Title: Fast Cure of Vacuum Bag Only Prepreg Composites

Authors: David B. Bender, Timotei Centea, and Steve R. Nutt

DOI: 10.33599/nasampe/c.19.0733

Abstract: High performance composites utilization has been limited by their expensive and slow manufacturing processes. To address the need for increased efficiency in high performance composites processing, a novel vacuum bag only (VBO) prepreg was designed, modeled and tested in this work. The prepreg has characteristics that make it suitable for shorter cure cycles while retaining high quality performance. A key enabling factor in this prepreg is through thickness air permeability which allows air to evacuate faster than in traditional edge breathing VBO prepregs. This is achieved by a discontinuous resin distribution on the surface of the prepreg. Another key feature in this prepreg is the vinyl hybrid resin employed, which represents a new class of fast cure cycle resins. The resin was characterized using DSC to create a new model that can represent this class of resins. The model enabled much closer fit to experimental cure cycle data through the inclusion of a new term to represent the inhibition of the resin until a threshold temperature is reached. This new model was then employed to create optimized cure cycles that minimized cycle times. Microstructural quality and glass transition temperature were assessed and compared to appropriate controls. Void-free parts were possible with much shorter cure cycles than conventional cure cycles. The glass transition temperature of these samples were also comparable to samples with conventional cure cycles demonstrating full cure during processing. The results from this study show that with proper design, faster cure cycles are possible.

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Conference: CAMX 2019

Publication Date: 2019/09/23

SKU: TP19-0733

Pages: 15

Price: $30.00