Title: Crystallinity Variability in Thick Section PET Composites

Authors: Jacob A. Reinholz, Luke R. Gibbon, Eric S. Hall, Robert J. Hart, Chad A. Ulven

DOI: 10.33599/nasampe/c.23.0213

Abstract: Thermoplastic polymer crystallinity is partially dependent on processing parameters during the molding process. Crystallinity can be altered by temperature, pressure, and heat transfer rates during the processing of thermoplastic composites. Compression molding is a popular technique for rapid manufacturing of thermoplastic and glass fiber reinforced composites. During the compression molding of the thick sectioned polyethylene terephthalate (PET) composites, crystallinity and resulting properties can be altered not only globally but also through thickness. Given the low thermal conductivity of composites utilizing PET and glass fibers, the heat cycle from the surface to the interior of the panel are significantly different thereby directly affecting the mechanical properties of the PET and subsequent composite. This study isolates different processing parameters on thin section panels and expands that understanding to thick section layer wise study of crystallinity. Understanding the variation of mechanical properties through thickness allows for the optimization of properties and more accurate finite element modeling of structures designed with these types of composites in mind. Mechanical characterization included tensile, flexural, interlaminar shear, and compression properties. Crystallinity was characterized utilizing Differential Scanning Calorimetry (DSC) and all specimens were post processed with a waterjet eliminating the heat affected zone of traditional specimen preparation techniques.

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Conference: CAMX 2023

Publication Date: 2023/10/30

SKU: TP23-0000000213

Pages: 13

Price: $26.00