Electrically conducting biodegradable polymer composites (polylactide‐polypyrrole and polycaprolactone‐polypyrrole) for passive resonant circuits

Abstract

Electrically conducting biodegradable polymer composites made of polypyrrole (PPy) nanoparticles embedded in poly(L‐lactide) (PLLA) or poly(ε‐caprolactone) (PCL) are prepared by chemical oxidative polymerization. They will be used as electrical conductors for fabricating biodegradable passive resonant circuits for bioimplants. For both composites, the conductivity exhibits a percolation threshold at ∼6 wt% of PPy. Several reactants are tested, the polymerization process resulting in the highest conductivity uses iron(III)chloride hexahydrate (FeCl3), sodium dodecyl benzene sulfonate, and p‐nitrophenol (pNPh), for both poly(L‐lactide)‐polypyrrole (PLLA‐PPy) and poly(ε‐caprolactone)‐polypyrrole (PCL‐PPy). Conductivities of 2.7 ± 0.8 S cmε1 (PLLA‐PPy) and 7.8 ± 2.3 S cm−1 (PCL‐PPy) are reached for a PPy content of 40 wt%. The PPy particle, observed by SEM, forms agglomerates having a size of 0.6–3.5 μm. The samples have similar PPy particle distributions over the entire cross sections. The conductivity as a function of time is investigated, being 34–70% of the initial value for samples stored in nitrogen, whereas it is less than 1% for samples stored in body‐like conditions, bringing the conclusion that a biodegradable packaging will be required to protect the resonant circuits from body fluids. Finally, the biocompatibility of the polymer composites is evaluated with cytocompatibility tests on dermal human fibroblast cells, showing promising results in particular for composites having a low PPy content. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

Biodegradable Polycaprolactone as Ion Solvating Polymer for Solution-Processed Light-Emitting Electrochemical Cells

“…The development of biodegradable substrates and electrodes, in recent years, demonstrates important and enabling results since these components represent the main bulk of the device567. These biodegradable devices will enable the use of electronic products that can decompose after their useful lifetime without a negative footprint on the environment8910.…”

Electroconductive Melt Electrowritten Patches Matching the Mechanical Anisotropy of Human Myocardium

“…Presence of Fe and Cl suggests a residual of by-products FeCl 2 and HCl that are formed from FeCl 3 and from the cations H+ coming from the dehydrogenation of the Py monomers. [47] Different areas of the coating showed a similar composition indicating a homogenous coating of PPy. The particle size distribution is shown in Figure 2e; ≈70% of the PPy particles was between 160 and 240 nm, median 193 nm.…”

“…This range agrees with the range of reported particle size of PPy, 40-250 nm. [47,48] The change in weight before and after the coating process is attributed to the mass of PPy. The average coating weight was 0.65 ± 0.12 mg for the squarepatch and 0.77 ± 0.15 mg for the auxetic patch (P = 0.0896), and an average coating thickness of ≈0.75 µm (754 ± 105 nm) determined by SEM images of focused ion beam (FIB)-milled sections ( Figure 2f).…”

Remote-controlled eradication of astrogliosis in spinal cord injury via electromagnetically-induced dexamethasone release from “smart” nanowires

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