Modeling Hygral Stress Profiles and Edge Waving in High-Bulk Recycled Cartonboard Skids
Modeling transient moisture gradients and hygral stress in high-bulk recycled cartonboard skids establishes barrier wrap limits to prevent press edge waving
Stretch Wrap Barrier Film
Polymer Structure
Elastic polymer encapsulation protects paper reels and stacked paperboard pallets from atmospheric moisture ingress during transport and storage. Packaging technology defines stretch wrap barrier film as a co-extruded plastic film possessing high elongation, puncture resistance, and low water vapor transmission rates wrapped under tension around paper products. Co-extruded barrier layers prevent ambient humidity from disrupting paperboard equilibrium moisture content.
Barrier Action
Flexible film formulations combine linear low-density polyethylene for stretchability and cling with specialized polar polymers like ethylene vinyl alcohol or polyvinylidene chloride to retard vapor migration. Automated wrapping systems apply pre-stretched film under elastic tension, creating tightly bound containment around paper rolls or palletized folding cartons. Elastic recovery forces maintain continuous contact with package contours, sealing overlapping film layers into a moisture barrier.
Unprotected paperboard absorbs moisture in transit, causing edge swell, wavy edges, and loss of stack compression strength in humid storage environments. Barrier films prevent moisture loss in dry climates, preventing brittleness and cracking along carton crease lines. Puncture resistance prevents film tearing from sharp pallet corners or handling equipment contact.
Protection Boundary
Standard laboratory methods measure water vapor transmission rates in grams per square meter per twenty-four hours to verify film barrier efficiency. Film degradation from mechanical punctures or inadequate overlap thickness permits localized moisture penetration, damaging paper edges. Stretch wrap barrier film provides essential environmental protection for moisture-sensitive paperboard shipments across global logistics networks.