Thermogravimetry-Mass Spectrometry

Bart and co-workers [25] and others [34, 101, 163] have reviewed the application of TG-MS for the study of polymeric materials, thermoplastics, thermosets and elastomers. This thermoanalytical technique is used for the structural characterisation of homopolymers, copolymers, polymeric blends and composites and finds application in the detection of monomeric residuals, solvents, additives, (toxic) degradation products, etc. Information is 

TG-MS is an ideal technique for identifying residual volatiles in polymers. The detection of residual volatiles (and of other impurities) can often yield clues as to manufacturing processes. In many cases, such as in the determination of highly volatile materials, of residual solvents or plasticisers, use of TG-MS is requested. Specifically, there are reports on the entrapment of curing volatiles in bismaleimide laminates [145] and elastomers [48], on the detection of a curing agent (dicumylperoxide) in EPDM rubbers and of bromine flame retardants in electronic waste [50], of plasticisers such as bambuterol hydrochloride [142] or TPP and diethylterephthalate in cellulose acetate [143], on solvent extraction and formaldehyde loss in phenolic resins [164], and on the evolution of toxic compounds from PVC and polyurethane foams [146]. 

In other applications the pattern of evolution of styrene, butadiene and acrylonitrile as a function of temperature has provided a unique way for classifying different types of ABS. The loss of the antioxidant butylated hydroxytoluene (BHT) was also detected by MS preceding EVA copolymer degradation [165] BHT was identified at a concentration level of 20 ppm. Lehrle and co-workers [52] have described a successful controlled release system for the stabilisation of rubber by encapsulating efficient but rather mobile antioxidants to prevent loss from the host polymer. The performance of the controlled-release of the antioxidant BHT from alginate matrix particles was studied by means of DSC, TG and TG-MS. Polyisoprene rubber is more resistant to oxidation when protected in this way than by the equivalent concentration of unencapsulated antioxidant. 

TG-MS is ideally suited to reveal differences in pressure behaviour during thermal decomposition of materials. This has been illustrated by Mol [144] in TG-MS analysis of toluene diisocyanate (TDI) and methylene bis-4-phenol isocyanate (MDI)-based polyurethanes, where the observed greater increase in pressure for the TDI polyurethane than for the MDI derivative indicates a higher loss of low molecular weight fragments. This is not possible to deduct from the TG curves alone. Such indications are of great 

The presence of impurities and additives such as PVC as a fire retardant in polyurethanes has also been detected by means of TG-MS analysis [144], PU foam containing the flame retardant tetrakis (2-chloroethyl) ethylenediphosphate decomposes in an oxidative atmosphere at standard pressure in one rapid reaction whereby several highly toxic species are formed the TG-MS detection limit of this flame retardant was determined [166]. The most striking fact is the very early generation of vinylchloride from the flame retardant, while HCN is produced at much higher temperatures. 

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Fillman, L. M., and T ang, S. C., Thermal Decompositon of Metal Carbonyls A Thermogravimetry-Mass Spectrometry Study, ThermochimicaActa, 75 71-84 (1984)... 

Thermoanalysis methods such as pyrolysis-gas chromatography-mass spectrometry [GC-MS] and thermogravimetry mass spectrometry have been used to characterise hydrocarbon sludges from petrochemical plants and polluted soils [26,27]. In combination with conventional extraction and supercritical fluid extraction followed by [ GC-MS ], over 100 constituents were identified in samples. White et al. [28] also applied pyrolysis-[GC-MS] to the determination of hydrocarbons and showed that the analysis can be complicated by the presence of natural organic matter. White [28] inferred the presence of biogenic compounds in Alaskan soil. 

Faix O, Jakab E, Till F, Szekely T (1988b) Study on low mass thermal degradation products of milled wood lignins by thermogravimetry-mass-spectrometry Wood Set Technol 22 323-334... 

Follow-up characterization of the volatiles initially analyzed by TGA could also be conducted. Confirmation of the volatiles may be accomplished using one of several techniques thermogravimetric-infrared (TG-IR) spectroscopy, gas chromatography (GC), or thermogravimetry-mass spectrometry (TG-MS). These techniques may be able to qualitatively and quantitatively determine the content and identification of the solvents present in the material. Additionally, Karl Fisher titrimetric assays may be utilized to quantitate the water content in the material. 

