CHAPTER 3: Thiol‐X Chemistries for the Production of Degradable Polymers

This Chapter reviews the use of thiol‐X chemistries in the synthesis of degradable polymers. In particular, thiol‐ene and thiol‐Michael chemistries have been widely used because of their ability to be high yielding, orthogonal and functional group tolerant. They also exhibit the capacity to be conducted in physiological conditions, thus allowing them to be utilized in vivo. Furthermore, a wide range of thiol‐containing systems, such as cysteine residues in peptides, can be incorporated into the polymer material, thereby providing functionality that may be specifically tailored, e.g. for targeted delivery, degradation, adhesion or cell growth. Degradation of such polymers may be achieved through a number of bond scission processes, often hydrolysis (e.g. of ester linkages) but may also be catalyzed by enzymes. Continued interest in the development of new materials for tissue engineering and the delivery of therapeutics is bound to further the involvement of thiol‐X chemistries, and should see them become mainstays in the production of biomedical devices in the near future.