Development of Polyurethane Modified Epoxy Resin Adhesive III

As can be seen from Figure 9, the brittleness of the modified epoxy resin was improved, and the shear strength was significantly increased when the amount of addition was small. The highest shear strength was obtained when the amount of addition was 10 parts, and then began to decline, especially at 80°C. The 150°C shear strength is already very low when the amount added exceeds 50 parts.

As can be seen from Figure 10, the modified epoxy resin peel strength and impact strength have been significantly improved. The impact strength was the highest when the amount was 20 parts, and then began to decline; after 30 parts, the impact strength began to increase again, reached the maximum at 70 parts, and then began to decline again. The peel strength was highest at 30 parts added, then dropped sharply, reached a minimum at 50 parts, and then gradually increased.

This is also due to the fact that as the amount of addition increases, the modified epoxy resin results from the phase separation of the epoxy resin continuous phase and the polyurethane dispersed phase to the bicontinuous phase.

2.3.2 Room temperature curing temperature curing agent A curing system

The modified epoxy resin was cured at room temperature for 7 days using A as a curing agent, and the adhesion performance was tested. The results are as follows:

As can be seen from Table 1, the modified epoxy resin at room temperature shear strength has been greatly improved, the highest when the amount of 30 people added; peel strength has also been greatly improved; but the shear strength at 90 °C with The increase in the amount of addition has been declining.


(to be continued)