35. Durability of Nonstructural Adhesives

In all bonded assemblies, the durability of the adhesive or sealant joint is important to the integrity of the article concerned. The considerations of joint design, adhesive, sealant and substrate selection, surface preparation, and primer selection along with methods of application including mixing procedures, application techniques, and joint assembly are all reviewed. Methods of evaluation of durability and test regimes including exposure to elevated and reduced temperatures, UV radiation, moisture, saline solutions, stress, and fatigue, both individually and combined in cycles, are considered. The relevance and application of these test condition to specific situations are discussed, including the role of antioxidants and cross-linking additives to improve durability. Reference is made to the corresponding standards according to the major standard organizations, such as the International Standards Organization (ISO), the European Committee for Standardization (CEN), and the British Standards Institute (BSI), and also to European directives and regulations and national legislation.