Performance Characteristics of Epoxy Resin Materials and Their Cured Products

Features of epoxy resin curing agents

There are many types of epoxy resin curing agents, and with the addition of numerous accelerators, modifiers, additives, etc., they can be combined and formulated into various high-performance, distinct epoxy curing systems and products. This makes them capable of meeting the requirements for various usage and process performance, which other thermosetting resins cannot compare to.

Understanding the properties of epoxy resin materials and their curing products

High Mechanical Properties

Epoxy resin materials have strong cohesive force and molecular structure, making their mechanical properties higher than general thermosetting resins like phenolic resins and unsaturated polyesters.

Excellent Adhesion Properties

The active epoxy group, hydroxyl group, polar groups such as ether, amine, ester, and other functional groups in the epoxy resin curing system can provide high adhesion strength to the cured epoxy products, and combined with its high cohesive strength and other mechanical properties, epoxy resin can be used as a structural adhesive.

Low Curing Shrinkage

Generally, it is 1% to 2%, which is the smallest among thermosetting resins (phenolic resins are 8% to 10%, unsaturated polyesters are 4% to 6%, and organic silicone resins are 4% to 8%). It also has a small coefficient of linear expansion, generally around 6×10-5/℃. Hence, epoxy products have stable size, small internal stress, and is not prone to cracking.

Good Processability

Epoxy resin basically does not produce low molecular weight volatile substances during curing, which allows it to be molded under low pressure or contact pressure. The flexibility of formula design is high, allowing it to meet various processing requirements with its formulations.

Good Electrical Properties 

Epoxy resin is one of the best thermosetting resins in terms of its dielectric property.

Good Stability

Epoxy resin that is free of impurities such as alkali or salt will not easily turn bad. As long as it is stored properly (sealed, moisture-free, and away from high temperatures), it can be stored for a year. If it still passes the quality test after exceeding the storage time, it can still be used. The cured epoxy products have excellent chemical stability and are more resistant to corrosion by various media such as alkali, acid, and salt than unsaturated polyesters and phenolic resins.

High heat resistance

The heat resistance of epoxy curing products is generally 80 to 100℃. Epoxy resin materials can have a heat resistance of up to 200℃ or more.

Best overall performance 

In thermosetting resins, epoxy resin and its cured products have the best overall performance.