Rheology, Crystallinity, and Mechanical Investigation of Interlayer Adhesion Strength by Thermal Annealing of Polyetherimide (PEI/ULTEM 1010) Parts Produced by 3D Printing

Abstract

Fused deposition modeling (FDM) is a 3D printing technology in which the melt extrusion method is used for the production of thermoplastic parts. 3D printed thermoplastic materials produced by this method suffer from a particularly significant problem, however, namely poor interfacial bond formation that results in weak mechanical performance. This work proposes a thermal process to enhance the strength of the interlayer adhesion of 3D printed PEI thermoplastic materials. The annealing process was determined as a suitable post-processing procedure and was the focus of this work. Annealing was carried out in an oven at temperatures of 220, 225, 230, and 235 °C; it was determined that annealing performed at 225 °C in particular was highly desirable in terms of enhancing interlayer adhesion strength. In this work, characterization (FTIR, XRD, and SEM) and mechanical (tensile, bending, and hardness) analyses of 3D printed PEI were performed to better understand the strength of interlayer adhesion and overcome a mechanical performance limitation of this material. According to the tensile, bending, and hardness test results, the greatest improvements were found as increase of 10, 5, and 12%, respectively.

Demonstration of High Detoxification Efficiency of Glassy Polymer–Metal Hydroxide Composites toward Chemical Warfare Agent Simulants

“…The imide cross-linking of Ultem made it thermally resistible to high heat exposure. 38,40 Upon the addition of Zr(OH) 4 , the residual weight at 800 °C increased, as expected, but such an increase was not proportional to the amount of the Zr(OH) 4 added due to the thermal instability of the hydroxyl group of the Zr(OH) 4 . The estimated amounts of Zr(OH) 4 added to the composite were 50, 105, and 205 mg/g for 8%-Zr(OH) 4 @Ultem, 20%-Zr(OH) 4 @Ultem, and 30%-Zr(OH) 4 @Ultem, respectively.…”

“…The x-Zr(OH) 4 @Ultem FTIR spectra showed a new absorbance at 3350 cm −1 resulting from the hydroxyl group stemming from the Zr(OH) 4 added to the polymer matrix. 38 Moreover the suppression and partial shift of the C�O group in x-Zr(OH) 4 @Ultem can be due to complexation of the C�O with Zr to form Zr−C�O. The back-bonding mechanism shown in Scheme 1 explained the bond interaction between Zr(OH) 4 and Ultem.…”

Thermal post‐processing effects on the polycarbonate acrylonitrile butadiene styrene composites manufactured by fused filament fabrication

“…[ 31 ] The crystallinity of PLA increased to 25% after the slow‐cooled annealing process and fracture toughness was doubled after quenching. The impact of annealing on 3D‐printed polyetherimide was investigated by Yilmaz et al [ 32 ] Annealing at 225°C enhanced the hardness, tensile strength, and bending strength by 12%, 10%, and 5%, respectively. The heat treatment process resulted in better interlayer adhesion.…”

Investigating the effect of printing conditions and annealing on the porosity and tensile behavior of 3D‐printed polyetherimide material in Z‐direction

“…Polyetherimide was chosen for this study because of its combination of high mechanical, thermal, and chemical performances, making it a favorite material beside PEEK and PEKK for various fields such as aerospace, aeronautic, and defense. Yilmaz et al 24 studied only the effect of annealing to enhance the strength of the interlayer adhesion of 3D printed PEI. However, the aim of our study is to investigate the effect of printing speed, nozzle temperature as key process parameters in FFF/FDM technology, and the effect of heat treatment (annealing) on tensile and physical properties of ULTEM 1010 parts printed in the Z-direction.…”