CJCU

Chem. J. Chinese Universities ›› 2006, Vol. 27 ›› Issue (5): 956.doi:

Previous Articles     Next Articles

Synthesis and Self-assembly of Temperature- and pH-Sensitive Diblock Copolymer of Poly(acrylic acid)-b-poly(N-isopropylacrylamide)

LI Gui-Ying, AN Ying-Li, HE Zhe-|Ping, MA Ru-Jiang, ZHANG Wang-Qing, SHI Lin-Qi*   

  1. Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, Nankai University, Tianjin 300071, China
  • Received:1900-01-01 Revised:1900-01-01 Online:2006-05-10 Published:2006-05-10
  • Contact: SHI Lin-Qi

PDF (PC)

Cited

12

Abstract:

Diblock copolymer of poly(t-butyl acrylate)-b-poly(N-isopropylacrylamide)(PtBA-b-PNIPAM) with designed molecular weight and narrow molecular weight distributions was synthesized by sequential atom transfer radical polymerization(ATRP) of butyl acrylate and N-isopropylacrylamide using CuCl/(1,1,4,7,7-pentamethyl diethylenetriamine(PMEDTA) and CuCl/tris(2-dimethylaminoethyl)amine(Me6TREN) as the catalyst respectively in a mixture solvent of butanone and 2-propanol. Temperature- and pH-sensitive block copolymer of poly(acrylic acid)-b-poly(N-isopropylacrylamide)(PAA-b-PNIPAM) was realized after hydrolysis of PtBA-b-PNIPAM in toluene. PAA-b-PNIPAM existed as single molecules in aqueous solution at 25 ℃ and pH>pKa of PAA. Increasing temperature above LCST of PNIPAM or decreasing pH value lower pKa of PAA respectively formed PNIPAM-core micelles or PAA-core micelles.

Key words: PAA-b-PNIPAM; Atom transfer radical polymerization(ATRP); Self-assembly; Environmental-sensitivity

CLC Number: 

TrendMD: