Proceedings of the SAMPE 2022 Conference and Exhibition
Cyanate ester resins are often blended with lower cost epoxy monomers in order to modify the cost, toughness, and processing characteristics. There are also several choices of catalysts that can be used to improve processing, namely by reducing the cure temperature. This study was undertaken to illustrate how a designed experiment approach can be used to systematically investigate a wide range of material combinations and illuminate the basic cure behavior of some simple cyanate ester – epoxy blend combinations. Two commercial cyanate ester resin products were obtained. Each was blended with a bisphenol F based epoxy resin at two different levels, and the effect of a hindered amine catalyst at low level was also investigated. This resulted in a 23 factorial experiment. Material characterization included differential scanning calorimetry (DSC) and thermal decomposition via thermogravimetric analysis (TGA). Although the addition of epoxy was expected to lower both the glass transition temperature and thermal stability (compared to pure cyanate), the designed experiment approach provided a good map of how these properties change as a function of epoxy substitution. For example, the amount of epoxy steadily decreased the Tg, TGA onset temperature, and char yield in an almost linear fashion from 0 to 50 wt%. Specifically, Tg was reduced by ~3°C per 1% epoxy, TGA onset temperature was reduced by ~1.2 °C per 1% epoxy, and char yield was reduced by ~0.5 wt% per 1% epoxy.
Copyright 2022 by the author. Used by the Society for the Advancement of Material and Process Engineering (SAMPE) with permission.
cyanate ester, cure. thermoset
Klosterman, Donald. "Preparation, Cure, and Characterization of Cyanate Ester-Epoxy Blends." SAMPE Conference Proceedings. Charlotte, NC, May 23-26, 2022. Society for the Advancement of Material and Process Engineering – North America.