摘要
A betaine-type styrene monomer with the quaternary ammonium-borate anion inner-salt pair was synthesized through the quatemization reaction and polymerized to afford the target polybetaine of poly（4-vinylbenzyl methyl-diethanol ammonium borate） （PVMAB）. The chemical structures of the monomer and polymer were well demonstrated with 1H-NMR and llB-NMR spectra analysis. The thermal-sensitive experiment showed that PVMAB in water afforded gradually well- defined sigmoidal transmittance-temperature （T-t） curves along with the increasing polymer concentration. However, the phase transition temperatures at the bottom of the S-shaped curves were always below l0 ~C due to the very weak zwitterionic association of the ammonium-borate inner-salt pairs. The UCST phase transition could also be tuned by changing the ethanol content in the ethanol/water mixture. And the cytotoxicity experiment demonstrated the good biomimetic property of PVMAB. This study enriches the toolbox of polybetaines by introducing the quaternary ammonium- borate anion zwitterionic pair in the repeat units, therefore broadens the scope of synthetic polybetaines.
A betaine-type styrene monomer with the quaternary ammonium-borate anion inner-salt pair was synthesized through the quatemization reaction and polymerized to afford the target polybetaine of poly（4-vinylbenzyl methyl-diethanol ammonium borate） （PVMAB）. The chemical structures of the monomer and polymer were well demonstrated with 1H-NMR and llB-NMR spectra analysis. The thermal-sensitive experiment showed that PVMAB in water afforded gradually well- defined sigmoidal transmittance-temperature （T-t） curves along with the increasing polymer concentration. However, the phase transition temperatures at the bottom of the S-shaped curves were always below l0 ~C due to the very weak zwitterionic association of the ammonium-borate inner-salt pairs. The UCST phase transition could also be tuned by changing the ethanol content in the ethanol/water mixture. And the cytotoxicity experiment demonstrated the good biomimetic property of PVMAB. This study enriches the toolbox of polybetaines by introducing the quaternary ammonium- borate anion zwitterionic pair in the repeat units, therefore broadens the scope of synthetic polybetaines.
基金
financially supported by the National Natural Science Foundation of China(No.21374056)
the Program for Changjiang Scholars and Innovative Research Team in Universities(IRT 14R33)
the Natural Science Basic Research Plan in Shaanxi Province of China(NSBRP-SPC 2014JM2051)
the Program of Introducing Talents of Discipline to Universities(B14041)
Shaanxi Innovative Research Team for Key Science and Technology(2012KCT-21,2013KCT-17)
the One Hundred Plan of Shaanxi Province
