Understanding Thermogravimetric Testing of Plastics

Thermogravimetric analysis (TGA) can offer a lot of information about how materials react to heat. As a thermal analysis technique, its purpose is to examine materials and show any changes occurring thanks to the alterations in temperature. This includes any weight loss. By understanding these reactions, there is the potential to learn more about a material’s characteristics and behaviors, such as at what temperature thermal decomposition occurs or any solid-gas reactions.

The more that is understood about a material’s properties, the easier it is to find its best application. This information is essential for industries that need specific materials with certain characteristics. Although thermogravimetric testing is used to see what happens when a sample is heated, it also acts as a means of control. It can regulate the quality of materials, providing insights into any heat-related effects. That way there is the assurance that a product will work as intended.

One material that can be examined through thermogravimetric testing is plastic. Join us as we undertake a deep dive into thermogravimetric testing and how it can be used to uncover the properties of plastics.

How Does Thermogravimetric Testing Plastics Work?

The thermogravimetric testing of plastics involves heating a small sample of plastic material. Then the mass changes are measured as the temperature increases. This technique provides valuable information about the thermal stability and composition of plastics, including the presence of fillers, plasticizers, and other additives. The data obtained from thermogravimetric testing can be used to predict the material’s behavior in different environmental conditions, such as exposure to heat, which is crucial for applications where thermal resistance is essential.

Ultimately, the core principle behind TGA is straightforward. As the temperature of the plastic sample increases, various components may begin to decompose or volatilize. This leads to a measurable decrease in the sample’s mass. The rate of heating, atmosphere (inert or oxidative), and the sample size can be varied to simulate different conditions. They can also be used to target specific decomposition mechanisms.

Key Applications of Thermogravimetric Testing Plastics

• Thermal Stability: Thermogravimetric testing provides a clear indication of the temperature ranges within which a plastic material remains stable. This makes it invaluable for determining operational and failure temperatures.
• Composition Analysis: By analyzing the mass loss at specific temperature intervals, the composition of plastic materials, including the presence of fillers, reinforcements, and plasticizers, can be inferred.
• Decomposition Kinetics: The analysis from thermogravimetric testing allows for the study of decomposition mechanisms and kinetics, which is essential for understanding how plastics degrade under thermal stress.
• Moisture and Volatile Content: TGA is adept at measuring the moisture and volatile content in plastics. This can significantly affect their mechanical properties and processing behavior.

Interpretation of TGA Curves

The output of thermogravimetric testing is typically a thermogram. A thermogram is a plot of mass loss (or rate of mass loss) against temperature or time. The key features of a thermogram include:

• Onset of Degradation: The temperature at which significant mass loss begins, indicating the thermal stability threshold.
• Major Mass Loss Events: Peaks or steep sections of the curve that represent the decomposition of the main polymer chains. It can also demonstrate the evaporation of major components.
• Residue: The final mass percentage remaining after the test, often indicative of fillers or non-volatile residue.

Best Practices for the Thermogravimetric Testing of Plastics

• Sample Preparation: Uniform, representative samples of the plastic material are crucial for accurate TGA.
• Atmospheric Control: Thermogravimetric testing should be conducted under appropriate atmospheric conditions (inert or oxidative) to mimic the intended application environment.
• Heating Rate: The heating rate should be chosen based on the goal of the analysis. Slower rates can provide clearer insights into decomposition mechanisms, while faster rates may be used for quality control purposes.

Thermogravimetric Testing Technology: The XRTGA-1100

At XRF Scientific, we are committed to empowering researchers and industry professionals with cutting-edge analytical techniques and instruments. Our dedication to advancing materials science research is reflected in our continuous efforts to provide state-of-the-art equipment for thermogravimetric testing.

With the XRTGA-1100, we offer a robust solution tailored for precise, reliable thermogravimetric measurements, facilitating enhanced material innovation. This device can be used with heats reaching 1100°C. Moreover, it has a carousel that contains 30 places for your materials. That way you can be as efficient as possible with your tests.

Thermogravimetric Testing Can Offer Insights on Plastics

Learning about how plastics react under differing heats provides a wealth of information on how they can be applied to make the most out of their characteristics. Not only is there the possibility to learn about their material formations, but their reactions to heat can be uncovered by measuring them over time. A lot of plastics will begin to change, or melt, at temperatures just under 200°C. So implementing thermogravimetric testing with plastics can show at what point the material will start a phase transition.

Thermogravimetric testing displays an opportunity for uncovering a material’s properties with precision. If you want to learn more about thermogravimetric analysis, we, XRF Scientific, offer additional detail in our article: A Beginners Guide to Thermogravimetric Analysis. Here we examine the basics of thermogravimetric analysis, including how the tools work and where TGA can be applied. We also consider thermogravimetric analysis in relation to ISO 11358.

Make your next breakthrough with your materials through the capabilities of thermogravimetric testing. Contact us today to learn how our equipment could benefit your research.