What is the reaction mechanism of HAA curing agent and how does it affect the final performance of the resin?

1. Reaction mechanism
Composition of HAA curing agent: HAA (β-hydroxyalkylamide) curing agent is usually composed of hydroxyl and amide groups, which enable it to chemically react with functional groups in polyester resin.
Curing process:
Cross-linking reaction: Under heating or through the action of catalyst, HAA curing agent reacts with carboxyl or hydroxyl groups in polyester resin to form a cross-linked structure. This process usually involves a dehydration reaction to generate new amide chains, thereby improving the strength and stability of Polyester Resins For HAA Based Formulations.
Low temperature curing: The high reactivity of HAA curing agent enables the curing process to be carried out at lower temperatures, usually in the range of 120-150°C, which helps save energy and reduce the risk of damage to heat-sensitive substrates.
2. Impact on final performance
Weathering resistance:
HAA-cured polyester resins show good weathering resistance in outdoor environments, including UV resistance, oxidation resistance and moisture resistance. This allows the coating to maintain its performance under conditions of exposure to sunlight, rain and temperature changes.
Adhesion:
HAA curing agent can form a good chemical bond with the substrate, improve the adhesion of the coating, and reduce the risk of shedding and peeling. Good adhesion is the key to ensure long-term use.
Mechanical properties:
The cross-linked structure makes the cured resin have higher mechanical strength and toughness, can resist impact and wear, and extend the service life.
Chemical stability:
HAA-cured polyester resin has good resistance to a variety of chemicals (such as solvents, acids and alkalis), and is suitable for use in industrial environments.
Low toxicity and low irritation:
Compared with TGIC curing agent, the low toxicity and low irritation of HAA curing agent make it safer to operate, have less impact on the environment and human health, and meet modern environmental protection requirements.