Thermal mechanical analysis TMA

Thermal-mechanical analysis (TMA) has proven a more reproducible measure of melt integrity [20]. The TMA test involves measuring the shape change of a separator under load while the temperature is linearly increased. Typically, separators show some shrinkage, then start to elongate, and finally break (see Fig. 5). 

Thermally stimulated creep (TSCr) method, 21 742-743 Thermally stimulated current spectrometry (TSC), 21 743 Thermal mass meters, 20 681 Thermal mechanical analysis (TMA), of polyester fibers, 20 21 Thermal motion, in silicon-based semiconductors, 22 237-238 Thermal noise, silicon-based semiconductors and, 22 237 Thermal oxidation, 10 77-78, 79 in VOC control, 20 683-685 Thermal oxidation rates, silicon, 22 490 Thermal oxidizers... 

Some zeolites such as AIPO4-5 (API) have a negative coefficient of thermal expansion over certain temperature ranges [230, 231]. For a zeolite formed into a pellet, one method to verify the presence of a negative coefficient of thermal expansion is by thermal mechanical analysis (TMA). For just the zeolite, powder X-ray diffraction at various temperatures can be used. Such an analysis can be of importance for identifying pellet strength or vessel containment issues. 

Major methods involved with the generation of information about thermal property behavior of materials include thermal gravimetric analysis (TGA), differential scanning calorimetry (DSC), differential thermal analysis (DTA), torsional braid analysis (TBA), thermal mechanical analysis (TMA), and pyrolysis gas chromatography (PGC). 

Figure 14.8. Thermal mechanical analysis (TMA) curve of 10FEDA/4FMPD film cured at 350°C...

The main experimental methodology used is to directly characterize the tensile properties of CNTs/polymer composites by conventional pull tests (e.g. with Instron tensile testers). Similarly, dynamic mechanical analysis (DMA) and thermal mechanical analysis (TMA) were also applied to investigate the tensile strength and tensile modulus. With these tensile tests, the ultimate tensile strength, tensile modulus and elongation to break of composites can be determined from the tensile strain-stress curve. 

In this section, some case studies will be presented on the characterization of CMP pad and slurry [17-20] using such advanced analytical techniques as dynamic mechanical analysis (DMA), modulated differential scanning calorimetry (MDSC), thermal gravimetric analysis (TGA), thermal mechanical analysis (TMA), dynamic rheometry, dual emission laser induced fluorescence (DELIF), and the dynamic nuclear magnetic resonance (DNMR). More specifically, these techniques were used to characterize (a) the effect of heat... 

The elastic modulus of the polymer can be calculated from Ea with knowledge of a from thermal mechanical analysis (TMA), when stress relaxation effects are negligible. It should also be possible to calculate crosslink density from the rubbery modulus (above Tg) by using rubber elasticity theory. 

Thermally Stimulated Current (TSC). This relatively straightforward method has been used for years as a method of thermal analysis comparable in some aspects to Thermal Mechanical Analysis (TMA). For example, TSC is able to detect many of the same transitions as seen by the mechanical methods. The advantages of TSC include its extremely high sensitivity and its low... 

Thermal mechanical analysis (TMA) was utilized by Ophir (60) to study the densifIcatlon of Epon 828 epoxy. The glass transition temperature can be easily characterized by a slope change as the resin transits from the glassy state to the rubbery state (see... 

Using dilatometer and thermal mechanical analysis (TMA), one can measure the volume of polymers as a function of temperature, as illustrated in Fig. 6.14. The step change in the slopes of the volume-temperature curve, i.e., the coefficients of thermal expansion, determines the glass transition temperature of the polymer. 

The separators nsed in Li-Ion batteries shonld have high-temperature melt integrity. The separator shonld maintain its melt integrity after shut down so that the electrodes do not touch and create a short. This helps to avoid the thermal runaway even when the cell is exposed to high temperatures. Thermal mechanical analysis (TMA) is a very good technique to measure the high-temperature melt integrity of separators. 

Figure 14.8. Thermal mechanical analysis (TMA) curve of 10FEDA/4FMPD film cured at 350°C (reproduced by permission of the American Chemical Society, from Ando et al ). ...

Thermal mechanical analysis (TMA) measures the variation in length of a sample as temperature is increased. These data can be used as a measure of the sample s coefficient of thermal expansion. TMA is good for comparing samples. TMA also measures thermal transition points by predicting the point and rate at which a compound will melt or change phase as well as determining the temperature at which blistering will occur if a molded part has not been properly post baked. 

Thermal Mechanical Analysis (TMA). TMA thermograms were obtained using a Perkin Elmer TMS-1 in the penetration mode on samples of cast resin film. The reported glass transition temperatures were identified as temperature of initial softening of the resin when heated at 10 C min under a load of... 

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