Rubber GC analysis of bound

It is of interest to examine the development of the analytical toolbox for rubber deformulation over the last two decades and the role of emerging technologies (Table 2.9). Bayer technology (1981) for the qualitative and quantitative analysis of rubbers and elastomers consisted of a multitechnique approach comprising extraction (Soxhlet, DIN 53 553), wet chemistry (colour reactions, photometry), electrochemistry (polarography, conductometry), various forms of chromatography (PC, GC, off-line PyGC, TLC), spectroscopy (UV, IR, off-line PylR), and microscopy (OM, SEM, TEM, fluorescence) [10]. Reported applications concerned the identification of plasticisers, fatty acids, stabilisers, antioxidants, vulcanisation accelerators, free/total/bound sulfur, minerals and CB. Monsanto (1983) used direct-probe MS for in situ quantitative analysis of additives and rubber and made use of 31P NMR [69]. 

The advantage of the Py-GC-MS method over other methods for measuring styrene content of SBR copolymer is its relatively easy use for analysis of clear polymers as well as polymers containing process oils, fillers, and carbon black, and even cured rubbers. Moreover, the percent bound styrene obtained by this technique is not affected by changes of copolymer microstructure. Results of this work clearly show that the percentage of styrene obtained by this technique correlates very well with the results obtained by other methods. 

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