Ring-opening Polymerization Of P-dioxanone By Microwave Irradiation

Microwave heating, which presents a totally different heating mode from conventional heating, has been proved to be more rapid and efficient, and is a green method for chemical synthesis because of its high efficiency and heating homogeneity. It offers a clean, cheap, and convenient method for heating. Some polymerization reactions are also significantly improved by microwave energy, and the microwave-assisted preparations of biodegradable polymers have been studied. More recently,there has been growing interest in the microwave synthesis of macromolecules.As a novel biodegradable polymer, poly (p-dioxanone)(PPDO) has its own special characters. Except for its ultimate biodegradability due to the existence of ester bonds in polymer chains, the unique ether bonds also endue it with good flexibility. It has been used in medical, such as bone or tissue fixation device and drug delivery system. However it has not been widely used now because of its high cost and some defects. Generally, it takes more than 10h and even several days to complete the ring-opening polymerization by conventional heating.In order to reduce the reaction time, PPDO was synthesized using stannous octoate as catalyst under microwave irradiation. PPDO samples with an intrinsic viscosity of 1.18dL/g could be synthesized within 10min when the microwave power was 270 W.The heating characteristics of PDO under microwave irradiation were...