增韧剂的概述作用原理总结

Summary of the principle of toughening agent

增韧剂，是指能增加胶黏剂膜层柔韧性的物质。某些热固性树脂胶黏剂，如环氧树脂、酚醛树脂和不饱和聚酯树脂胶黏剂固化后伸长率低，脆性较大，当粘接部位承受外力时很容易产生裂纹，并迅速扩展，导致胶层开裂，不耐疲劳，不能作为结构粘接之用。因此，必须设法降低脆性，增大韧性，提高承载强度。凡能减低脆性，增加韧性，而又不影响胶黏剂其他主要性能的物质即为增韧剂。可分为橡胶类增韧剂和热塑性弹性体类增韧剂。

Toughening agent is the material that can increase the flexibility of adhesive film. Some thermosetting resin adhesives, such as epoxy resin, phenolic resin and unsaturated polyester resin adhesive, have low elongation and high brittleness. When the adhesive part bears the external force, it is easy to produce cracks and expand rapidly, resulting in the cracking of the film, fatigue and cannot be used as a structural adhesive. Therefore, we must try to reduce brittleness, increase toughness and increase bearing strength. Any substance that can reduce brittleness and increase toughness without affecting other main properties of adhesives is a toughening agent. It can be divided into rubber toughening agent and thermoplastic elastomer toughening agent.

增韧剂一般都含有活性基团，能与树脂发生化学反应，固化后不完全相容，有时还要分相，会获得较理想的增韧效果，使热变形温度不变或下降甚微，而抗冲击性能又明显改善。一些低分子液体或称之为增塑剂之物加入树脂之中，虽然也能降低脆性，但刚性、强度、热变形温度却大幅度下降，不能满足结构粘接要求，因此，增塑剂与增韧剂是完全不同的。

The toughening agent generally contains active groups, which can react with the resin. After curing, the toughening agent can not be completely compatible, and sometimes it is also phase separation. The toughening agent will get a better toughening effect, make the thermal deformation temperature change or decrease slightly, and the impact resistance performance is obviously improved. Some low-molecular-weight liquids or plasticizers are added to the resin, although they can also reduce brittleness, but the rigidity, strength and thermal deformation temperature drop greatly, which can not meet the requirements of structural adhesion. Therefore, plasticizers and toughening agents are completely different.