Study On Synthesis Of End-functionalized And Pendant-functionalized Fluorescent Polymers Containing Benzoxazole Group By Atom Transfer Radical Polymerization

(1) Functionalized polystyrene (PSt) and PMMA was synthesized utilizing atom transfer radical polymerization (ATRP), which was conducted by using 2-(4-chloromethyl- phenyl)-benzoxazole (CMPB) as initiator, CuCl/PMDETA as catalyst, and cyclohexanone as solvent. The mechanism of ATRP was proved by characterizing the structure of polymers by 1H NMR. The polymerization showed first order with respect to monomer concentration and relatively narrow polydispersity (Mw/Mn range from 1.30 to 1.50). Factors such as different reaction temperatures, mole ratio of monomer to initiator and so on, which can affect the ATRP system, were discussed in the paper. Moreover, CMPB showed high activity and could initiate styrene and MMA polymerization even at ambient temperature. The optical property of the initiator was well preserved in the resulting polymers, and the end-functionalized polymers exhibited strong fluorescent emission at 360nm.(2) Methacrylic acid 4-(2-benzoxazol)-benzyl ester (MABE), a novel monomer bearing the benzoxazole moiety as the side group, was polymerized via atom transfer radical polymerization (ATRP) using ethyl 2-bromoisobutyrate (EBIB) as initiator and CuBr as a catalyst complexed with N,N,N',N",N"-pentamethyldiethylenetriamine (PMDETA) as ligand. The mechanism of ATRP was proved by characterizing the structure of poly(MABE) by 1H NMR. The polymerization showed first order with respect to monomer concentration and relatively narrow polydispersity (Mw/Mn range from 1.40 to 1.50). Factors such as different reaction temperatures, mole ratio of monomer to initiator, which can affect the ATRP system, were discussed in the paper. MABE has high activity and can be polymerized even at ambient temperature.