically modifled cellulose have shown the operation of slow dynamic processes while fluorescence... 

In terms of general polymer luminescence there have been a number of novel reports. Colour contaminants have been identified in the manufacture of terephthalic acid as a precursor to polyester " Using fluorescence analysis the primary contaminant formed by oxidation was 4-carboxybenzaldehyde. This... 

The substitution in polymer-fluorescent dye-competitor systems has been investigated by fluorescence analysis and depending on their ability to substitute dyes competitors... 

UV-visible spectroscopy and fluorescence analysis of polymer reactions... 

Shea, K.J. Sasaki, D.Y. Stoddard, G.J. Fluorescence probes for evaluating chain solvation in network polymers. An analysis of the solvatochromic shift of the dansyl probe in macroporous styrene-divinylbenzene and styrene-diisopropenylbenzene copolymers. Macromolecules 1989, 22, 1722-1730. 

E. Kunkel, Sample preparation of elastomers and other polymers for x-ray fluorescence analysis by borax fusion, A. Anal Chem., 270 126 (1974). 

Radioactive tracers were utilized by Bueche (1962) to measure self diSusion coefficients for polymer systems above their glass-transition temperature, Tg. Price et al. (1978) described a novel approach that used scanning electron microscopy (SEM) and dispersive energy X-ray fluorescence analysis to measure the interdiffusion (D Kh cmVsec) of compatible polymer/polymer systems. Quasi-elastic light scattering (QELS) is an unusual technique due to its ability to measure both the mutual and self diffusion coefficients. Patterson et al. (1981) and Amis s. (1983) have demonstrated the apphcahon of this technique to polymeric gels. 

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