Dr. Ildoo Chung, Professor, Department of Polymer Science and Engineering, Pusan National University, Busan 46241, Korea

Biography: Professor Ildoo Chung joined the faculty of Department of Polymer Science and Engineering at Pusan National University, Korea in 2005. Prior to that, he completed his postdoctoral training with Professor Jimmy Mays in Department of Chemistry at University of Tennessee, and with Professor Dong Xie in Department of Biomedical Engineering at University of Alabama at Birmingham, USA. He received his Ph. D. at Pusan National University in 2000. He is now serving editor-in-chief of Journal of Adhesion and Interface, and member of board of directors in the Polymer Society of Korea, the Korea Society of Adhesion and Interface, Korea Polyurethane Society, and Asian Cyclodextrin Conference. He had over 70 peer-reviewed publications and over 150 presentations in national and international conferences. His research interests are focused on polymer synthesis such as atom transfer radical polymerization (ATRP), radical addition-fragmentation transfer (RAFT) polymerization and advanced polymeric biomaterials such as drug delivery system, hard/soft tissue compatible polymers, photocurable 3D printing polymer, biodegradable polymer and composite system.

Speech Title: Biodegradable Nanoporous Microspheres by RAFT and UV Irradiation
Abstract: Nanoporous microspheres based on polycaprolactone (PCL), polylactide (PLA) and photodegradable poly(methyl vinyl ketone) (PMVK) were synthesized and characterized. In this study, biodegradable triblock copolymers were first synthesized by ring opening polymerization of lactide followed by RAFT polymerization of methyl vinyl ketone (MVK), and then used to fabricate microsphere by emulsion method. In order to polymerize by RAFT method, macro-CTA (chain transfer agent) was synthesized by reacting carboxylic acid-terminated CTA, S-1-dodecyl-S’-(α,α’-dimethyl-α’’-acetic acid) trithiocarbonate (DDMAT) with hydroxyl terminated PLA-PCL-PLA triblock copolymer, and then used for the synthesis of block copolymer with methyl vinyl ketone (MVK). The synthesized block copolymers were characterized by FT-IR, 1H NMR spectroscopies. Gel permeation chromatography (GPC) was used to evaluate molecular weight and molecular weight distribution and monitor photodegradabilities of block copolymers. The morphology of microparticles before and after UV irradiation confirmed by SEM and TEM images showed that spherical microspheres before UV irradiation were changed to disk-shaped microparticles, owing to collapsing of PMVK moieties by UV irradiation.
Keywords: Biodegradable; Nanoporous; Microsphere; RAFT; UV irradiation