Selection Based on the Chemical Properties of the Substrate
Some substrates contain polar groups; therefore, it is essential to select an adhesive capable of undergoing a chemical reaction with them, as this serves to enhance the strength of the bonded joint.
Selection Based on the Physical Properties of the Substrate
This encompasses the substrate's surface tension, its solubility in the adhesive's solvent, and its specific surface characteristics-such as rigidity, elasticity, and toughness.
Selection Based on the Specific Requirements of the Bonded Joint
Given the vast diversity of bonding materials and the ever-changing environments and conditions in which they are utilized, it is imperative to select an appropriate adhesive based on the specific requirements of the bonded joint. These requirements include mechanical strengths-such as tensile, flexural, peel, and impact resistance-as well as performance characteristics like resistance to high temperatures, water, oil, and low temperatures, in addition to specialized functions (e.g., optical or electromagnetic properties).
Selection Based on Curing Requirements
The curing process of an adhesive is influenced by various conditions, including temperature, pressure, time, and the presence of air. Some adhesives require heat to cure, others require applied pressure, while some necessitate isolation from air; consequently, one must select an adhesive with curing requirements that align with the specific conditions of the intended application environment.
