Synthesis and Characterization of Vinyl Acetate and N-Isopropylacrylamide Copolymers via Microwave-Assisted RAFT Polymerization

• Main Authors: Nien-Chu Ting, 丁念主
• Other Authors: Mong Liang
• Format: Others
• Language: zh-TW
• Online Access: http://ndltd.ncl.edu.tw/handle/95597690538369791693

碩士 === 國立嘉義大學 === 應用化學系研究所 === 100 === Poly(Vinyl Acetate) (PVAc) was polymerized under microwave irradiation and used as a macro-RAFT reagent to synthesize the PVAc-b-PNIPAm. PVAc is a precursor of Poly(Vinyl Alcohol) (PVA), which undergoes hydrolyzation to afford the PVA-b-PNIPAm. The phase transition was reversible and can be measured by its lower critical solution temperature (LCST). By NMR, FT-IR and transmission electron microscopy (TEM) we can identify the structure and composition of copolymers. The molecular weight of polymer can be traced by GPC, PVAc with PDI of 1.15~1.29 was prepared in less than 7.5 min. The activation energy of PVAc is about 98.5(kJ/mol). It is found that the micelle structure of PVA53-b-PNIPAm186 at 50℃ have a diameter ranging from 50~100nm. The LCST of copolymers could be designed greater than physiologic body temperature (Tb~37℃), but less than the temperature in a region fo local hyperthermia (Th~42℃), which could be useful in drug delievery applications.