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摘要
A new monomer 2-beta-pinenyloxy-5-vinylbenzaldehyde (POVB) containing both formyl and beta-Pinene functional groups, was designed and prepared readily by the reaction of beta-pinenyl-4-methylbenzensulfonate with 2-hydroxy-5-vinylbenzaldehyde, and its structure was confirmed via elemental analysis, MS and NMR spectroscopy. The conventional radical polymerization of the new monomer POVB was investigated with AIBN in THF at 60 degrees C, and the polymer with high molecular weight (M(n) = 132100, M(w)/M(n) = 2. 20, measured by GPC) was obtained at 68% conversion in 24 h, indicating the new monomer exhibited good polymerization activity. The thermal properties of the polymer were studied using TGA and DSC. The polymer exhibited good thermal stability until 320 degrees C, and had a relatively high glass transition temperature (T(g)) at 130.6 degrees C due to its bulky substituents. Furthermore, the "living"/controlled radical polymerization of POVB was successfully achieved using 2,2'-azobis(isobutyronitrile) as the initiator and 1-phenylethyl phenyldithioacetate (PEPDA) as the reversible addition-fragmentation chain transfer (RAFT) agent at 60 degrees C in tetrahydrofuran. Compared with 1-phenylethyl dithiobenzoate (PEDB), a much smaller retardation was observed using PEPDA as a RAFT agent. The polymerization followed first-order kinetics, the number-average molecular weight of the obtained polymers increased in direct proportion to the monomer conversion, and the molecular weight distribution was narrow (polydispersity index < 1. 2). The chain and terminal structures of the obtained poly(POVB) were confirmed with the (1)H-NMR analysis. Moreover, the circular dichroism ( CD) spectra of the resulting polymers in THF solutions confirmed that poly(POVB) s were optically active.
- 出版日期2010-8-20
- 单位仲恺农业工程学院
