How Do You Analyse Polymers?

From naturally occurring materials such as wool, silk and keratin to synthetic plastics derived from petroleum products, polymers come in an array of forms. Polymer characterisation allows scientists to map the unique properties of polymer materials and gain insight into parameters such as tensile strength, thermal expansion, elasticity, crystallinity and permeability. These parameters can be used to predict behaviours, assess performance and determine suitability for applications.

Read on to find out more about analytical methods for polymer characterisation.

Chromatographic methods for polymer analysis

Chromatography, a lab technique used to split mixtures and isolate individual compounds, is one of the most widely used polymer analysis techniques. Intertek is a global leader in chromatography analysis and manufacturers state-of-the-art instruments used for polymer characterisation. These include detectors for Gas Chromatography - Flame Ionisation (GC-FID), Gas Chromatography Mass Spectrometry (GC-MS) and Reversed Phase High Performance Liquid Chromatography (RP HPLC).

A new era of Molecular Weight Chromatography

More recently, the company has developed an advanced instrument for Molecular Weight Chromatography. The technique is called High Temperature Gel Permeation Chromatography (HTGPC) and is particularly useful for analysing polyolefin materials such as polypropylene and polyethylene. Insight into molecular weight reveals important data about structural and mechanical characteristics. Information can be used to assess performance and assign industrial ratings.

Thermal methods for polymer analysis

Temperature can have a drastic impact on how polymers behave and perform. This makes thermal polymer analysis techniques an important stage of product research and development. Many labs use thermal methods such as Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA) to measure the physical properties of polymer materials. This includes high-performance thermoplastics, composites and resins used for industrial applications.

Thermal analysis allows scientists to develop a deep understanding of polymer properties. Insight can be used to fast track product development, address weaknesses, maintain quality control and support decision making processes. For example, DSC may be used to assess how well a marine-grade plastic resists thermal decomposition. Or how fast a polyvinylchloride (PVC) product used to insulate electrical wires undergoes oxidative degradation when exposed to high temperatures.

“Across many industries, it is essential that the properties of polymers, raw materials and finished products are well understood as they are integral to enhancing the performance of materials to meet specifications for the desired end-use, and within the remit of product failure analysis,” reads a statement from Intertek.

Spectroscopic methods for polymer analysis

Spectroscopy, the study of how matter absorbs and emits light, has emerged as a useful tool for polymer analysis. Spectroscopic techniques are used to analyse the structure of polymer materials and observe physical and chemical changes when exposed to different environmental conditions.

From petrochemical product development to environmental research, polymer characterisation techniques are used across a wide range of sectors and industries. Find out more about the different methods used in ‘Polymer Characterisation - Techniques, Types & Properties’.