New Epoxy Tougheners Widen the Adhesive-Formulating Window
Even with a greatly variable molecular structure, epoxies generally share adhesion to a wide range of substrates, resistance to a wide range of chemicals and excellent mechanical properties. Modification of epoxy-resin systems by additives, modifiers, fillers, plasticizers and other polymers offers vast opportunities to further customize the attributes of these materials. These positive attributes and easily varied structure allow formulators the opportunity to tailor a resin system's handling, cure behavior and cured performance over a tremendous range.
In contrast to flexibilized systems, elastomer-toughened epoxy systems generally maintain a large percentage of the modulus and temperature resistance of the unmodified resin system. They relieve stress by cavitation of the elastomer particles and shear banding in the cavitated zone4,5,6,7,8. Elastomer-toughened epoxy systems tolerate damage by preventing crack growth and thus limiting the damaged area.