The extracellular matrix (ECM) has force‐responsive (i.e., mechanochemical) properties that enable adaptation to mechanical loading through changes in fibrous network structure and interfiber bonding. Imparting such properties into synthetic fibrous materials will allow reinforcement under mechanical load, the potential for material self‐adhesion, and the general mimicking of ECM. Multifiber hydrogel networks are developed through the electrospinning of multiple fibrous hydrogel populations, where fibers contain complementary chemical moieties (e.g., aldehyde and hydrazide groups) that form covalent bonds within minutes when brought into contact under mechanical load. These fiber interactions lead to microscale anisotropy, as well as increased material stiffness and plastic deformation. Macroscale structures (e.g., tubes and layered scaffolds) are fabricated from these materials through interfiber bonding and adhesion when placed into contact while maintaining a microscale fibrous architecture. The design principles for engineering plasticity described can be applied to numerous material systems to introduce unique properties, from textiles to biomedical applications.
Conventional strain gauges are not designed for accurate measurement over the large range of deformations possible in compliant textiles. The thin, lightweight, and flexible nature of textiles also makes it challenging to attach strain gauges in a way that does not affect the mechanical properties. In this manuscript, soft, highly extensible fibers that propagate light (i.e., stretchable lightguides) are stitched as a strain gauge to map the deformation of a nylon parachute textile under tension. When under load, these fiber optic strain gauges propagate less light, and this strain‐induced light modulation is used to accurately (absolute error≈2.93%; Std. Dev.: 3.02%) measure strain in the <30% range before these textiles fail. This system has directionality; strain in parallel to the sensor results in little light attenuation while perpendicular loading shows high sensitivity (Gauge factor⊥≈24.8 and Gauge factor||≈0.05 at the first 1% strain). Structural and optical simulations are coupled to demonstrate that load transfer on the fiber optic by the stitchwork is the dominating cause of signal modulation. To further validate the hypotheses, digital image correlation was used under dynamic loading conditions to show that these sensors do not significantly affect the mechanical properties.
more » « less- PAR ID:
- 10374880
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Materials Technologies
- Volume:
- 7
- Issue:
- 12
- ISSN:
- 2365-709X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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