Page 10 - IJAMD-1-2

International Journal of AI for
Materials and Design
Sustainable electronics using AI/ML

Typically, Mg and Zn exhibit fast transient behavior in a similar chemical structure to PLA; however, the lack of
deionized water and biological solutions, while W and Mo methyl side group enables the polymer chains to pack tightly
display gradual but foreseeable rates of degradation. These and yields a high gas barrier, high mechanical strength,
behaviors offer diverse alternatives to fulfill the demand high thermal stability, and a high degree of crystallinity.
of degradation spans for varied applications. W and Mo Besides, PGA is more susceptible to degradation than
can be employed for slow transient applications, such as PLA due to its higher hydrophilicity. However, due to their
medical devices that need metals to directly interact with high processing temperature, it is difficult to melt-mix
biological tissues for signal detection, because of their them with other commercial biopolymers including PCL,
purposeful and controlled rates of degradation. Mg and polybutylene succinate, and polyhydroxybutyrate as well
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Zn can be considered for applications requiring temporary as biomass-based polymers such as cellulose and starch.
functionality due to their rapid degradation, such as secure The next well-studied polymer in transient electronics
electronics that need to disappear within a defined, limited is PLGA, a hydrophilic polymer with a high degree of
time frame. 4 biocompatibility. It is composed of PLA and PGA that can
be controllably degraded by tailoring the molecular weight
3.2. Polymers and the ratio of its components. The next one is PCL,
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Two categories of biodegradable polymers are distinguished which is a synthetic linear polyester. This semi-crystalline
based on their origin: natural polymers, derived from polymer has a relatively lower degradation rate than
renewable and natural resources; and synthetic polymers, either PGA or PLA. Yet another polymer is PVA, holding
which are produced from petroleum oil. The categorization several benefits, such as non-toxicity, non-carcinogenic
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of biodegradable polymeric materials, both natural and nature, and the ability to dissolve in various solvents. In
synthetic is presented in Figure 2. 13 comparison to PCl, PVA has a more rapid dissolution and
degradation process. The solubility of PVA in water is
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3.2.1. Natural polymers primarily determined by the degree of polymerization and
Cellulose and silk as natural polymers demonstrate the temperature of the solution. In addition, a noteworthy
significant potential as non-toxic and biodegradable report demonstrated the tailoring of PVA dissolution rate
substances for transitory electronics. Cellulose-based by altering the composite structure. 21
materials, in particular, exhibit exceptional degrading Generally, for both natural and synthetic biodegradable
capabilities, favorable biocompatibility, superior polymers, the degradation is influenced by the
performance, and cost-effectiveness, hence showcasing physicochemical characteristics of the polymer, such
significant prospects for environmentally sustainable mass as its molecular weight, crystallinity, the presence of
production of electronics. Starch as a polysaccharide hydrolyzable bonds, and surface area. In addition, various
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with a granular form has the advantages of affordability, environmental factors play crucial roles, including
abundance, and renewability, which make it a desirable temperature, pH, humidity, oxygen availability, and
material for manufacturing biodegradable polymers for ultraviolet light exposure. The process is further impacted
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the application of flexible disposable organic electronics. by the presence and activity of specific microbial degraders
Gelatin is another natural polymer extracted by thermal that produce extracellular enzymes to catalyze the
hydrolyzing of collagen, typically used in the food industry degradation of the polymer. 22
processes due to its good functional qualities. 15
3.3. Semiconductors
3.2.2. Synthetic polymers The performance of electronic devices heavily relies on
In addition to green polymers discussed above, synthetic quality and characteristics of the semiconducting materials,
polymeric materials have also been reported as promising making them a crucial element in the field of electronics.
candidates demonstrating non-toxicity and biodegradability Notably, the ever-decreasing demand in degradable
properties for transitory electronics. These polymers are electronics has motivated several research endeavors to
substituted or incorporated by adding hydrophilic groups study the degradability of different electronic components
to their backbone, allowing them to disperse, swell, or in a material perspective including silicon-based
dissolve in water. The hydrolytically degradable polymers semiconductors, metal oxides, organic semiconductors
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that have been extensively studied comprise poly (glycolic (OSs), and dielectrics.
acid) (PGA), PLA, poly-lactic-co-glycolic acid (PLGA),
polycaprolactone (PCL), and poly (vinyl alcohol) (PVA), 3.3.1. Silicon-based semiconductors
which are shown in Figure 2. 16-18 PGA is one of the most The remarkable progress in silicon technology has spurred
promising biodegradable polymers available today. It has extensive research into degradability studies, with findings

Volume 1 Issue 2 (2024) 4 doi: 10.36922/ijamd.3173