Crystallinity of PET affects several mechanical properties such as stiffness, density, permeation, transparency and thermal stability. NIR spectroscopy can measure crystallinity and several other properties quickly, non-destructively and by non-laboratory personnel.
The main benefits of FT-NIR technology for PET packaging analysis lie in its unique combination of versatility, precision, and ease of use. Performing routine FT-NIR measurements on a set of PET containers is a simple operation that does not require any analytical background and allows the rapid determination of several key properties and quality attributes of each sample. As well as % crystallinity NIR can also measure intrinsic viscosity, moisture and wall thickness. FT-NIR analysis is an environmentally-friendly approach with no solvents required and enables a significant increase in the throughput of industrial analytical laboratories, both in terms of sample volume and also number of property determinations per sample.