Copolymerization and terpolymerization of carbon dioxide/propylene oxide/phthalic anhydride using a (salen)Co(III) complex tethering four quaternary ammonium salts

Beilstein Journal of Organic Chemistry

Jong Yeob Jeon¹  Seong Chan Eo¹  Bun Yeoul Lee¹  Jobi Kodiyan Varghese¹ 

[1] Department of Molecular Science and Technology, Ajou University, Suwon 443-749 Korea;

关键词: carbon dioxide;    CO2 chemistry;    cobalt complex;    phthalic anhydride;    propylene oxide;    terpolymerization;   

DOI  :  10.3762/bjoc.10.187

来源: DOAJ

【 摘 要 】

The (salen)Co(III) complex 1 tethering four quaternary ammonium salts, which is a highly active catalyst in CO2/epoxide copolymerizations, shows high activity for propylene oxide/phthalic anhydride (PO/PA) copolymerizations and PO/CO2/PA terpolymerizations. In the PO/PA copolymerizations, full conversion of PA was achieved within 5 h, and strictly alternating copolymers of poly(1,2-propylene phthalate)s were afforded without any formation of ether linkages. In the PO/CO2/PA terpolymerizations, full conversion of PA was also achieved within 4 h. The resulting polymers were gradient poly(1,2-propylene carbonate-co-phthalate)s because of the drift in the PA concentration during the terpolymerization. Both polymerizations showed immortal polymerization character; therefore, the molecular weights were determined by the activity (g/mol-1) and the number of chain-growing sites per 1 [anions in 1 (5) + water (present as impurity) + ethanol (deliberately fed)], and the molecular weight distributions were narrow (Mw/Mn, 1.05–1.5). Because of the extremely high activity of 1, high-molecular-weight polymers were generated (Mn up to 170,000 and 350,000 for the PO/PA copolymerization and PO/CO2/PA terpolymerization, respectively). The terpolymers bearing a substantial number of PA units (fPA, 0.23) showed a higher glass-transition temperature (48 °C) than the CO2/PO alternating copolymer (40 °C).

【 授权许可】

Unknown