Tuning Interfacial Adhesion in Polyester/Polyamide Systems

Polymer–polymer adhesion is critical in polymer processing and application areas where lamination, welding, composites, blending, and coextrusion are involved. Polyethylene terephthalate/polyamide (PET/PA) pairs are widely used to produce bicomponent fibers. The strong adhesion due to the formation of chemical bonds in the interfacial region limits post-production fiber processing. The adhesion strength in the PET/PA systems showed that PET/PA66 had the highest adhesion energy, followed by PET/PA6, PET/PA11, and PET/PA12 for all processing conditions. We developed a method that enables adhesion control by introducing a poly(octadecene-alt-maleic anhydride) (POMA) alternating copolymer by either direct interfacial modification or addition into the PET phase. Upon POMA introduction to the system, the reduction in interfacial adhesion strength between PET and polyamides is observed. We established the relationship between adhesion strengths in PET/polyamide systems, processing conditions, and concentration of the POMA modifier.