Raman Analysis Case Study

Vibrational Spectroscopy, using optical radiation to probe the structure of materials by looking at how molecules vibrate, is one of the most versatile analytical tools available. On scales from microns to meters and picograms to tons, it's a vital way to identify chemical structure and physical form in products ranging from pharmaceuticals to advanced materials.

Dr. Neil Everall heads Intertek's Vibrational Spectroscopy unit, and is a recognised expert in infrared and Raman spectroscopy, with over 70 research publications in the field. He says: "We are continually trying to develop and use these techniques to better understand and improve the structure and properties of materials."

"We use infrared and Raman spectroscopy to understand competitive materials and to test our customer's own materials - are they performing in the way they need to, and if not, why not?" For example, Neil's team developed a novel approach to rapidly characterise the polymer structure in plastic soft-drink bottles, so that they could be produced in a form that didn't crack, warp or go hazy.

"We were able to quickly map complex orientation and crystallinity fields over bottle surfaces, and relate these to in-use properties," he added.

The ability to characterise a bottle and optimise production based on this feedback was crucial, and was a key technical advantage for the resin producer when selling to the bottle manufacturer. The supporting science can sometimes be almost as important as the product itself in securing a sale. Neil and his team get involved with customers right the way through from their original research to their finished products, including ongoing technical support,of established products, and the development of quality-control techniques that can be used at the production facility, troubleshooting problems before they occur.

"We can study and optimise reactions as they occur, either in a reaction flask in the laboratory, or inside a full-scale production reactor. And because our equipment is portable, we can make these measurements anywhere, anytime."

A recent example of front-end R&D was the development of a new Raman micro-spectroscopy technique that could image polymer phase distributions in a carbon-fibre composite used for aerospace applications. "With this tool we helped our customer optimise their production process to give the desired phase structure: something that no one else could even measure, let alone control."

"We have also used this so-called spectroscopic imaging approach to help pharmaceutical companies to investigate the structure of tabletted formulations, where its very important to visualise the distribution of actives, excipients and coatings. Similarly, we have worked with paints and packaging companies to image cure profiles in coatings, thereby improving scratch resistance and adhesion properties. The ability to visualize properties as images is and incredibly useful tool," says Everall. Spectroscopic imaging is widely exploited within Intertek as a front-line research and analytical tool for many product sectors.