# Polylactic Acid/Carbon Nanoparticle Composite Filaments for Sensing
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Plasticizer** & **Filler** & **Processing Method** & **Reference** \\ \hline \multirow{2}{*}{Tributyl 2-acetyl citrate} & Bi\({}_{0.5}\)Sb\({}_{1.5}\)Te\({}_{3}\) & \multirow{2}{*}{Melt extrusion} & [17] \\  & MWCNT & & \\ \multirow{2}{*}{PEG (M\({}_{\text{W}}\) 200 g\(\cdot\)mol\({}^{-1}\))} & Reduced graphene & \multirow{2}{*}{Batch mixing} & [18] \\  &oxide & & \\ \multirow{2}{*}{Epoxidized soybean oil} & MWCNT & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{Acid treated MWCNT} & \multirow{2}{*}{Two-roll mill} & [19] \\  & & & \\ \multirow{2}{*}{(M\({}_{\text{W}}\) 950–1050 g\(\cdot\)mol\({}^{-1}\))} & \multirow{2}{*}{Anoplatelets} & \multirow{2}{*}{
\begin{tabular}{c} Batch mixing \\ and compression \\ molding \\ \end{tabular} } & \multirow{2}{*}{[20]} \\  & & Mel extrusion & \\ \multirow{2}{*}{(M\({}_{\text{W}}\) 2000 g\(\cdot\)mol\({}^{-1}\))} & \multirow{2}{*}{SWCNT} & \multirow{2}{*}{and compression} & [15] \\  & & & \\ \multirow{2}{*}{Triaectin} & \multirow{2}{*}{Fax fiber} & Mel extrusion & [21] \\  & & Mel extrusion & \\ \multirow{2}{*}{Poly(butylene} & \multirow{2}{*}{Rami fiber} & \multirow{2}{*}{and compression} & [22] \\  & & & \\ \multirow{2}{*}{Epoxidized linseed oil} & \multirow{2}{*}{Hazelnut shell flour} & Mel extrusion & [16] \\  & & CaCO\({}_{3}\) Halloysite & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{nontubes} & \multirow{2}{*}{Mel extrusion} & [23] \\  & & LAK 301 & \\ \multirow{2}{*}{(M\({}_{\text{W}}\) 6000 g\(\cdot\)mol\({}^{-1}\))} & \multirow{2}{*}{Micro-sized talc} & \multirow{2}{*}{} & \\  & Bamboo & & \\ \multirow{2}{*}{Glycerol} & \multirow{2}{*}{(different forms)} & \multirow{2}{*}{Batch mixing} & [24] \\  & & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{ZnO} & \multirow{2}{*}{Solvent cast} & [25] \\  & & & \\ \multirow{2}{*}{Acetyl triethyl citrate} & \multirow{2}{*}{Montmorillonite} & \multirow{2}{*}{Mel extrusion} & [26] \\  & & layered silicate & \\ \multirow{2}{*}{Diglycerine tetraacetate and} & Sodium & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{Montmorillonite and} & \multirow{2}{*}{Milling and injection} & [27] \\  & & organolcays & \\ \multirow{2}{*}{(M\({}_{\text{W}}\) 1000 g\(\cdot\)mol\({}^{-1}\))} & \multirow{2}{*}{Montmorillonite} & Mel extrusion & [28] \\  & & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{Montmorillonite} & \multirow{2}{*}{and compression} & [29] \\  & & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{Organoclay} & \multirow{2}{*}{micinjection} & [30] \\  & & & \\ \multirow{2}{*}{PEG} & \multirow{2}{*}{Melt extrusion} & [31] \\  & & & \\ \multirow{2}{*}{(M\({}_{\text{W}}\) 400 g\(\cdot\)mol\({}^{-1}\)) and Tributyl & \multirow{2}{*}{Nanosized CaCO\({}_{3}\)} & Mel extrusion & [31] \\ \multirow{2}{*}{Citrate} & \multirow{2}{*}{Halloysite nanolaxy} & Solvent casting & [32] \\ \multirow{2}{*}{Methoxy polyethylene glycol} & Silica & Batch mixing & [33] \\  & & & \\ \end{tabular}
\end{table} 
Table 1: Polylactic acid (PLA) composite systems with different plasticizers and fillers. PLA nanocomposites produced with carbon nanotubes (CNT) showed improved dispersion of CNT upon addition of a plasticizer, enabling the preparation of electrically conductive, flexible multifunctional nanostructured composites with lower T\({}_{\text{g}}\) compared to PLA, finding applications as shape-memory polymers [14; 15]. In the present work, we report the melt extrusion of PLA with multiwall CNT (MWCNT), comparing composites with the neat polymer and PPG as a plasticizer. The influence of PPG on the dispersion of MWCNT in PLA and its plasticizing effect is studied. Electrical conductivity and sensing ability under acetone vapor are studied for composites with different MWCNT content. Filaments were produced with different diameters foreseeing an application in textile wearable devices.