Atomic force microscopy (AFM) investigation of Langmuir-Blodgett (LB) films of sugar cane bagasse lignin

The morphological features of Langmuir-Blodgett (LB) films of pure lignin extracted from sugar cane bagasse and composites of lignin and cadmium stearate have been investigated using atomic force microscopy (AFM). Results indicated that despite the non-amphiphilic nature of lignin and associated relatively poor stability and transferability of the lignin monolayer, the surface of the film is smooth at the micron level and comparable to that of LB films from typical amphiphilic compounds. Distinct domain structures from lignin and cadmium stearate could be visualized in the composite LB film even in one monolayer thick LB films. The mean surface roughness increases with increasing numbers of layers.