PMSE 81 |
| A variety of thin, functional coatings can be produced using layer-by-layer (LbL) assembly. Thin films, typically < 1µm thick, are created by alternately exposing a substrate to positively- and negatively-charged molecules or particles in water. This deposition process is repeated until the desired number of “bilayers” (or cationic-anionic pairs) is achieved. Two functionalities, electrically conductive films made with carbon black and oxygen barrier films made with clay, are described here. Coatings made from poly(acrylic acid) and polyethylenimine stabilized carbon black are able to achieve a sheet resistance of 500 ohm/square with a thickness of 5.4 µm. These conductive films can be patterned using traditional photolithography. Coatings of sodium montmorrilonite clay and cationic polyacrylamide, that are less than 500 nm thick, have been produced with an oxygen transmission rate below 0.005 cm3/m2-day. These thin, transparent composites are a good candidate for foil replacement in food packaging and flexible electronics packaging. |
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Tess Award Symposium in Honor of L. E. (Skip) Scriven
8:00 AM-12:05 PM, Monday, August 20, 2007 Westin Boston Waterfront -- Grand Ballroom D, Oral
Division of Polymeric Materials: Science & Engineering |