Exploiting mono‐ and hybrid nanocomposite materials for fused filament fabrication with acrylonitrile butadiene styrene as polymer matrix

Abstract

Acrylonitrile butadiene styrene (ABS) based polymeric composites consisting of mono‐ and hybrid nano‐compounds, that is, graphene nanoplatelets (GNP's), multi‐walled carbon nanotubes (CNT's), and titanium dioxide (TiO2), are studied for fused filament fabrication (FFF). Rheological analysis in a screening step reveals that nanocomposites containing CNT result in a better nano‐filler dispersion within the matrix and enhanced matrix interaction. The addition of GNP and TiO2 leads to a better coalescence between the deposited filaments. For the actual FFF specimens, emphasis is on the tensile, flexural and impact properties as well as the void content. It is shown that the joint addition of GNP, CNT, and TiO2 gives rise to a remarkable synergistic effect, leading to an improved dispersion and an increased tensile modulus and strength of 3D printed ABS by 16 and 20%. Decreasing the layer thickness increases the mechanical properties of the materials, while the printing temperature does not lead to major variations of the mechanical properties, due to a dominant effect of the addition of nanoparticles. It is also shown that for well‐designed composites the slower sintering and higher void content is overruled by the reinforcement effect.

Enhancing the Strength of Acrylonitrile–Butadiene–Styrene with Gas-Phase-Synthesized Graphene for Injection-Molding Applications

“…6−18 However, graphene flakes derived from graphite have several drawbacks that have limited the performance of the nanomaterials in polymers, including defects, multiple graphene layers, and a propensity to aggregate and restack in polymer matrices. 1,[3][4][5][6][7][8][9][10]20,21 Exfoliating bulk graphite into graphene powder also typically requires hazardous chemicals that give rise to liquid waste that is detrimental to the environment, 1,2,10,22 which makes the sustainable mass production of GNCs a challenge. High-quality and aggregation-resistant graphene sheets created through environmentally friendly processes are still needed for the large-scale manufacturing of injection-molded GNCs.…”

“…ABS–GSG nanocomposites exhibited an average stress at break that was 19.0% higher than that of pure ABS (Figure b), which indicates that GSG continuously reinforced ABS until the specimens fractured. The drastic increase in the strength of ABS with a GSG content of only 0.1 wt % was an unexpected result because filler loadings of at least 1.0 wt % are generally required to achieve similar improvements in ABS containing GO, RGO, or GNP. ,,− The surprising strength of ABS–GSG nanocomposites motivated an investigation into the relationships between filler structure, filler–matrix interfaces, and tensile properties of ABS–GNP and ABS–GSG nanocomposites.…”

“…Furthermore, flat platelets can restack into graphite due to van der Waals forces, − ,, which prevents polymer chains from interfacing with individual graphene layers . Strategies for mitigating the aggregation and restacking of graphene in ABS include the use of surface treatments, ,− , rod-shaped fillers, , and dopants . The GNP flakes used in this study were unmodified.…”

“…Graphene is a single layer of covalently bonded carbon atoms with remarkable mechanical properties that can be harnessed to strengthen polymers. − Graphene-filled polymer-matrix nanocomposites (GNCs) continue to generate extraordinary interest in the scientific community, as evidenced by the thousands of reports on the topic that were published over the last three years alone (Figure S1). Research into GNCs has been facilitated by the wide availability of graphene manufactured through the exfoliation of graphite (Figure S1) such as graphene oxide (GO), reduced graphene oxide (RGO), and graphene nanoplatelets (GNP).…”

“…Enhancing the strength-to-weight ratio of acrylonitrile–butadiene–styrene (ABS) can significantly benefit society because the engineering thermoplastic is widely used in the injection molding manufacturing of automotive parts, aircraft components, and consumer electronic devices. − The mechanical properties of ABS have been enhanced by reinforcing the plastic with GO, RGO, and GNP. − However, graphene flakes derived from graphite have several drawbacks that have limited the performance of the nanomaterials in polymers, including defects, multiple graphene layers, and a propensity to aggregate and restack in polymer matrices. ,− ,, Exfoliating bulk graphite into graphene powder also typically requires hazardous chemicals that give rise to liquid waste that is detrimental to the environment, ,,, which makes the sustainable mass production of GNCs a challenge. High-quality and aggregation-resistant graphene sheets created through environmentally friendly processes are still needed for the large-scale manufacturing of injection-molded GNCs.…”