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Title: Tannic acid-based prepolymer systems for enhanced intumescence in epoxy thermosets

Source: Journal, Green Materials

Author(s)Korey, Matthew ; Johnson, Alexander ; Webb, William ; Dietenberger, Mark ; Youngblood, Jeffrey ; Howarter, John

Publication Year: 2020  View PDF »

Category: Journal Articles
Associated Research Project(s):   FPL-4716-2A



Tannic acid (TA) is a bio-based high-molecular-weight organic molecule. Although biologically sourced, TA is a pollutant in industrial wastewater streams, and there is desire to find applications in which to downcycle this molecule. Many flame retardants (FRs) used in epoxy are synthesized from petroleum-based monomers. Various bio-based modifiers have been developed, but increasing the flame retardancy of the system without trade-offs with other properties has proved challenging. In this work, TA is incorporated into the thermoset. The molecular behavior of the system was dependent on the TA loading, with low concentrations causing the molecule to be surface-functionalized, while at higher concentrations the molecule was cross-linked into the network. The material was further characterized for its cross-link density, thermal stability, mechanical and thermomechanical properties and FR ability. In this work, TA was found to work well as an intumescent agent but did not reduce the heat release rate. The results of this study suggest that the external (hydrophilic surface-phenol groups) and internal (D-glucose and attached phenyl groups) structural regions of the TA molecule impact the FR ability of the molecule in epoxy separately. Maintaining the structural integrity of both regions is critical to the synergistic FR behavior of the molecule.

Keywords: Environmental impact; green polymers; sustainable materials

Publication Review Process: Formally Refereed

File size: 1,024 kb(s)

Date posted: 03/11/2021

This publication is also viewable on Treesearch:  view
RITS Product ID: 10123
Current FPL Scientist associated with this product
Dietenberger, Mark A.
Research General Engineer

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