Polyvinyl chloride (PVC) is one of the most common polymers manufactured. It is very important that the plasticiser content of PVC is within specification limits, ensuring that the product has the correct hardness and flexibility for its end use. Pre-plasticised PVC is rigid and brittle but the addition of plasticiser along with other additives can produce materials with a range of physical properties from the very rigid to extremely flexible. Since the content of plasticiser in PVC is the primary determinant of flexibility, it is essential to monitor plasticiser levels in order to obtain reproducible mechanical behaviour.
The traditional method of testing is to dissolve the plasticiser in organic solvent and then to determine the amount of dissolved oil in the solvent either by gravimetric analysis (following distillation), infrared spectroscopy or gas chromatography. These methods can be time consuming, require skilled operators and the use of hazardous solvents.
Our benchtop NMR analyser, MQC+, provides an alternative method which is quick and easy to perform, simple to calibrate, and requires minimal sample preparation. As such it has become ideal for routine operations control either in laboratory or production environments within manufacturing plants of many of the world's leading polymer companies - without any requirement for additional chemicals and specialist operator training.