On June 9, 2020, Bear learned that Shanghai University of Applied Technology has 3D printed a tough and conductive polymer hydrogel (CPH) to produce a flexible wearable motion sensor.
The mechanical and electrical properties of the sensor were tested and evaluated.
The team found that CPH in the study could provide excellent 3D printing materials for many applications, including soft robots and even wound dressings.

Conductive hydrogel
Hydrogels have been widely used in research projects such as regenerative medicine, soft robotics and 4D printing.
Unfortunately, the mechanical strength of conventional hydrogels is usually low, limiting their potential for low-stress applications.
However, with the latest advances in materials science, highly tensile hydrogels, conductive hydrogels, 3D-printed hydrogels and self-healing hydrogels have been formulated.
Conductive hydrogels, in particular, are of great interest because of their strong adhesion, high porosity, sensitive expansibility and biocompatibility.
They convert physical stimuli into electrical signals that can be recorded.
Given the many attractive features, researchers saw some potential innovative applications for conductive hydrogels and set out to 3D print their own flexible wearable motion sensors.
A 3D printed flexible motion sensor
The team used a DLP 3D printer, which 3D printed the PHEa-PSS /PEDOT hydrogel motion sensor.
The newly prepared hydrogel was tested and found to exhibit some surprisingly ideal mechanical and electrical properties.
Under the condition of 12% EDOT content, the tensile strength of hydrogel was close to 8MPa, while the conductivity sat at 1.2S/cm, and the elasticity remained unchanged.

Further functional testing of the sensor by human fingers revealed that it could accurately convert physical pressure changes into sensitive electrical signals.
The team subjected the sensor to a wide range of forces and deformations without tearing or plastic deformation, confirming its toughness and flexibility.
Experimental hydrogels can be used to effectively 3D print pressure sensors that can monitor human activity.
The team hopes to eventually apply the technology to stretchable electrical equipment and soft robots.

More research details can be titled ‘Tough and conductive polymer hydrogel -based on double network for photo curing found in 3 d printing papers’.
The paper was written by Xueyuan Ding, Runping Jia, Zuzhong Gan, Yong Du, Dayang Wang, and Xiaowei Xu.
Compiled from 3Dprintingindustry