Nondestructive quantitative determination of starch content in polyethylene by solid state NMR and FTIR

Fourier transform infrared spectroscopy (FTIR) and carbon‐13 solid state nuclear magnetic resonance spectroscopy (NMR) were used quantitatively (and non‐destructively) to determine the starch content in a series of starch filled polyethylene samples (nominal addition levels range from 3 to 6 wt%). Data acquisition times (including sample preparation and instrument analysis) were typically a few minutes for both techniques. Current methodologies for starch analysis in polyethylene are based upon wet chemical techniques (gravimetric or enzyme analysis). The proposed methods offer several advantages over these traditional methods: they are less labor intensive, do not require chemical reagents, are relatively insensitive to changes in the sample matrix, and are fast.