Thermal Analysis System TGA 2
Thermal Analysis System TGA/DSC 3+
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Brochure: TGA 2

Brochure: TGA 2

Thermogravimetry (TGA) is a technique that measures the change in weight of a sample as it is heated...

Soluções de Automação de Análise Térmica

Automação de Análise Térmica

Saiba como nossas soluções de automação de análise térmica podem reduzir o esforço e melhorar a efic...

Brochure: STARe Excellence Software

Brochure: STARe Excellence Software

Thermal analysis is a well-established analytical method that is widely used in many different field...

Datasheet: TGA-EGA

Datasheet: TGA-EGA

TGA-MS, TGA-FTIR, TGA-GC/MS and TGA-Micro GC/MS are powerful techniques that yield both quantitative...

Brochure: TGA-IST16-GC/MS System

Brochure: TGA-IST16-GC/MS System

Thermogravimetric analysis combined with gas chromatography and mass spectrometry (TGA-GC/MS) is now...

Datasheet: TGA-Sorption System

Datasheet: TGA-Sorption System

The TGA-Sorption System allows you to precondition samples at temperatures up to 150 °C and to incre...

Datasheet: ACC Calibration Datasheet for TGA Microbalances

Datasheet: ACC Calibration Datasheet for TGA Microbalances

ACC quantifies the performance of your TGA micro- or ultra-microbalance and determines the measureme...

Treinamentos On-line de Análise Térmica

Treinamentos On-line de Análise Térmica

Temos o prazer de oferecer 4 treinamentos on-line pela internet sobre interpretação de curvas de DSC...

Análise Termogravimétrica (TGA)

Análise Termogravimétrica (TGA)

Neste webinar, vamos discutir os princípios básicos da TGA/DSC e apresentar algumas aplicações inter...

TGA-Sorption analysis webinar

Webinar – TGA-Sorption Analysis – Principles and Applications

TGA-Sorption analysis characterizes drying processes, as well as sorption or adsorption behavior

Evolved gas analysis

Webinar – Evolved Gas Analysis

Evolved gas analysis complements TGA by characterizing decomposition products and volatiles.

What is TGA? / What is a thermogravimetric analysis?

Thermogravimetric analysis (TGA) is a technique used to study the thermal properties of materials. It involves measuring the weight change of a sample as it is subjected to controlled heating or cooling in a controlled atmosphere. By monitoring the weight loss or gain of the sample over a range of temperatures, TGA can provide information about the composition, thermal stability, decomposition, volatilization, and other thermal properties of a material.

TGA is widely used in materials science, chemistry, and engineering to understand the behavior of polymers, ceramics, metals, and other materials under different thermal conditions.

For more information, we recommend watching our free Fundamentals of TGA Analysis webinar.

How do you interpret a TGA curve?

TGA curve

A TGA curve visually depicts a sample's mass change (y-axis) as temperature increases (x-axis). To interpret a TGA curve, focus on these key elements:

  • Weight loss events: Dips in the curve signify mass loss, potentially due to evaporation, decomposition, or the release of bound substances within the sample.
  • Temperature of events: The temperature at which significant weight loss occurs offers clues about the decomposing component.
  • Rate of weight change: The slope of the curve reflects the rate of mass change. A steeper slope indicates a faster decomposition process.

TGA curve interpretation is often the most difficult part of the analysis. To help you correctly interpret your measurement curves, we provide a variety of web-based training courses dedicated to curve interpretation and result analysis. Register for our Thermal Analysis eTraining Courses.

For example, the curve in the diagram shows a single mass loss step of pure polypropylene as it is heated in an inert atmosphere.

What is the principle of thermogravimetric analysis?

The working principle of thermogravimetric analysis (TGA) involves continuously monitoring the mass change of a sample while it is heated, cooled, or held at a constant temperature in a controlled environment. A high-precision balance measures the sample's change in weight. The data, plotted as mass versus temperature, provides insights into the material's behavior as the temperature program progresses, including stability and decomposition.

How does thermogravimetric analysis work?

Thermogravimetric analysis works by precisely measuring the weight change of a sample as it is subjected to a controlled temperature program in a controlled atmosphere. The sample is placed in a crucible, which is then placed on a built-in microbalance within the furnace. As the temperature increases, the material may undergo changes that cause a change in weight. The atmosphere can be switched between inert and oxidizing, depending on the experiment. Evolved gases can be transported into connecting equipment for further analysis, to help identify the sample composition.

As the thermogravimetric analyzer continuously monitors the weight change, the data is plotted as weight vs. temperature (or time) to create a TGA curve. This curve reveals key information about the material's behavior at different temperatures.

How do you analyze TGA data?

