Comparison of Different Bio-based Polymers for Electronic Substrates

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

“…To circumvent such limitations, lamination, 2,8,22 low-temperature soldering, 23 spin-coating, 24 drop-casting, 25 and printing (either inkjet or screen) of functional materials on the surface of the thermally sensitive PLA-based substrates have been proposed. 3,26,27 Replacement of critical metals (e.g., Cu, Ag, Au, Pt, Pd) and indium-doped tin oxide (ITO) is another challenge. Conductive polymers (e.g., polythiophenes, polyanilines, polypyrroles) can be considered as greener options for some applications; however, their inferior electrical and thermal properties compared to those of metals are limiting factors.…”

“…A tremendous and continuously increasing amount of electronics waste that mankind is generating (∼54 MT in 2019) results in a massive quantity of mostly nonbiodegradable and potentially hazardous hard-to-recycle junk of polymers and metals. , An additional problem is the growing share of fossil resources in plastic production, which is proposed to increase to 20% (from the current 4–8%) of total oil consumption by the mid of this century. − As of today, only ∼10% of all plastics are synthesized from renewables, from which practically an insignificant fraction is applied by the electronics industry despite its overall 15% share in the use of all produced polymers. − The dielectric substrates of printed circuit boards (PCBs) are mostly made of epoxy and phenolic resins based on fossil feedstock that leave a large CO 2 footprint (5.7–7.6 kg CO 2 per kg) . While the currently used PCBs such as FR-4 and FR-2 show excellent electrical, mechanical, chemical, and thermal properties, there is a broad range of applications, in which mechanical flexibility and often optical transparency are necessary; thus, polyethylene terephthalate, polyether ether ketone, polyimide, and other thermoplastics are often applied.…”

“…One way of alleviating the above problems is to substitute conventional polymers with bioplastics, as those may have end-of-life by biodegradation, do not require fossil resources, and are thus expected to have a smaller CO 2 footprint . While the properties of currently available biobased polymers are typically inferior compared to the technical polymers developed for electronics, these materials may find applications in low-cost short-life electronics produced and used in large volumes including mostly disposable devices such as RFID tags, sensors, medical kits, and so on. ,, Polylactic acid (PLA) is the most researched and known bioplastic that can be synthesized entirely from renewables and, depending on its use, it can be processed further to various shapes and forms by a number of different methods such as molding, extrusion, electrospinning, and three-dimensional (3D) printing. − While PLA and its derivatives have found good use in disposable packaging and biomedical applications, − their exploitation in electronics is less advanced because of the high thermal budgets of several classical manufacturing processes (e.g., chemical and physical vapor deposition of metals, reflow soldering of discrete components).…”

Refined Approach on Controlling Heat Transfer in a Vapour Phase Soldering Oven

“…The proposed method and setup is especially useful for special applications, such as pin in paste technology [14], or soldering on special, heat sensitive materials, such as biodegradables [15,16], which is a special current and future application of the presented solution.…”

Effect of PCB Thickness and Height Position During Heat Level Type Vapour Phase Reflow Soldering

“…The primary objective of this paper is to investigate the relation between the positioning height of the assembly inside the workspace and the thickness of the PCB in function of the temperature profile dynamics. The heating factor is widely used for calculations and evaluations [3,9,10] of soldering profiles and will be discussed later.Proper process control is not only necessary because of the assembling quality optimization, but for sensitizing the VPS process for lead-free soldering [11] on heat-sensitive materials, like biodegradable [12,13] printed circuit boards.…”