Thermogravimetry/mass spectrometry was used to determine adsorptive capacity of several commercially available activated carbons produced from coal, coconut, and petroleum pitch precursors. The range of their N2 BET surface areas was between 400 to 2000 m /g. Although, carbons with high adsorption capacity contained similar C, N, and O contents, proximate analyses, surface areas and micropore volumes, no significant correlations were found between chemical and physical properties and the NO, adsorptive capacity. One possibly important characteristic of the carbons correlated with NO, adsorption capacity was specific and narrow pore size distribution with an effective pore diameter of 0.56 nm. 

Applying conventional (thermogravimetry TG Differential thermal analysis DTA evolved gas detection EGD) and combined (thermogravimetry-mass spectrometry TG-MS) techniques, the pCD inclusion complexes with thymol and Lippia sidoides Cham EO (LsCEO) extract produced by kneading method were characterized. Its formations were detected through released gas... 

Thermogravimetry-mass spectrometry was done with a Perkin Elmer TAS 2 TGA connected by a capillary transfer line to a Hewlett Packard mass selective detector. A heating rate of 40 C7min was used so that the volatiles would rapidly desorb from the sample. Helium was used as a carrier gas at a pressure of 40 psi. The time traces of water and NMP were done at mass to charge ratios of 18 and 99 respectively. 

Although water is known as a natural plasticizer for many polar polymers such as nylon, polyester resins, and cellulosic polymers, similar behavior for polyacrylamide and poly(acrylamide-co-acrylic acid) has not been investigated. In this study, the effect of water content (and/or thermal history) on the Tg s of acrylamide-based pol3 TOers was studied by Differential Scanning Calorimetry (DSC), Thermogravimetry (TG), Thermomechanical Analysis (TMA), and Simultaneous Thermogravimetry - Mass Spectrometry (TG/MS). 

This study combines a thermal analysis technique -thermogravimetry with atmospheric pressure chemical ionization mass spectrometry and applies the combined technique to the third question. The literature contains references relating to the analysis of styrene butadiene copolymers using thermal analysis techniques (1-5). Pyrolysis - mass spectrometry (5) and vacuum thermogravimetry - mass spectrometry (7) have also been used to investigate polymers such as polystrene and styrene butadiene rubber. 

An interesting procedure in forensic paint analysis, however, is thermogravimetry-mass spectrometry (TG-MS), determining simultaneously TG curve and its first derivative, total ion current versus the TG temperature, single ion currents for selected molecular fragments versus TG temperature, and determination of the pigment/volume concentration of... 

Raemaekers KGH and Bart JCJ (1997) Application of simultaneous thermogravimetry - mass spectrometry in polymer analysis. Thermochimica Acta 295 1-58. 

Perng [95] used thermogravimetry-mass spectrometry (TG-MS) under helium to investigate in detail, the nature of the decomposition products produced when PPS is heated to temperatures up to 700 °C. 

Raemaekers, K.G.H., Bart, J.C.J. (1997) Applications of simultaneous thermogravimetry-mass spectrometry in polymer analysis. Thermochim. Acta, 295,1-58. 

Keen and co-workers [20] used EGA to monitor the evolution of additives from rubber and polymers in order to evaluate the effectiveness of encapsulated BHT antioxidant from polyisoprene. The technique involves the coupling of a thermogravimetry mass spectrometry with oxidative DSC. 

Bron M, Eiechter S, Bogdanoff P, Tributsch H (2002) Thermogravimetry/mass spectrometry investigations on the formation of oxygen reduction catalysts for PEM fuel cells on the basis of heat-treated iron phenantroline complexes. Euel Cells 2 137-142... 

The mechanism of the decomposition reaction into metal fluorides has not been elucidated so far. In the first place, metal trifluoroacetates themselves have been relatively less studied among the salts of carboxylic acids. Synthesis and properties of only a few metal trifluoroacetates have been reported (Killings, 1974 Khristov, 1998 Tada, 1999). Thermogravimetry-mass spectrometry (TG-MS) analysis has been carried out to examine the deconposition reaction oflanthanum trifluoroacetate (Eujihara, 2000b). The reaction suggested is... 

E.L. Charsley, S.B. Warrington, G.K.Jones and A.R. McGhie. bttematiomd Laboratory 1990 March/April 13-19. Thermogravimetry - Mass Spectrometry using a simple Capillary lnt ace. 

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