ScholarWorks@숙명여자대학교

초록

Incorporating metallic particles in a soft polymer matrix provides a practical and cost-effective route to electrically conductive stretchable materials. Reliable performance depends critically on the microstructure established before matrix curing, which is governed by the rheology of the uncured composite paste. This study presents a solvent-assisted formulation strategy that exploits solvent-polymer compatibility to adjust viscosity during mixing and evaporation, subsequently regulating filler migration and network consolidation. Using silver (Ag) particles and multiwalled carbon nanotubes (MWCNTs) in a polydimethylsiloxane (PDMS) matrix, we show that solvent-assisted processing enhances electrical performance under strain by promoting the formation of a percolated CNT-bridging network. The composite fabricated without solvent exhibits a monotonic modulus decrease, indicating localized and poorly dispersed MWCNT aggregates. In contrast, solvent-assisted mixing produces pronounced strain stiffening, evidencing formation of a flexible, percolated MWCNT network. Among solvent-processed samples, the isopropyl alcohol (IPA)-assisted composite shows the most distinct stiffening response, suggesting a more homogeneous and extended network than that formed with chloroform. At identical Ag loading, IPA processing maintains stable electrical resistance up to similar to 80% tensile strain and reduces hysteresis during cyclic loading, whereas chloroform processing shows resistance escalation near 70% strain. These findings demonstrate that solvent-assisted processing, particularly with IPA, markedly improves filler dispersion and structural integrity in Ag/MWCNT/PDMS stretchable conductors. [GRAPHICS] .

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