Quantitative analyses, polymer

B. O. Cullity and S. R. Stock, Elements of X-Ray Diffraction , 3rd Edition, Prentice Hall, Upper Saddle River, 2001, Excellent treatment of powder methods in general. Includes phase-diagram determination, polycrystalline aggregates, polymers, quantitative analysis and stress analysis. 

Wang, M. Dykstra, T.E. Lou, X. Salvador, M.R. Scholes, G.D. Winnik, M.A. Colloidal CdSe nanocrystals passivated by a dye-labeled multidentate polymer Quantitative analysis by size-exclusion chromatography. Angew. Chem. Int. Ed. 2006,45 (14), 2221-2224. 

Key words extrusion monitoring NIR polymer quantitative analysis... 

Principles and Characteristics As already indicated by Lattimer et al. [201], mass spectrometry is usually employed only for qualitative analysis of additives in polymers. Quantitative analysis is frequently performed by employing techniques other than mass spectrometry. Nevertheless, a great variety of ionisation modes and mass spectrometric techniques (hyphenated or not) have been tried on polymer/additive analysis. In this Chapter we will examine the quantitative performance of some of these techniques, in particular FD-MS, FAB-MS, LSIMS, DCI-MS", DT-MS, MALDI-ToFMS, GC-MS, LC-MS", TG-MS, TPPy-MS and PyGC-MS. 

Computer modelling provides powerful and convenient tools for the quantitative analysis of fluid dynamics and heat transfer in non-Newtonian polymer flow systems. Therefore these techniques arc routmely used in the modern polymer industry to design and develop better and more efficient process equipment and operations. The main steps in the development of a computer model for a physical process, such as the flow and deformation of polymeric materials, can be summarized as ... 

H. J. Goites, G. E. Bormett and J. D. Graham, Quantitative polymer additive analysis by multidimensional cliromatography using online coupled microcolumn size exclusion cliromatography as a preliminary separation , 7. Microcolumn Sep. 4 51 - 57 (1992). 

In the identification of different polymorphs in polymers the FTIR technique presents, with respect to the diffraction techniques, the advantage of easier and more rapid measurements. In particular, the high speed of the measurements allows to study the polymorphic behavior under dynamic conditions. As an example let us recall the study of the transition from the a toward the P form of PBT induced by tensile stresses, evaluated by quantitative analysis of the infrared spectra [83],... 

The refractive index detector, in general, is a choice of last resort and is used for those applications where, for one reason or another, all other detectors are inappropriate or impractical. However, the detector has one particular area of application for which it is unique and that is in the separation and analysis of polymers. In general, for those polymers that contain more than six monomer units, the refractive index is directly proportional to the concentration of the polymer and is practically independent of the molecular weight. Thus, a quantitative analysis of a polymer mixture can be obtained by the simple normalization of the peak areas in the chromatogram, there being no need for the use of individual response factors. Some typical specifications for the refractive index detector are as follows ... 

Small solid seuaples can be analyzed directly by dynamic headspace sampling using a platinum coil and quartz crucible pyrolyzer and cold trap coupled to an open tubular column (341,369,379). This method has been used primarily for the analysis of mineral samples and of additives, catalysts and byproducts in finished polymers which yield unreliable results using conventional headspace techniques owing to the slow release of the volatiles to the headspace. At the higher temperatures (450-1000 C) available with the pyrolyzer the volatiles are more readily and completely removed from the sample providing for quantitative analysis. 

IR Identification of mbber, polymer type (quantitative analysis), additives... 

It is quite clear from Schemes 2.1-2.5 that in rubbers polymer identification and additive analysis are highly interlinked. This is at variance to procedures used in polymer/additive analysis. The methods for qualitative and quantitative analysis of the composition of rubber products are detailed in ASTM D 297 Rubber Products-Chemical Analysis [39]. 

Several qualifying features for polymer extract analysis are summarised in Table 2.11. Quantitative separation of polymer and (thermolabile and/or volatile) additives without decomposition of the analyte(s) is difficult for thermoplasts, but even more difficult for... 

Applications Conventional GC is a workhorse in the qualitative and quantitative analysis of polymer additives in complex mixtures and has found numerous applications. Both GC and auxiliary techniques are particularly useful for characterisation of (semi)volatile constituents and additives ranging from gases to hydrocarbon waxes (fatty acids and their... 

Applications Chromatography is a preferred technique for additive analysis as it allows both separation of additives in a mixture and subsequent quantitation. Despite the developments in GC, this technique cannot separate many polymer additives. Even with its lower efficiency in comparison to GC, HPLC is today one of the cornerstones in a polymer additive laboratory. Judging by the number of publications in recent years, HPLC is first among analytical methods for additives (confirmation/identification/quantification). Most additives may be analysed by HPLC if they can be dissolved in an HPLC solvent and absorb UV light. Typical polymer/additive analyses are carried out using LPE followed by HPLC with UV or RI detection [605-611]. Verification of the identity of an analyte is then based on a combination of retention time, UV and RI evidence. RPLC is used most frequently for polymer/additive analysis, but normal-phase and SEC are also used. Consequently, techniques for additive analysis by HPLC are legion. 

Normal-phase chromatography is still widely used for the determination of nonpolar additives in a variety of commercial products and pharmaceutical formulations, e.g. the separation of nonpolar components in the nonionic surfactant Triton X-100. Most of the NPLC analyses of polymer additives have been performed in isocratic mode [576]. However, isocratic HPLC methods are incapable of separating a substantial number of industrially used additives [605,608,612-616], Normal-phase chromatography of Irgafos 168, Irganox 1010/1076/3114 was shown [240]. NPLC-UV has been used for quantitative analysis of additives in PP/(Irganox 1010/1076, Irgafos 168) after Soxhlet extraction (88%... 

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