TGA data typically appears as a weight change (% or mg) vs. temperature (°C) or time (min) curve. Analyzing the curve involves the following steps:

  • Identify weight loss/gain events: Look for significant changes or steps in the curve, indicating weight loss (e.g. due to vaporization, pyrolysis or thermal decomposition in an inert atmosphere, or burning in an oxidative atmosphere) or gain (e.g. absorption). Multiple weight loss steps at different temperatures indicate the thermal decomposition of different components.
  • Correlate with temperature: The temperature at which these events occur can provide clues about material properties like decomposition temperature and composition.
  • Reference materials: Compare your data with the known behavior of similar materials.

What type of analysis is TGA?

Thermogravimetric analysis (TGA) is a type of thermal analysis. This category of techniques studies how materials behave as they are subjected to a controlled temperature program in a defined atmosphere.

What are the applications of thermal gravimetric analysis and what is it used for?

The applications of thermal gravimetric analysis encompass a wide range of industries. They involve analyzing the behavior of different materials as a function of temperature, including polymers, metals, chemicals, ceramics, and pharmaceuticals. By measuring mass changes due to decomposition, evaporation, or absorption, thermal gravimetric analysis reveals material composition, thermal stability, and moisture content.

TGA is most frequently used to investigate processes such as vaporization, composition, and decomposition behavior. Evolved gases can be analyzed using hyphenated techniques such as TGA-MS, TGA-FTIR and TGA-GC/MS.

What are the advantages of thermal gravimetric analysis?

Due to its unique advantages, thermal gravimetric analysis (TGA) is a powerful tool used to characterize materials across many industries. It requires minimal sample preparation and uses only milligrams of material, making it ideal for precious or limited samples. Additionally, its high sensitivity allows for detecting minute mass changes, providing detailed information about decomposition processes.

TGA's versatility extends to diverse fields, including batteries and electronics, polymers, renewable energy components, composites, automotive parts, tires, foods, pharmaceuticals, and petrochemicals. A single test offers a wealth of data, including thermal stability, decomposition behavior, moisture content, and identification of volatile components.

The advantages of our TGA instruments include the world's best METTLER TOLEDO micro and ultra-micro balances, with internal calibration ring weights for unbeatable accuracy. You can calibrate the balance with external weights and measure small or large samples with up to 50 million resolution points, detecting weight changes in 0.1 µg increments. No other TGA offers this level of precision and range.

How do you determine a chemical by thermal gravimetric analysis?

While thermal gravimetric analysis is a valuable tool for material analysis, it cannot directly identify a specific chemical. It measures weight changes during heating or cooling, revealing thermal behavior but not the exact chemical makeup.  However, weight-loss curves can be compared with reference curves of a known material, and when TGA is combined with other complementary techniques and information, such as evolved gas analysis, thermal gravimetric analysis can be a valuable aid in chemical determination.

What information do we obtain from thermogravimetric analysis?

You might be asking, “So what does thermogravimetric analysis measure?” TGA provides a wealth of measurement information about a material's behavior under changing temperatures by measuring its mass change. Here's what kind of information TGA can provide:

  • Thermal stability: TGA helps in determining a material's decomposition temperature. As the temperature increases, the sample may break down, releasing gases and losing mass. This occurrence indicates the material's thermal stability.
  • Composition: TGA can help identify different components in a sample. If a material has multiple components with varying decomposition temperatures, the TGA curve will show distinct mass-loss events at those temperatures.
  • Moisture content: TGA can be used to measure the amount of moisture (water) present in a sample. As the sample is heated, the water evaporates, causing a measurable mass loss.
  • Adsorbed species: TGA can also reveal the presence of adsorbed substances on a material's surface. These adsorbed species can evaporate upon heating, resulting in a mass change.
  • Reaction processes: TGA can be used to study chemical reactions that occur within a material upon heating. The mass change can indicate the consumption or release of reactants or products during the reaction.

What is the difference between DSC and TGA?

DSC and TGA are two different thermal analysis techniques that analyze different aspects of a material's response to a controlled temperature program. TGA measures mass change by detecting weight loss or gain as a function of temperature. DSC measures heat flow into or out of the sample as a function of temperature.

What is the difference between TGA and DTA?

TGA and DTA are both thermal analysis techniques that provide information in different ways. TGA measures the mass change of a sample as it is subjected to a controlled temperature program. DTA measures the temperature difference between a sample and a reference material to reveal if the sample is absorbing or releasing heat during thermal events like melting or decomposition.

What are the limitations of thermogravimetric analysis?

Here are some limitations of thermogravimetric analysis (TGA):

  1. Limited to weight changes: TGA only provides information about a sample's change in mass as it is heated, cooled, or held isothermally at the same temperature. It does not directly identify specific components, and some training is required to analyze a TGA measurement curve.
  2. Interpretation challenges: Data interpretation can be complex. Factors such as heating rate and sample size can influence the results.
  3. Only applicable to weight-changing processes: TGA can't analyze processes that don't involve mass change, like melting or solid-state transitions.
  4. Limited sample size: Typically, only small sample amounts (milligrams) are used in TGA, which may not represent the bulk material.