ABSTRACT
Hydrogels are three-dimensional (3D) polymeric networks that can confine a substantial fraction of water within their structure. Photopolymerization is one of the efficient methods to prepare hydrogels, by which polymers undergo a photocrosslinking process upon light exposure for a few minutes in the presence of an initiator. In comparison to other crosslinking methods (e.g. physical crosslinking and chemical addition/condensation crosslinking), photopolymerization has many advantages including fast and effective polymerization and good spatio-temporal control of hydrogel formation, and can occur under ambient reaction conditions at room temperature in physiological solutions. For these reasons, photocurable hydrogels have been extensively utilized for biomedical applications such as 3D hydrogel scaffold fabrication, drug delivery systems, and 3D bio-printing.
This chapter begins with the introduction of photoinitiators, which play an important role in the preparation of photocurable hydrogels. Subsequently, two types of photocurable hydrogels and their preparation methods are described; the first section focuses on photocurable hydrogels made from synthetic materials, followed by the second section on those from natural materials.
