Bioplastics and Carbon-Based Sustainable Materials, Components, and Devices: Toward Green Electronics

Abstract

The continuously growing number of short-life electronics equipment inherently results in a massive amount of problematic waste, which poses risks of environmental pollution, endangers human health, and causes socioeconomic problems. Hence, to mitigate these negative impacts, it is our common interest to substitute conventional materials (polymers and metals) used in electronics devices with their environmentally benign renewable counterparts, wherever possible, while considering the aspects of functionality, manufacturability, and cost. To support such an effort, in this study, we explore the use of biodegradable bioplastics, such as polylactic acid (PLA), its blends with polyhydroxybutyrate (PHB) and composites with pyrolyzed lignin (PL), and multiwalled carbon nanotubes (MWCNTs), in conjunction with processes typical in the fabrication of electronics components, including plasma treatment, dip coating, inkjet and screen printing, as well as hot mixing, extrusion, and molding. We show that after a short argon plasma treatment of the surface of hot-blown PLA-PHB blend films, percolating networks of single-walled carbon nanotubes (SWCNTs) having sheet resistance well below 1 kΩ/□ can be deposited by dip coating to make electrode plates of capacitive touch sensors. We also demonstrate that the bioplastic films, as flexible dielectric substrates, are suitable for depositing conductive micropatterns of SWCNTs and Ag (1 kΩ/□ and 1 Ω/□, respectively) by means of inkjet and screen printing, with potential in printed circuit board applications. In addition, we exemplify compounded and molded composites of PLA with PL and MWCNTs as excellent candidates for electromagnetic interference shielding materials in the K-band radio frequencies (18.0−26.5 GHz) with shielding effectiveness of up to 40 and 46 dB, respectively.

Lignin as a High-Value Bioaditive in 3D-DLP Printable Acrylic Resins and Polyaniline Conductive Composite

“…In the field of electronics, lignin has been widely investigated [ 11 , 12 , 16 , 17 , 18 , 19 , 20 , 21 , 22 ] for the manufacture of energy storage devices [ 22 ], electromagnetic shielding [ 16 , 17 ], organic cathodes [ 11 ], as a natural binder or even as a dopant in conductive polymers for the production of electrochemical capacitors or supercapacitors [ 12 , 18 , 19 , 20 , 21 ]. Due to the redox activity of the quinone/hydroquinone moieties, lignin derivatives effectively enhanced the capacitance of intrinsically conductive polymers, including poly(3,4-ethylenedioxythiophene), polypyrrole, and polyaniline (PANI) [ 23 ] as well as carbon-based materials such as graphene [ 19 ].…”

Self‐Healing and Electrical Properties of Viscoelastic Polymer–Carbon Blends

“…and metals, which require proper recycling to avoid environmental pollution. [3,4] On the other hand, nature shows that living organisms can fight for survival against injuries, by repairing damaged tissues through selfhealing. This ability of living organisms inspired scientists to develop materials, which are able to heal cracks after failure.…”

Toward Sustainable Wearable Electronic Textiles

“… 190 − 193 Furthermore, virtually any known form of applicable conductive carbons can be formed from renewables. 193 Therefore, the use of carbon-based conductive materials is considered to the “greener” option than metals. However, the electrical conductivity of carbon-based materials is not as significant as metals, even though CNTs are an example of the most promising materials for wearable electronics offering metallic-like and superconductive electron transport 194 and can be modulated under several forms of stimulation.…”