Mechanism of Adhesive in Secondary Bonding of Fiberglass Composites with Peel Ply Surface Preparation

摘要

The surface composition and morphology of fiberglass/epoxy composites prepared by the use of "bondable" peel ply and sanding will be presented. "Bondable" peel ply is a material which provides a surface ready for secondary bonding following peel ply removal without requiring further treatment. The available results indicate mechanisms which may degrade bonds using "bondable" peel ply. Those same results also give insight into how "bondable" peel ply achieves a bondable surface when conditions are optimal. Optimal conditions can produce a surface whose 90° peel strength is 12-15 lbs/in-width versus sub-optimal conditions which produce strengths of 1-4 lbs/in-width. The case studied in this effort is 350℉ curing fiberglass/epoxy bonded secondarily with 250℉ curing toughened epoxy adhesive.