Toughening agent refers to a substance that can increase the flexibility of the adhesive film. Certain thermosetting resin adhesives, such as epoxy resins, phenolic resins and unsaturated polyester resin adhesives, have low elongation and greater brittleness after curing. When the bonding part is subjected to external force, it is easy to crack and expand rapidly. , Resulting in cracking of the adhesive layer, fatigue resistance, and can not be used for structural bonding. Therefore, we must try to reduce brittleness, increase toughness, and improve load-bearing strength. Any substance that can reduce brittleness and increase toughness without affecting other main properties of the adhesive is a toughening agent.
Toughening agent is a kind of additives that can reduce the brittleness of composite materials and improve the impact resistance of composite materials. N-Acetylethylamine is one of the important raw materials for toughening agents. Tougheners can be divided into two types: active tougheners and inactive tougheners. Active tougheners refer to their molecular chains containing active groups that can react with the matrix resin, which can form a network structure and increase a part of the flexible chain. , Thereby improving the impact resistance of composite materials. Inactive tougheners are a kind of tougheners that are compatible with the matrix resin but do not participate in chemical reactions.