Rubbers, analysis

Report 139 Rubber Analysis - Polymers, Compounds and Products, M.J. Forrest, Rapra Technology Ltd. 

Analysis of natural rubber Analysis of synthetic mbber Oils-characterisation-CC Rubber chemicals-Infrared Rubber chemicals-Ultraviolet Antidegradant-TLC Rubber-Pyrolysis GC Rubber identification by IR spectrophotometry Ct2, Br2, I2 by oxygen flask... 

Table 2.4) or proprietary test methods. Forrest [38] has listed 94 international rubber analysis standards (ISO) and 20 ISO standards in preparation referring to latices, carbon-black-filled compositions, raw and compounded rubbers. 

The conventional approach to rubber analysis employed by BFGoodrich (and others) is shown in Scheme 2.1. Pausch [82] has reviewed the analytical approach utilised for determining the AO composition. Pausch et al. [70] have initially experimented with direct compound analysis using ATR-FTIR, NMR, PyMS, and TGA and have subsequently focused on a wide... 

The logical approach to problem solving for rubber analysis at Polysar Ltd was described by Chu [73] (cf. Schemes 2.4 and 2.5). Systematic analysis involves sampling, elimination of interference and measurement. Methods employed include chromatography (GC, HS-GC, HPLC, SEC, IC), spectroscopy (AAS, UV/VIS, IR, NMR), MS, microscopy and thermal analysis. The specific role of each of these techniques for the analysis of rubber compounds with or without... 

Analytical techniques used in troubleshooting and formulation experimentation available to the rubber compounder were reviewed [90]. Various textbooks deal with the analysis of rubber and rubber-like polymers [10,38,91]. Forrest [38] has illustrated the use of wet chemistry, spectroscopic, chromatographic, thermal, elemental and microscopy techniques in rubber analysis. 

Applications Although Soxtec combines the best qualities of reflux and Soxhlet extractions up to now fairly little evidence has been reported concerning the efficacy of this system for polymer and rubber analysis. Nevertheless, it appears that oligomers and other reaction residues, softeners, antioxidants (e.g. BHT) and several other additives used to modify polymers are easily extracted from PVC, PP, PE, PS, rubber and many other polymeric materials. Also, some leading international plastic, rubber and packaging companies have made Soxtec an integral part of their quality control routines. Some application examples where Soxtec has proved successful are [148] ... 

This technique is used to detect metals in rubber analysis. 

GC is used in rubber analysis to obtain polymer type information by use of a pyrolysis approach, also to identify some additives. 

This is used to identify the polymer and additive types in rubber analysis. 

This is used in rubber analysis. HPLC combined with a mass selective detector enables unknown samples to be analysed. 

Another example of rubber analysis is the determination of vinyl-butadiene in SBR. A PA-FTIR spectrum of a high-vinyl content SBR is shown in Figure 2.10. This determination by mid-IR methods invariably involves the use of the 910 cm"1 band due to the wagging motion of the pendent vinyl group of 1,2-butadiene. 

Wyden, H. Widmann, G. Skrabka, T. Rubber analysis using the thermobalance TGA850. Elastomery 1999, 5 (4), 34-37. 

This article describes the different stages of natural rubber analysis by SEC, concentrating on the points that distinguish natural rubber from other more conventional polymers. 

Belsito, D.V. (1990) Contact urticaria caused by rubber. Analysis of seven cases. Dermatol Clin. 8, 61-66 Questions whether increased demand for latex may have decreased quality with more allergens leachable. 

S. Tuampoemsab, Control of the Degradation of Natural Rubber Analysis and Application of Naturally Occurring Anti- and Pro-Oxidants in Natural Rubber, PhD thesis, Mahidol University, Thailand, 2008. 

Fourier transform infrared spectroscopy (FTIR) has emerged as a valuable tool for rubber analysis. Siesler monitored the onset, progress and decay of strain-induced crystallization of a sulfur-cured NR during a cyclic experiment. The infrared absorbance of NR at 1126 cm assigned to C-CH3 in-plane deformation vibration is a band sensitive to crystallinity. A thickness reference band was taken to be the 1662 cm one assigned to v(C=C) stretching. The ratio of the absorbance bands at 1126 cm and 1662 cm revealed the reversible nature of strain-induced crystallization of NR. 

More recently, Lattimer et al. [2,678] have used direct methods of qualitative rubber analysis. Various direct single-stage mass spectrometric methods were found to be effective for identifying organic additives in rubber. Tandem mass spectrometry (MS/MS) increases the specificity and sensitivity of detection and identification of additives in direct rubber compound analysis [431,744], Again, Py-FIMS turned out to be a good technique for analysis of both the organic additives and rubber components in the same experiment [675], Results of these studies have been summarised in a review paper on rubber compound analysis [745],... 

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