Flexible, Degradable, and Cost-Effective Strain Sensor Fabricated by a Scalable Papermaking Procedure

Abstract

Flexible strain sensors (FSSs) are essential components in intelligent systems, especially in soft robots, human sport monitoring, ect., but their scalable preparation remains a challenge. In this work, we first proposed and demonstrated a strategy to prepare FSS with a scalable and cost-effective papermaking procedure. Cellulose fibers from waste papers and conductive graphite were mixed and subject to a paper former (papermaking machine in laboratory), producing a strain sensitive paper with diameter of 20 cm in 10 min. With the scrips from the strain sensitive paper, the strain sensor was assembled showing good sensing performance for both bending (gauge factor (GF) = 27, response time of 360 ms) and twisting (GF = 26.5, response time of 440 ms) strains. It can be used in movement detections of soft matters (such as a plastic ruler), elbow joints of a puppet, and human fingers. The cost of the sensor was calculated as low as $0.00013, and the strain sensitive paper can be degraded in around 1 min in water under stirring. Furthermore, the strategy can be expanded to the sensor based on carbon black (CB), indicating a universality, which may pave a way for developing more intelligent materials and devices.

Paper-based flexible strain and pressure sensor with enhanced mechanical strength and super-hydrophobicity that can work under water

“…The reported strategies include pencil scribing, printing, or dip-coating of conductive matter on filter paper, [26][27][28][29] which may be limited by the commercially available paper substrates. Recently, our group 30 developed a flexible strain sensor using a papermaking technique, which was a scalable strategy using cellulose fibers from waste paper as raw materials, thus keeping costs quite low. Furthermore, different functional materials can be easily introduced into the composite paper during the papermaking protocol to endow the flexible sensors with new features.…”

Design of a Waste Paper‐Derived Chemically ‘Reactive’ and Durable Functional Material with Tailorable Mechanical Property Following an Ambient and Sustainable Chemical Approach

“…The presence of ‘reactive’ acrylate groups in the waste paper sponge rendered it highly reactive at ambient conditions towards some specific nucleophiles (Figure 2B). The post covalent modification (Figure 2C) of the chemically ‘reactive’ waste paper sponge with amine containing small molecule, octadecylamine (ODA) transformed the hydrophilic sponge into a superhydrophobic sponge with water contact angle (WCA) ∼160° as shown in Figure 2D, E. The successful modification of residual acrylate groups in the amine functionalized waste paper derived sponge was further confirmed through standard FTIR analysis [43,44] . The appearance of the peak at 1408 cm −1 and 1730 cm −1 corresponding to the C−H stretching of β carbon of the vinyl group and the carbonyl stretching respectively confirmed the presence of the multifunctional acrylate cross‐linker, i. e. 5Acl.…”

A Graphical Pressure Sensor Array with Multilayered Structure Based on Graphene and Paper Substrate

“…[ 27 ] researched a graphene–paper pressure sensor using a laminated structure, which can be used for pulse detection, respiratory detection, and voice recognition. In addition, paper‐based flexible devices can also be prepared by mixing paper with nanomaterials during the paper‐making process [ 28–30 ] or high‐temperature pyrolysis. [ 31 ] However, easy processing methods for preparing all‐paper‐based pressure sensors with high sensitivity need to be studied.…”