Hydrogels are highly swollen materials prepared from hydrophilic polymers that can absorb up to a thousand times their dry weight in water. As a result of their high water content, most hydrogels are soft and weak materials compared to other polymeric materials such as rubbers. For this reason, hydrogels are typically utilized for applications that do not require them to be particularly strong or resilient (for example, in foods, ointments and creams). As soft and wet materials, hydrogels are a substance that is reminiscent of soft biological tissue and have been investigated over the past 30 years as candidate materials for soft tissue engineering scaffolds.
Additive fabrication techniques such as three-dimensional (3D) and four-dimensional (4D) printing are receiving growing interest from a diverse range of fields due to their ability to quickly produce complex 3D objects. One of the exciting features of the additive fabrication process is the capacity of some systems to print multiple materials within a single component. This capability gives the operator 3D/4D control over material properties within an object by positioning and blending materials. Utilising additive fabrication, controlled variations in material properties of an object can be exploited within a device as functionality. For example, the introduction of electrically conducting materials in polymer-based objects can introduce electronic functionality. Sensing and actuating materials can provide additional utility.
However, new applications of hydrogels such as soft robotics and cartilage tissue scaffolds require hydrogels with enhanced mechanical performance, which has stimulated an investigation into how hydrogels may be made tougher and more enduring. Moreover, the parallel development of these materials and suitable 3D/4D fabrication techniques has accelerated the advancement of many technologies including soft robotics, bionic implants, sensors and controlled release systems.
The understanding of how to marry these recent advances in materials (e.g., tough, self-healing hydrogels) with manufacturing (3D/4D printing of hydrogels) for the purpose of building smart hydrogel materials is incomplete. This symposium will bring together experts from diverse and multidisciplinary research areas with a strong interest in hydrogels. Together they will contribute to the improvement in mechanical performance of hydrogel materials, and to expand the capability of additive manufacturing techniques to include actuating and electronic elements. This symposium will cover the complete range of fundamental hydrogel research to application areas such as tissue engineering, bionics and soft robotics.