Polydioxanone

Polydioxanone (PDO or PDS) or poly-p-dioxanone is a colorless, crystalline, biodegradable polymer that is used for biomedical applications, particularly in the preparation of sutures. The polymer is obtained by ring-opening polymerization of the monomer p-dioxanone, in a process requiring heat and an organometallic catalyst like zirconium acetylacetone or zinc L-lactate.



Polydioxanone is a poly (ether-ester) characterized by a glass transition temperature in the range of &minus;10 and 0 °C and a crystallinity of about 55%. Owing to the presence of an ether oxygen group into the backbone of the polymer chain, materials prepared with polydioxanone are provided with a good flexibility. It also exhibits some shape memory properties, a particular which has proved as a disadvantage in its use as suture, since polydioxanone tends to coil and retain its initial shape, making usage difficult. For the production of sutures, polydioxanone is generally extruded into fibers, however care should be taken to process the polymer to the lowest possible temperature, in order to avoid its spontaneous depolymerization back to the monomer. The sutures prepared with this material typically lose half of their mechanical strength in about three weeks and complete degradation takes place in a time frame of around six months.

Other biomedical applications for polydioxanone include its use in orthopedics, plastic surgery, drug delivery, cardiovascular applications, and tissue engineering applications.