LANGMUIR-BLODGETT MULTILAYER ASSEMBLY BY A CONTINUOUS PROCESS USING A STEADILY FLOWING SUBPHASE

A continuously operating Langmuir-Blodgett (LB) trough was developed and set up using two basins of different fluid levels connected by a ramp. Water as subphase was circulated by a tube pump to generate a steady laminar flow film on the ramp and thereby compressing the molecules on the surface to form a monolayer. Spreading, compressing, and transferring occurred simultaneously at three spatially separated regions. The surface pressure in the monolayer was measured as a function of the flow conditions. Parameters were the volumetric flow rate of the subphase, the difference of fluid level in the two basins, and the slope of the connecting ramp. The flow conditions were modeled with the purpose of predicting the surface pressure in the monolayer. The theoretical predictions agree reasonably well with the experimental results. LB films of more than 100 layers of LB forming rigid-rod polymers were transferred onto solid substrates using this continuous processing mode.