Fuente: Journal of applied polymer Lugar: RESEARCH ARTICLE Schematic representation of the development and application of a clean-peel composite adhesive for medical paper-plastic packaging. The composite liquid adhesive (CLA) was prepared through sequential mixing of diluted EAA, PEG-6000, GI, soap, and CAA. After coating on medical dialysis paper (MDP) and laminating with polyethylene (PE) film by heat-sealing, the composite exhibits a peel strength of 2.218 N. The peel process involves cohesive failure within CLA and adhesive failure at the CLA-MDP interface, achieving clean separation without MDP damage or fiber residue, which facilitates the recycling of waste paper-plastic composites.


ABSTRACT
Paper-plastic composite materials are extensively utilized in the food, chemical, and pharmaceutical industries due to their superior physical properties and environmental performance. However, paper substrates lack inherent heat-sealability and cannot be directly laminated to plastic films. Researchers have enhanced the heat-sealing properties of paper via approaches such as chemical modification and surface coating with adhesives. Nevertheless, despite substantial advancements in endowing paper with heat-sealability, limited research has focused on the clean peelability of paper-plastic composites. In the present study, a water-based ethylene-acrylic acid (EAA) heat-seal adhesive was employed as the primary binder. A composite adhesive was formulated through the incorporation of additives, including polyethylene glycol 6000 (PEG-6000), WE-110B2 emulsifying wax, glycerol (GI), soap, and a composite soy-based defoaming agent (CAA). Utilizing medical dialysis paper (MDP) and polyethylene (PE) film as substrates, the effects of additive type and concentration on the peel strength of the composites were investigated. By optimizing the additive ratios, an adhesive was successfully developed that ensures adequate heat-sealing strength while enabling clean peeling. This work presents a viable solution to the challenges associated with the sorting, recycling, and reuse of waste paper-PE film composites.