Title: High Velocity Impact of Toughened Epoxy Resin Systems in Glass Fiber Reinforced Composites

Authors: Brendan A. Patterson, Casey Busch, Daniel B. Knorr, Jr.

DOI: 10.33599/nasampe/s.21.0609

Abstract: Toughening mechanisms of different polymer resins were explored for fiber reinforced composites under high velocity impact testing. Previous research demonstrated the critical importance of polymer molecular architecture and temperature-dependent viscoelastic behavior on impact performance by altering the damage mechanisms observed in both polymer-only and fiber reinforced composite testing. Combining these aspects creates a design space for performance optimization, particularly for reducing damage area due to delamination while retaining energy absorption over a broad range of temperatures. Epoxy resins that were either rubber toughened or intrinsically tough (i.e., a nanoscale phase‐separated epoxy) were used to fabricate fiber reinforced composites with plain weave S-2 glass fibers using VARTM. The resulting composites were tested under high velocity impact over a temperature range of -50°C to 75°C and were compared to composites made from conventional, non-toughened epoxy resins. Overall, the total energy absorption stayed fairly constant for each toughened resin system over the temperature range of interest and were comparable from system to system. The damage area, however, decreased by more than 50% for the phase separated epoxy relative to the rubber toughened system, because of a change in deformation mechanism. The change in damage area without a decrease in total energy absorption implies that composite deformation mechanisms can be tailored by rational design of the polymer matrix molecular architecture to improve high-rate impact performance of fiber reinforced composites.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000609

Pages: 9

Price: FREE