Layer-by-Layer Electrostatic Self-Assembly at the Industrial Scale

Layer-by-Layer Electrostatic Self-Assembly at the Industrial Scale

Lee Boman
Eastman Chemical Company

"Twenty-five years after the first laboratory research describing the Layer-by-Layer technique of producing nanoscale thin-film coatings appeared, the field has generated hundreds of graduate theses, more than ten thousand journal publications, and even a few companies. For years, however, this technology has been confined to the bench-top, functionalizing surfaces with a wide range of properties from electrical performance to gas separation, catalysis to drug delivery, light management to water management, to name a few, but rarely more than a few square inches in size. Only in recent years has the true potential of Layer-by-Layer (LbL) been unlocked as the technology was adapted to a roll-to-roll platform. While the principles of web handling and spray-coating are well understood by the coating world, the traditionally time intensive practice of dip-coating solutions of the macromolecules, which are the workhorse building blocks of Layer-by-Layer research, required significant engineering integration. This talk will present a brief background of the technical basis for electrostatic self-assembly, and where the bench-top variety of this coating process was constrained when it came to scaling to industrial viability. The magnitude of LbL coating equipment in operation today will also be described. This metamorphosis from lab-scale R&D tool to continuous production equipment gives us some insight as to where LbL best fits into the spectrum of coating technologies along with its strengths and weaknesses. Evidence will be presented that LbL technology has reached a level of maturity where bench-scale applications, industrial-scale equipment, and a deep process understanding have created a platform that is ready to make the crucial jump to commercial production. The recent acknowledgment of this progress by major players within the materials industry suggests that sustainable products not simply incorporating LbL functionality but featuring it prominently, are a near-term inevitability. "