To understand any practical laboratory testing procedure, it is crucial to get familiar with the basics of a process. Polymers are widely used in several applications. Furthermore, there are many products made out of polymers which have extensive utility. TGA analysis is a type of testing which is carried out on various materials. The fundamentals of this procedure are indeed simple to grasp.
WHAT IS TGA ANALYSIS?
The abbreviation- TGA stands for ‘Thermogravimetric analysis’ and is done in thermal analysis lab. This type of testing falls under the thermal analysis domain. The testing is crucial to determine material behaviour under different temperature ranges.
In simple words, TGA analysis measures the mass of a specific sample as it is heated. This sample is heated over a particular period. The weight of the sample changes after application of heat. This change in weight is simultaneously recorded by the TGA instruments Software.
TYPES OF TGA ANALYSIS
As mentioned earlier, the TGA analysis is a thermal procedure. Therefore, the testing varies according to the application of heat. The following are the main types of Thermogravimetry:
Isothermal Thermogravimetry :
In this test, the heat applied to a sample is kept constant. Hence, the readings are taken with respect to time.
This technique is comparatively complicated than Isothermal TGA. The sample like polymer or other material is heated in a predetermined sequence. This sequence is separated by isothermal intervals. Unlike other methods, the sample mass attains stability. Subsequently, the succeeding temperature is applied.
The heat application is done in a linear aspect.
TGA ANALYSIS OF POLYMERS- THE PROCEDURE
Various factors determine product functionality. Hence, proper testing of products is vital. The TGA analysis of polymers is carried out on a Thermogravimetricanalyser in TGA/Thermal Analysis Testing Lab. Before understanding the basic construction of a Thermogravimetric analyzer, it is important to get a glimpse of polymer testing at our laboratory:
- We ensure and adhere to the international standards while performing any tests.
- The TGA analyzer delivers accurate results.
- Adequate safety norms are followed in our laboratory while performing the TGA analysis of polymers.
- The readings are accompanied by TGA curves and graphs as per customer requirement.
The Thermogravimetricanalyser in TGA Analysis Testing Lab is vital equipment which measures the weight of a sample. The construction of TGA analyzer is simple to understand.
- A TGA analyzer is vertical-built testing equipment.
- A typical TGA analyzer comprises of some basic accessories for operation.
- The main components of a typical TGA analyzer areweighing pan, enclosure, and furnace/oven.
- The weighing pan is used to calculate the weight of the sample at predetermined points.
- The enclosure is generally embedded in a furnace/oven of the analyzer.
- A temperature control knobs adjust the heat increment inside the oven.
- As heat is applied, the sample undergoes a transformation in weight.
- Generally, TGA analysis is performed on polymers and composite materials.
TGA ANALYSIS OF POLYMERS- NEED AND UTILITY
Different polymer products are used in a variable temperature environment. Hence, it is indeed vital to assess the material behaviour under the specified temperature range.
A TGA analysis serves this purpose. Furthermore, it generates the TGA curves. These curves/graphs provide accurate information about material behaviour. TGA analysis determines the thermal stability of a material.
TGA analysis of polymers is done to:
- Determine residual contents like fibre present in a composite.
- Gauge the material behaviour like expansion, contraction and melt flow.
- Evaluate the thermal stability of a polymer.
- Study the material behaviour against combustion parameters like oxidation.
- Record the weight loss of a specific sample at different junctions of temperature application.
TGA analysis of polymers is needed to:
- Establish the product stability data for proper quality control.
- Provide vital information about weight loss of various samples. This enables the Research and development team to try the desired polymer compositions before product finalization.
- Observe the residual components present in a polymer or composite material.
Utility of TGA testing:
As polymers are used abundantly in the modern world, it is indeed important to perform the necessary tests. Polymers are used in textiles, plastics, aircraft, electrical components and other miscellaneous areas. Hence, TGA analysis done in thermal analysis lab serves as a perfect technique to determine the utility of polymer material.
The data which is gathered from TGA testing can be plotted as a systematic curve. This is known as TGA curve or TGA graph. The resulting curve is often smooth. Alternatively, some materials may behave unexpectedly. This results in some variation of the typical TGA curve.
There are two basic types of Thermogravimetric graphs. As mentioned earlier, TGA is a thermal technique which generates the weight differential of a material. Hence, the weight is a function of temperature or time. Likewise, the two types of TGA curves are:
- Weight (%) vs. Temperature
The mass or its percentage of an initial reading before testing is plotted on the Y-axis. The temperature (Preferably in degree Celsius, although not limited) is plotted on the X-axis.
The mass or its percentage of an initial reading before testing is plotted on the Y-axis. The time (Preferably in seconds, minutes or hours) is plotted on the X-axis.
Criterion Scientific is committed to delivering the results to you that makes sense. We deliver results with meaningful correlation of the test data with your situation. A typical TGA thermogram is presented in below image. The TGA thermogram shows that the Polymer content is 99.55% and the Ash content or the Inorganic filler content is limited to only 0.45%. This TGA analysis thus shows that the sample is a single component polymer and is primarily unfilled.