Isomeric and structural effects in polymer cononsolvent systems

POLYMER

卷:170

Article

Lang, Xiaolong¹  Xu, Erin X.²  Wei, Yuan¹  Walters, Lauren N.¹  Hore, Michael J. A.¹ 

[1] Case Western Reserve Univ, Dept Macromol Sci & Engn, Cleveland, OH 44106 USA

[2] Hathaway Brown Sch, Shaker Hts, OH USA

关键词: Cononsolvency;    Thermoresponsive polymers;    PNIPAM;   

DOI  :  10.1016/j.polymer.2019.03.011

来源: Elsevier

【 摘 要 】

Thermoresponsive poly (N-isopropylacrylamide) (PNIPAM) has many analogs that exhibit cononsolvency behavior in mixtures of water and an alcohol. Cononsolvency is characterized by a combination of good solvents for a polymer that results in decreased solubility. In this work, the cononsolvency behavior of linear PNIPAM, four-arm (4f) star PNIPAM, and linear poly(N-n-propylacrylamide) (PNnPAM), with terminal groups that vary in hydrophobicity, were investigated in mixtures of water and propanol. Polymers were synthesized by RAFT polymerization and subsequently functionalized with one pot aminolysis/thiol-ene chemistry. Turbidimetry measurements and dynamic light scattering (DLS) were used to study the cononsolvency behavior by determining the critical solution temperature (T-c). The measurements show that the size and shape of the hydrophobic region of both the solvent and n-alkyl acrylamide monomer affect T-c and the phase transition behavior. The findings suggest methods to impart multiresponsiveness to soft material systems.

【 授权许可】

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