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Abstract Boron nitride nanotubes (BNNT) uniformly dispersed in stretchable materials, such as poly(dimethylsiloxane) (PDMS), could create the next generation of composites with augmented mechanical, thermal, and piezoelectric characteristics. This work reports tunable piezoelectricity of multifunctional BNNT/PDMS stretchable composites prepared via co‐solvent blending with tetrahydrofuran (THF) to disperse BNNTs in PDMS while avoiding sonication or functionalization. The resultant stretchable BNNT/PDMS composites demonstrate augmented Young's modulus (200% increase at 9 wt% BNNT) and thermal conductivity (120% increase at 9 wt% BNNT) without losing stretchability. Furthermore, BNNT/PDMS composites demonstrate piezoelectric responses that are linearly proportional to BNNT wt%, achieving a piezoelectric constant (|d33|) of 18 pmV−1at 9 wt% BNNT without poling, which is competitive with commercial piezoelectric polymers. Uniquely, BNNT/PDMS accommodates tensile strains up to 60% without plastic deformation by aligning BNNTs, which enhances the composites’ piezoelectric response approximately five times. Finally, the combined stretchable and piezoelectric nature of the composite was exploited to produce a vibration sensor sensitive to low‐frequency (≈1 kHz) excitation. This is the first demonstration of multifunctional, stretchable BNNT/PDMS composites with enhanced mechanical strength and thermal conductivity and furthermore tunable piezoelectric response by varying BNNT wt% and applied strain, permitting applications in soft actuators and vibration sensors.
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Development of A Biodegradable Tapioca Starch‐Based Polymeric Composite for Non‐Structural Applications
ABSTRACT This study presents a novel, bio‐based polymer composite derived from tapioca starch and reinforced with jute fibers, designed for non‐load bearing structural applications. The developed composite demonstrated significant thermal stability, with a single decomposition reaction observed above 300°C via TGA, surpassing many synthetic polymers. DSC analysis revealed a glass transition temperature (Tg) of 69.55°C and notable thermal energy storage capability. Mechanical characterization, including three‐point bending, tensile, and compressive tests, confirmed effective fiber wetting and a tensile strength of 9 MPa for the composite. Furthermore, the composite exhibited mild electrical conductivity of 3.62 × 10−7 S/m. Structural characterizations (SEM, XRD, FTIR) revealed the presence of an N‐H bond, a functional group common in conductive polymers, suggesting its potential as a mild conductor. Density functional theory simulations provided further insights into the biopolymer's molecular structure. This research highlights the promising potential of tapioca starch composites for various engineering applications, particularly as sustainable packaging materials.
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- Award ID(s):
- 2418415
- PAR ID:
- 10643825
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- SPE Polymers
- Volume:
- 6
- Issue:
- 4
- ISSN:
- 2690-3857
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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