3D Printable Sustainable Composites with Thermally Tunable Properties Entirely from Corn-Based Products

Abstract

Renewable and biodegradable composites derived from natural resources are receiving increasing attention for sustainable manufacturing. Developing eco-friendly and robust biocomposites can alleviate health and environmental concerns associated with the reliance on petroleum-based plastics. Here, we develop a sustainable composite, made entirely from corn products and waste, and investigate a thermally strengthened mechanism for tunable mechanical properties. A two-step chemical process is used to extract cellulose fibers from corn husks and distribute them in corn starch-derived matrices to develop 3D printable biocomposites. Ink preparation is tailored with water content and thermal treatment to achieve desired rheological properties for direct ink writing. By harnessing a thermally controlled hydrogen bonding mechanism between matrix and fibers, the printed samples have tunable mechanical properties up to 3.3 fold. The chemical interactions among amylopectin molecules also result in different porous microstructures, leading to lightweight composites. The composites purely from biomass and waste are a new class of additively manufacturable sustainable materials that can be used as alternatives to petroleum-based plastics in engineering applications and in the fields of medicine and the food industry.

Boosting Piezoelectricity by 3D Printing PVDF‐MoS2 Composite as a Conformal and High‐Sensitivity Piezoelectric Sensor

“…[29,31] Therefore, 3D printing inks should meet specific requirements such as shear thinning and yielding properties within a reasonable range of yield strength for their printability. [29,[31][32][33]37] In light of this requirement, the rheology of PVDF and PVDF-MoS 2 ink was carefully tailored with N-Methyl-2-pyrrolidone (NMP) to enable successful 3D printing. During 3D printing, the extruded ink exerted by a shear stress at the nozzle and then turns into a solid-like material to retain its shape after deposition.…”

“…During 3D printing, the extruded ink exerted by a shear stress at the nozzle and then turns into a solid-like material to retain its shape after deposition. [31][32][33]37] Figure 1f and Figure S2a (Supporting Information) present the shear-yielding behavior of the PVDF and PVDF-MoS 2 composites, demonstrating a transition between gel-like and fluid-like behaviors. The storage modulus (G′) and loss modulus (G′′) of the PVDF and PVDF-MoS 2 composite inks are compared in Figure 1f to shear stress.…”

Additive Manufacturing Using Agriculturally Derived Biowastes: A Systematic Literature Review

“…Using biowastes in printable filaments, pastes/gels/inks, and powders can reduce the cost of printed products and also increase their sustainability and biodegradability [51]. However, integrating biowastes into filaments or inks for 3D printing can give rise to certain challenges and difficulties, including altering material properties, potentially affecting the filament's mechanical and thermal characteristics [30,40,42,48,58,68,69]. This alteration can impact print quality, resulting in reduced strength, increased brittleness, or changes in dimensional stability.…”

Biodegradable Polyurethane Derived from Hydroxylated Polylactide with Superior Mechanical Properties

“…However, the recycling of waste plastics is challenging and often not cost-effective [11]. Due to the continuous increase in fossil energy consumption and the growing awareness of environmental protection, renewable biodegradable materials are becoming increasingly important as alternatives to petroleumbased plastics for the sustainable development of industry and human society [12,13]. High-performance biobased polyurethanes (Bio-PUs) have a wide range of applications, including electronic devices [14,15], tissue engineering [16][17][18], agricultural film [19], express packaging [20], food packaging and other fields [21][22][23].…”