Toughening of engineering thermosets via new toughening mechanisms

It is always a challenge to be able to toughen an engineering thermoset without concurrently sacrificing other important properties, such as modulus and creep resistance. The recent technological advancement at Dow has enabled us to design engineering thermosetting systems with high toughness/toughenability, high Tg, high modulus, low moisture absorption, great processability, and, most importantly, low cost to produce. To obtain the above desirable properties, novel approaches which involve the control of thermoset network structure and/or use of appropriate rigid toughener particles have to be introduced. The present paper, as a result of the above effort, focuses on introducing new toughening mechanisms we have observed in a variety of engineering thermosets. These new mechanisms include crazing and dilatation band formation. The possible cause(s) and conditions resulting in the formation of these unusual mechanisms are discussed. The importance of the present findings for toughening high performance thermosets is also addressed.

Toughening of engineering thermosets via new toughening mechanisms Conference Paper