Effect of molecular weight on mechanical properties and microstructure of 3D printed poly(ether ether ketone)

Abstract

Fused deposition modeling (FDM) has been successfully applied to the manufacturing of poly(ether ether ketone) (PEEK) special engineering plastics. However, due to the unavoidable defects caused by FDM technology and the high melt viscosity of PEEK, 3D printed PEEK parts have poor mechanical properties. In this study, the mechanical properties and microstructure of PEEK printed with different nozzle temperatures and having various molecular weights were researched in detail. The results showed that PEEK‐033G with medium molecular weight had good fluidity. With a nozzle temperature of 410 °C and using a high‐temperature chamber 3D printing system, the defects of 3D printed PEEK‐033G were reduced significantly, and the tensile strength and flexural strength could reach 96 and 115 MPa, which is close to the performance obtained using injection molding. In addition, the tensile strength in the Z‐axis direction was applied to characterize the interlayer bond strength. With a decrease of the viscosity of PEEK, an increase of interlayer bond strength ensued. It is expected that these findings could provide more insight for 3D printing of PEEK. © 2020 Society of Chemical Industry

The Role of Molar Mass in Achieving Isotropy and Inter-Layer Strength in Mat-Ex Printed Polylactic Acid

“…Similarly, Srinivas et al demonstrated for polylactic acid (PLA) that the interface stiffness itself can be improved by using an adequate enantiomeric composition and a multimodal molar mass distribution, including a fraction of low molecular weight species [ 29 ]. Along the same lines, in the study of poly-ether-ether-ketone (PEEK) printed samples, Xu et al showed that a reduction of molecular mass can increase fluidity, reduce internal defects and, consequently, significantly improve the mechanical properties of the printed product [ 30 ]. Moreover, by employing a trouser tear test, Vaes et al demonstrated that for nylon copolymers a decrease of the feedstock molar mass improved interlayer adhesion, due to the increased equivalent weld time [ 31 ].…”

An investigation of the microstructure and tribological behavior of polyether ether ketone composites fabricated by extrusion‐based additive manufacturing

“…5 Polyether ether ketone (PEEK) has attracted wide attention for fabricating lightweight parts by FDM-based AM technology owing to significant advantages, including strength-to-weight ratio, biocompatibility, excellent corrosion resistance and good wear resistance. 6 However, due to the semicrystalline nature of PEEK materials as well as the weak mechanical strength of 3D formed components caused by poor interlayer adhesion, it is still very challenging to fabricate high performance PEEK parts by FDM technology. 7 Extensive work has been conducted to enhance the strength of 3D printed PEEK materials via optimizing the main processing parameters, such as printing temperature, printing velocity, layer height, ambient and platform temperature as well as infill angle.…”

Effect of process parameters of fused deposition modeling on mechanical properties of poly-ether-ether-ketone and carbon fiber/poly-ether-ether-ketone

“…However, these materials are often used as demonstration parts since their lower glass transition temperature and poor mechanical properties do not satisfy the requirement of high temperature resistance fields like aerospace, bioengineering, and electronic appliances. 18 Poly-ether-ether-ketone is an interesting engineering polymer with a glass transition temperature of approximately 143°C and melting temperatures of 334°C, which is capable of working stably under conditions at temperatures of up to 260°C. 19 It is a good substitution metal because of its lightweight, non-toxic, high temperature resistance and mechanical strength, excellent impact and fatigue resistance as well as perfect biocompatibility.…”