Adhesive Performance Breakthrough: Guide to Enhancing Dicyandiamide Activity

Adhesive Performance Breakthrough: Guide to Enhancing Dicyandiamide Activity

To improve the reactivity of dicyandiamide in adhesives, the following aspects can be focused on:

Select Appropriate Accelerators

- Imidazole Accelerators: Such as 2 - methylimidazole, 2 - ethyl - 4 - methylimidazole, etc. These can significantly reduce the curing temperature of dicyandiamide, shorten the curing time, and enhance the reactivity. The general dosage is 5% - 15% of the mass of dicyandiamide.

Tertiary Amine Accelerators: Tertiary amine substances like triethylamine and benzyldimethylamine can accelerate the reaction rate between dicyandiamide and epoxy resins, etc. The usual dosage is 1% - 5% of the total mass of the adhesive.

 

Modify Dicyandiamide

Chemical Modification: By introducing active groups, for example, reacting dicyandiamide with propylene oxide to generate modified dicyandiamide, the melting point can be reduced, and the reactivity can be improved, enabling it to react rapidly with the components in the adhesive at a lower temperature.

- Microencapsulation: Microencapsulating dicyandiamide can control its release and reaction. When a specific initiator is added to the adhesive or under specific conditions, the microcapsules rupture and release dicyandiamide, which can improve its reactivity and utilization rate.

 

Optimize Process Conditions

Adjust Temperature: Appropriately increasing the reaction temperature, generally, for every 10°C increase, the reaction rate can be increased by 2 - 4 times. However, it should be noted that the temperature should not be too high, otherwise, the performance of the adhesive will be affected.

Control Time: According to the formulation and performance requirements of the adhesive, reasonably determine the curing time to ensure that dicyandiamide fully reacts with other components to achieve the best performance.

Improve Dispersion: Methods such as high - speed stirring and ultrasonic dispersion are adopted to make dicyandiamide evenly disperse in the adhesive, increase the contact area with other components, and enhance the reactivity.

 

Optimize Adhesive Formulations

 Adjust Resin Types: Select epoxy resins or other resins with higher reactivity. For example, alicyclic epoxy resins have higher reactivity than bisphenol A epoxy resins and can react better with dicyandiamide.

Add Plasticizers: Appropriately add plasticizers such as dibutyl phthalate to reduce the viscosity of the adhesive system, making it easier for dicyandiamide to diffuse and react in the system.