Title: The Pitfalls of Post-Cures: Investigating the Overlap of Between Cure and Degradation in Polybenzoxazine Networks

Authors: Benjamin L.G. Morasch, Keith Dusenberry, Jeffrey S. Wiggins

DOI: 10.33599/nasampe/c.24.0366

Abstract: Polybenzoxazines are an attractive alternative to traditional thermosetting chemistries used in the aerospace industry including epoxy and phenolic resins for applications including coatings, adhesives, composites, and flame-retardant materials due to their high thermal stability, high glass transition temperatures, and modularity in molecular design. In the preparation of thermoset composite parts, an often overlooked consideration is the structural development of the polymeric networks during the curing and post-curing steps. Too low of a cure temperature could be inadequate to drive complete conversion, and too high of a cure/post-cure temperature could result in the loss of small molecules and the formation of an irregular network. We propose that the polymerization pathway is more complicated than often granted, and that the intentional selection of thermal treatment steps are essential to maximize final network properties. Herein, we report a detailed examination of benzoxazine structural evolution during polymerization followed by assessments of the resulting thermomechanical properties of the cured networks to consider any detrimental effects of extraneous thermal treatments. Utilization of multiple structural analyses will provide insightful characterization of network progression during thermal treatments. This research seeks to establish the role of cure and post-cure treatments in polybenzoxazine networks to guide the design of optimized thermoset composites.

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Conference: CAMX 2024 | San Diego CA

Publication Date: 2024/9/9

SKU: TP24-0000000366

Pages: 9

Price: $18.00