ZL-DHP lignin model compound at the air–water interface Original Research Article

In this paper we present our surface chemistry studies of enzymatically polymerized, poly-coniferyl alcohol lignin model compound (dehydrogenate polymer a.k.a. ZL-DHP) at the air–water interface. Using the CHCl3/MeOH (5:1 v/v) spreading solvent, we found an average molecular area of ZL-DHP of approximately 1200 Å2. The monolayer expresses a high compressibility with a collapsed area of 500 Å2 and collapsed surface pressure of 28 mN m−1. In the range of applied surface pressures, ZL-DHP polymer have no phase changes, as shown by the very high linearity (R=0.994) of absorbance vs. surface pressure cure. There was no symmetry transitions observed as shown by absence of shifts of absorption peak maximums.