title: Super Oxygen and Improved Water Vapor Barrier of Polypropylene Film with Polyelectrolyte Multilayer Nanocoatings.
abstract: Biaxially oriented polypropylene (BOPP) is widely used in packaging. Although its orientation increases mechanical strength and clarity, BOPP suffers from a high oxygen transmission rate (OTR). Multilayer thin films are deposited from water using layer-by-layer (LbL) assembly. Polyethylenimine (PEI) is combined with either poly(acrylic acid) (PAA) or vermiculite (VMT) clay to impart high oxygen barrier. A 30-bilayer PEI/VMT nanocoating (226 nm thick) improves the OTR of 17.8 μm thick BOPP by more than 30X, rivaling most inorganic coatings. PEI/PAA multilayers achieve comparable barrier with only 12 bilayers due to greater thickness, but these films exhibit increased oxygen permeability at high humidity. The PEI/VMT coatings actually exhibit improved oxygen barrier at high humidity (and also improve moisture barrier by more than 40%). This high barrier BOPP meets the criteria for sensitive food and some electronics packaging applications. Additionally, this water-based coating technology is cost effective and provides an opportunity to produce high barrier polypropylene film on an industrial scale.
authors.affiliation: Department of Mechanical Engineering and Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA.
authors.forename: Yixuan
authors.initials: Y
authors.lastname: Song
authors.affiliation: Department of Mechanical Engineering and Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA.
authors.forename: Ping
authors.initials: P
authors.lastname: Tzeng
authors.affiliation: Department of Mechanical Engineering and Department of Materials Science and Engineering, Texas A&M University, College Station, TX, 77843, USA.
authors.forename: Jaime C
authors.initials: JC
authors.lastname: Grunlan
mesh_terms: D004573:Electrolytes / Q000737:chemistry; D015394:Molecular Structure; D053761:Nanocomposites / Q000737:chemistry*; D010100:Oxygen / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D014835:Volatilization; D014867:Water / Q000737:chemistry*
chemical_list: D004573:Electrolytes; D011126:Polypropylenes; D014867:Water; D010100:Oxygen
keywords: clay nanoplatelets; layer-by-layer assembly; moisture vapor transmission rate; oriented polypropylenes; oxygen transmission rate