Huntsman Advanced Materials manufactures products that are used in epoxy resin systems. Epoxy resin systems consist of two parts, an “A” and a “B” side. The B side, also known as the “hardener”, is the epoxy curing agent; the curing agent is responsible for reacting with the epoxy groups contained in the epoxy resin A side. Reaction of curing agents with epoxy resins results in hard, thermoset materials. These thermoset materials are often used as coatings and as components in finished goods, like adhesives or composites.
The type of epoxy curing agent influences both the curing characteristics of an epoxy resin system as well as the final thermoset performance. Curing characteristics include items such as pot life and thin film cure speed, while thermoset performance includes items such as hardness, glass transition temperature, and tensile strength. Below is an overview of the types of epoxy curing agents that Huntsman Advanced Materials manufactures:
Polymercaptan Curing Agents
Huntsman Advanced Materials is the global leader in the manufacturing of polymercaptan epoxy curing agents offering a broad range of products to meet end user needs. With unrivaled green strength development, polymercaptans are well suited for time critical applications. Polymercaptan cure speeds can be tuned to be as fast as 30 seconds (gel time), or as long as 30 minutes (gel time). Polymercaptan curing agents are known to exhibit reduced cure temperature dependence; this makes polymercaptans especially valuable in small scale applications and with applications at low temperatures.
Polyamide and Amidoamine Curing Agents
Polyamides and amidoamine epoxy hardners are based on a backbone of aliphatic chains connected via amide linkages. This unique backbone imparts toughness into the final thermoset; this toughness translates into observed performance increases in items such as impact resistance, crack resistance, and substrate adhesion.
Polyamide and amidoamine agents differ mainly in their respective viscosities; polyamides are much more viscous than amidoamines. Both curing agents offer excellent water resistance in the final thermosets. Excellent water resistance, combined with toughness, make polyamide and amidoamine curing agents preferred choices in applications such as adhesives, primer coatings, moisture barrier coatings and electrical potting.
Amine Curing Agents
Many epoxy curing agents used today are of the amine variety. Amine curing agents are widely employed due to their practical curing speeds and final thermoset performance. There are three main types of amine curing agents:
Phenalkamine Curing Agents
Phenalkamine curing agents are based on a backbone of bio-renewable cardanol. Owing to this cardanol derived backbone, phenalkamines have similarly excellent water resistance and toughness to that of polyamides and amidoamines; phenalkamines, however, have improved low temperature curing performance. This increased low temperature curing performance makes phenalkamines popular in outdoor coating applications as it allows for longer application seasons in cold climates. Common applications include marine coatings, industrial primers, and moisture barrier coatings.