Insights in block length distributions of thermoplastic polyurethanes and polyesters
The average length of the constituting blocks in a block copolymer can be determined by spectroscopy, notably NMR. However, no information is obtained on the block length distribution. This would be important information since especially the longer blocks fraction is thought to be responsible for e.g., crystallinity.
Recently, we investigated whether further insights in differences in block length distributions can be obtained by (off-line) coupled chromatography followed by NMR. By decoupling molar mass and chemical composition effects in the interactive chromatography step, access to block length distributional information can be obtained as was shown by NMR experiments of 2D fractions. From the accurate description of residual molar mass effects and via non-parametric deconvolution semi-quantitative differences in block length distributions between individual samples could be determined.
About the speaker
Harry Philipsen is Senior Expert Analytics at DSM Engineering Materials. He obtained a PhD in Analytical Chemistry with a scientific focus on molecular characterization of complex polymers. His current research interest is circularity of plastic materials and how analytical chemistry can facilitate the necessary transition. Former jobs were in line management and business development. He is Chairperson of the KNCV Discussion group Separation methods of Polymers (DSP) and former Chairperson of the KNCV Section Analytical Chemistry.