Polymers thermogravimetry

Thermal analysis iavolves techniques ia which a physical property of a material is measured agaiast temperature at the same time the material is exposed to a coatroUed temperature program. A wide range of thermal analysis techniques have been developed siace the commercial development of automated thermal equipment as Hsted ia Table 1. Of these the best known and most often used for polymers are thermogravimetry (tg), differential thermal analysis (dta), differential scanning calorimetry (dsc), and dynamic mechanical analysis (dma). 

ANALYSIS OF PEROXIDE GROUPS IN POLYMERS BY CHROMATOGRAPHY AND THERMOGRAVIMETRY... 

Thermal analysis helps in measuring the various physical properties of the polymers. In this technique, a polymer sample is subjected to a controlled temperature program in a specific atmosphere and properties are measured as a function of temperature. The controlled temperature program may involve either isothermal or linear rise or fall of temperature. The most common thermoanalytical techniques are (1) differential scanning analysis (DSC), (2) thermomechanical analysis (TMA), and (3) thermogravimetry (TG). 

Each sample was evaluated by thermogravimetry to determine if the thermal stability could be enhanced by removing some residual cobalt chloride. The BTDA-ODA polyimide film thermal stability is reduced about 50 C due to the cobalt chloride dopant. Soa)cing or extraction with water has no positive effect on the thermal stability whereas soxhlett extraction with DMAc severely degrades the polymer stability. For the BDSDA-ODA polyimide films the incorporation of cobalt chloride also reduces the bul)c polymer thermal stability. Soa)cing this film in water for 24 hours, however, increased the bul)c thermal stability slightly from 512 to 532 C. 

The thermal behavior of the hyperbranched polymer 7, as well as that of the related tetra- and octanuclear dendrimers 1 and 2, was examined by thermal gravimetric analysis (TGA) and derivative thermogravimetry (DTG). The samples were heated at a ramp rate of 10 °Cymin under nitrogen atmosphere in the tenqierature range 25-8(K) °C. The major decompositions occur between 340 and 540 °C for the tetranuclear 1, and between 370 and 520 °C for the octanuclear 2, whereas for polymer 7 a faster rate of weight loss is observed at a higher (480 and 560 C) temperature range. The thermal stability of the network dendrimeric material 7 is... 

In the present study, PU s containing lignin were investigated with reference to thermal stability, which is one of the basic thermal properties of polymers. Thermal degradation of PU s which were obtained from solvolysis lignin was studied using thermogravimetry (TG). The inflammability of... 

This route was described more or less simultaneously by Karasz et al. 235) and by Murase et al.236). The precursor polymer is typically prepared by reaction of the appropriate bis(chloromethyl)arylene compound with dimethylsulfide in a polar solvent237,238). The product is a water-soluble polymer which can be cast to give thin films. Elimination of hydrochloric acid and dimethyl sulfide takes place on heating the film in the range 200 to 300 °C and can be monitored by thermogravimetry and by the development of colour and conductivity 239. Poly(p-phenylene vinylene), prepared by the precursor route, can be doped to much higher conductivities than the conventionally synthesised polymer. 

A procedure based on condensation with phenol and paraform (used as formaldehyde source) was developed to convert spent UNEX solvent (CCD, PEG-400, Ph2-CMPO, and FS-13) into a solid infusible resin for disposal. The resulting material is insoluble in aqueous alkali and acidic solutions and organic solvents. Incorporation of FS-13 in the cross-linked polymer was confirmed by physicochemical methods. Resistance of the cured resin to high temperatures was proven by thermogravimetry... 

In addition to routinely used methods, such as elemental analysis, IR and UV-vis-NIR spectra, thermogravimetry-differential thermal analysis (TG-DTA), single-crystal X-ray diffraction, and gas adsorption, there are some important characterization methods for coordination polymers. 

Thermal analysis is a group of techniques in which a physical property of a substance is measured as a function of temperature when the sample is subjected to a controlled temperature program. Single techniques, such as thermogravimetry (TG), differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), dielectric thermal analysis, etc., provide important information on the thermal behaviour of materials. However, for polymer characterisation, for instance in case of degradation, further analysis is required, particularly because all of the techniques listed above mainly describe materials only from a physical point of view. A hyphenated thermal analyser is a powerful tool to yield the much-needed additional chemical information. In this paper we will concentrate on simultaneous thermogravimetric techniques. 

Schonherr [43] has described the combination of decomposition in a thermogravimetry oven and FTIR spectroscopy for the identification of base polymers in elastomers, as exemplified for nitrile rubber, and has presented infrared spectra for decomposition products of various rubbers. The same author [36] studied use of the integrated TG-FTIR system for the identification of sixteen vulcanised rubbers in mechanical goods reporting the characteristic infrared spectra of the degradation products at temperatures ranging from 334 °C to 635 °C. 

Plastics-Thermogravimetry(TG) of polymers—Part 2 Determination of activation energy, BS ISO 11358-2 2005. 

Howell, B. A. The application of thermogravimetry for the study of polymer degradation. Thermochimica... 

Thermogravimetry is a technique that measures the weight change of a sample as a function of temperature or time (time is suitable only when thermal analysis is performed at specified constant temperature increments). The solid or liquid sample is heated or cooled at a selected rate or isothermally maintained at a fixed temperature. TG is used to measure degradation, oxidation, reduction, evaporation, sublimation, and other heat-related changes occurring in polymers. 

A kinetic model of the physical process of loss of plasticiser di-(2-ethylhexyl)-phthalate from plasticised PVC foil is developed. Experimental investigations are carried out using isothermal thermogravimetry in the temperature range of 120-150 deg.C. The thickness of the foil is 0.1 mm and the amount of the plasticiser in the plasticised polymer is 10-40%. The kinetic parameters... 

Thermogravimetry (TG) or thermogravimetric analysis (TGA). In this technique, the mass of a sample is followed as a function of temperature or time. The amount and rate of mass change with temperature or time in a controlled atmosphere are obtained. Such information can tell us about thermal stability as well as the compositional profile of a variety of elastomers and polymers. It is an excellent quantitative technique but qualitatively there may be some doubt as to what material is lost during heating. 

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