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Abstract Carbon‐based nanoparticles are widely regarded as promising nanofillers in nanocomposites to pursue advanced properties. To date, there has been a lack of systematic investigation into the structural variations of nanofillers and their influences on dispersion characteristics, as well as the resulting mechanical properties of nanocomposites. In this study, nanodiamond (ND), carbon nanotube (CNT), and graphene (GNP) were selected as the representative zero‐, one‐, and two‐dimensional nanofillers, respectively. A novel functionalization technique utilizing carboxymethyl cellulose (CMC) was employed to disperse nanofillers. The various characterization techniques and experimental results revealed that CMC functionalization was effective in reducing the agglomeration and improving the distribution uniformity of all three nanofillers. Among the three nanofillers, zero‐dimensional ND exhibited the most homogeneous dispersion quality in epoxy nanocomposites. The strongest abrasion resistance was found in ND‐reinforced epoxy nanocomposites, while CNT‐reinforced epoxy nanocomposites exhibited the best tensile properties. HighlightsNanodiamond with a spherical structure had better dispersion characteristics.Cylindrical carbon nanotube and planar graphene tended to agglomerate.Nanodiamond reinforced nanocomposites had better abrasion resistance.Carbon nanotube reinforced nanocomposites had better tensile properties.Carboxymethyl cellulose functionalization was valid for all three nanofillers.
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This content will become publicly available on July 10, 2026
Direct ink writing of piezoresistive isoprene rubber nanocomposites
Abstract Despite the growing interest in flexible electronics and wearable sensors, research in piezoresistive polymer nanocomposites has stagnated in consideration of the polymer matrices, particularly in additive manufacturing (AM) applications. This research focuses on using a low‐molecular isoprene rubber (IR) as a matrix filled with carbonaceous nanoparticles conductive carbon black (CCB) and carbon nanotubes (CNT) to create piezoresistive sensors printed via direct ink writing (DIW). Using IR as a matrix not only provides an avenue for an alternate sensor matrix, but also offers a distinct advantage for retrofit sensor applications to other diene rubber substrates due to both the feedstock and substrate possessing the same vulcanization mechanism. Thereby, the rheological, mechanical, and piezoresistive properties of the IR nanocomposites are fully investigated, with emphasis on non‐ambient conditions (temperature and durability). In this work it is shown that while CCB exhibits a lower gauge factor (between 1.5 and 8) across all strain rates, strain ranges, and temperatures when compared to CNT compounds (gauge factors between 1.5 and 260), CCB compounds possess better linearity, less temperature deviation, and overall better performance under cyclic loading conditions. This is followed by demonstrations for real‐world applications, including the direct‐to‐product printing of a CCB strain gauge on a chloroprene rubber substrate. HighlightsAM via DIW of piezoresistive isoprene sensors filled with conductive CB and multi‐wall carbon nanotubes.Printed samples capable of achieving tensile strength >3.5 MPa.CB sensors showed less sensitivity, but better durability and repeatability compared to carbon nanotube filled sensors.Piezoresistive isoprene strain gauge printed on chloroprene substrate with direct adhesion.
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- Award ID(s):
- 2347700
- PAR ID:
- 10632290
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Polymer Composites
- Volume:
- 46
- Issue:
- 10
- ISSN:
- 0272-8397
- Page Range / eLocation ID:
- 8988 to 9006
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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