Plastics have become a major part of many businesses today. In fact, many modern product components contain plastic parts to provide less weight, resist corrosion and as a cost effective measure. However, it’s very important to make sure your plastic parts are performing properly and if problems arise, you need a way to uncover and correct them. TGA analysis is an important tool for examining specific properties of materials. Here is more about the process and the many benefits it can provide.
Thermogravimetric Analysis
TGA stands for thermogravimetric analysis. To better understand the concept, think of a specimen or test material which is heated. As heat is applied it I will get either heavier or lighter. To receive accurate results, tests are performed with a specific amount of heat within a controlled environment. TGA analysis is all about measuring material weight as it reacts to heating or cooling.
TGA thermal testing is done in one of two ways, either bottom loading or top loading. With top loading, the sample is placed in a pan which resides above the balance weighing mechanism. With bottom loading, the pan is suspended from the balance mechanism. Both processes use highly accurate methods to measure the effects of gravity (weight).
How Can Heat Affect Weight?
With materials like resins and plastics, heat can cause evaporation or burning away of specific ingredients. For example, heating causing drying out and this removes water. Heat can also remove solvents, fillers, plasticizers and other ingredients. This will result in a loss of weight and can also change physical properties.
A Simple Explanation
In order to provide an easy to understand explanation of one form of TGA testing, let’s examine a fiberglass insulation sample. In order to maintain proper thermal performance, a special binder is used which contains resins and other ingredients. In order to find out how much binder is in the material a sample is weighed and then placed in a testing oven with very high temperatures. This will eventually burn away all the binder, leaving only the glass fibers. The sample is then weighed again and with simple mathematics, the QC technician knows the exact binder percentage.
Tracking Data
Oxidation can also occur with heating and TGA analysis can determine oxidation, combustion and thermal stability. These are important considerations for many modern day materials. Exact measurements can be received and recorded onto a graph. The x axis can refer to temperature while the y axis denotes mass or weight loss. This provides engineers and manufacturers detailed data on how a material performs as heat is applied or removed.
This is a simple explanation of how TGA analysis works. In order to better understand the process, talk to polymer lab professionals. They can help you with all your testing needs and provide valuable advice and information.