Title: Synthesis & Characterization of a High-Performance Reversible Epoxy Curative

Authors: Levi Hamernik, Cecile Grubb, John Misasi

DOI: 10.33599/nasampe/s.21.0619

Abstract: Thermosetting materials exhibit numerous desirable properties and have been applied as the primary material for high-performance polymer matrix composites (PMCs). Recycling of these materials remains challenging as the nature of the covalent network prevents conventional solvent and thermal processes. Chemically reversible amine curatives based around the hexahydro-1,3,5-triazine (HHT) chemistry have been developed that allow for dissolution of an epoxy network under mild acidic conditions. Prior generations of these curatives have exhibited marginal thermal properties and lack appropriate working life for composite applications. This work reports the development of a next-generation HHT-based curative relying on phenol functionality for crosslinking. DGEBA epoxy networks incorporating this novel curative are characterized by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and dynamic mechanical analysis (DMA). Network degradation behavior in acetic acid was studied to assess recyclability. This network exhibits marked improvements in thermomechanical properties over prior amine-based HHT curatives, while retaining desirable decomposition characteristics. Networks crosslinked with similar phenol curatives without HHT moieties did not exhibit acid degradation behavior.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000619

Pages: 14

Price: FREE