Nylons (polyamides) are thermoplastic materials that are widely used in the automotive and other engineering industries because they offer beneficial properties like high impact strength, stiffness and ductility. Semi-crystalline variants such as nylon (PA) 6,6 also have good resistance to heat and organic chemicals. However, whilst this chemical resistance provides in service benefits, constructing components from PA 6,6 can be difficult if adhesive bonding is required as part of the manufacturing process. This means that surface preparation is usually necessary to ensure effective bonding.
Oxford Advanced Surfaces has demonstrated how Onto adhesion promotion technology can be used to prepare PA surfaces for bonding. 5mm thick PA 6,6 plaques were bonded together with an A-stage epoxy adhesive for lap shear testing. When no surface preparation was carried out, adhesive bond failure occurred at 2.2MPa. The company say that when Onto was used to treat the surface of the PA the bond was improved to such an extent (6.1MPa) that the substrate snapped before the bond could fail.
Double lap shear tests were run on the same PA substrate using a B-stage epoxy and again Onto treatment resulted in substrate snapping whereas no surface preparation led to adhesive bond failure.
Onto SB1000 is a range of products designed to promote the adhesion of polyurethane and epoxy adhesives to plastics, composites and other advanced materials like aluminium. Onto adhesion promoters create opportunities to use the optimum combination of materials by removing the constraints of poor bonding. Not only does this enable superior product design, but it is a practical approach to surface preparation that simplifies the manufacture of products from advanced materials.