A new liquid dicyanate ester monomer, which cures to produce a high-Tg amorphous thermosetting polycyanurate glassy material, is being commercially introduced in 1990 for use in structural composite, adhesive, coating and electronic applications. The cure of this monomer and its effects on the macroscopic properties of the polycyanurate material are investigated. Preliminary work has demonstrated that the reaction of the dicyanate ester to form polycyanurate materials is complex. A one-to-one relationship between Tg and conversion exists allowing Tg to be used as the primary parameter for monitoring cure. Kinetically-controlled master curves are constructed for both uncatalyzed and catalyzed systems and show that the onset of diffusion-control occurs in the rubbery regime well before vitrification. Evidence of the effects of various cure reaction mechanisms and competing reactions is presented. An unusual response of the cured material to continuous thermal cycling, in which Tg and rigidity above Tg decrease and then subsequently increase over the course of a month, is observed.
|Number of pages||5|
|Journal||Polymeric Materials Science and Engineering, Proceedings of the ACS Division of Polymeric Materials Science and Engineering|
|State||Published - 1990|
|Event||Proceedings of the ACS Division of Polymeric Materials: Science and Engineering - Boston, MA, USA|
Duration: Apr 1 1990 → Apr 1 1990