Saran PVDC Barrier Concepts for Demanding Coextrusion and Lamination Applications, 2005 European PLACE Conference

Copolymers of polyvinylidene chloride (PVDC), are-well known for their use in demanding barrier packaging applications to minimize the permeation of oxygen, water vapor, and odors. New die designs incorporating Dow’s patented early encapsulation technology (US Patent 6,685,872, International Publication Number WO 02/06047, US Patent 4,643,927), coupled with temperature isolation technology from Brampton Engineering and Macro Engineering, have eliminated degradation problems existing in the typical spiral mandrel dies used in the blown film process. These new die designs, coupled with new Saran* resin offerings; enable PVDC resins to be processed on large multilayer blown film dies. Multilayer films incorporating PVDC resins with higher temperature polymers such as Nylon, PP, and LLDPE in the skins are now possible.

The advantage of coextruded multilayer films incorporating PVDC in the offering, in a one step process, is the combination of outstanding barrier performances, resistance to in-use conditions such as humidity and flexes cracking, and specific physical properties given by the skin polymers. It represents the possibility to increase product shelf life or down gauge the barrier material as well as reducing processing steps compared to laminated composite products.