Papers with Barrier Properties

OPP producers have expanded the core, creating a foam stmcture with lower density, greater opacity, and a stiffer, more paper-Hke feel. Vacuum metallisation increases opacity and water-vapor barrier properties. 

Oil Repellent. Fluorochemicals are the only class of material that can provide oil repeUency without altering the porosity of the paper or paperboard. Physical barriers to oil penetration are used primarily for their moisture- or gas-barrier properties, with retarded oil penetration as a secondary benefit. The most common od-repeUent additives are long-chain perfluoroalkyl phosphate salts of ammonia or diethanol amine. Commercial sources include Scotchban (3M), Zonyl (DuPont), and Lodyne (Ciba Specialties). There are also a fluorochemical carboxylate salt, Lodyne (Ciba Specialties), and fluorochemical copolymers, eg, Scotchban (3M). The widest range of oily fluid holdout is provided by the fluorochemical copolymers. 

Layered Structures. Whenever a barrier polymer lacks the necessary mechanical properties for an appHcation or the barrier would be adequate with only a small amount of the more expensive barrier polymer, a multilayer stmcture via coextmsion or lamination is appropriate. Whenever the barrier polymer is difficult to melt process or a particular traditional substrate such as paper or cellophane [9005-81-6] is necessary, a coating either from latex or a solvent is appropriate. A layered stmcture uses the barrier polymer most efficiently since permeation must occur through the barrier polymer and not around the barrier polymer. No short cuts are allowed for a permeant. The barrier properties of these stmctures are described by the permeance which is described in equation 16 where and L are the permeabiUties and thicknesses of the layers. 

This paper describes the physical, chemical, and barrier properties of a new family of high molecular weight copolymers of acrylonitrile and styrene with acrylonitrile functionality in the range of 60-85 weight per-... 

H. Wu, L. T. Drzal, Graphene nanoplatelet paper as a light-weight composite with excellent electrical and thermal conductivity and good gas barrier properties., Carbon, vol. 50,... 

A common factor of metal foodstuff packaging is that it provides long term ambient stable storage with excellent abuse resistance and protection from environmental contamination ensuring food safety and quality retention with extended shelf life. Flexible packaging which is covered elsewhere in this book may also use thin layers of metal either as discrete foil layers or as metallised plastic or paper layers for improved barrier properties, but the main structural components are non-metallic and so are not covered here. 

Grease, Gas, and Water Barrier Properties of PVA-Coated Paper Before and After Grafting with a... 

To date, PHAs have been applied extensively for food packaging applications. Poly(3HB-3HV] shows suitable gas barrier properties to enable its application in beverage bottles. In addition PHA lattices can be used to coat paper and cardboard used in paper milk cartons [82]. Currently, drink cartons are often coated with polyethylene and/or aluminium foils to improve the barrier properties. As the resulting composite material is hard to recycle, PHA-coated cartons offer an interesting alternative. 

Rosin and its derivatives are frequently used as polymer additives in different capacities. Their role as plasticizers is illustratedby recent work related to the paper coating for foodpackaging with a 3-hydroxybutirate/3-hydroxy valerate copolymer (PHBW) [112, 113]. The addition of tall oil rosin to the copolymer was found to improve its water vapour barrier properties as well as to reduce the pinhole density of the corresponding laminated papers. 

Isotropic PHB foils possess excellent barrier properties against gas permeation. This is the rationale for potential applications in packaging, especially for food. The substitution of polyethylene terephthalate (PET) for bottle production seems to be especially attractive, considering the volume of PET waste. Another option consists in the modification of paper since paper/poly(HB-c<7-HV) foils are completely biodegradable, unlike paper coated with conventional foils [212]. The simplest apphcation is in containers, plastic bags and foils, commonly produced... 

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