Supramolecularly Designed Thermoresponsive Polymers in Different Polymer Backbones. Issue 5 (29th January 2020)

• Record Type: Journal Article
• Authors: Naya, Masami; Kokado, Kenta; Landenberger, Kira Beth; Kanaoka, Shokyoku; Aoshima, Sadahito; Sada, Kazuki
• Is Part Of: Macromolecular chemistry and physics. Volume 221:Issue 5(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-01-29
• Subjects: lower critical solution temperature (LCST) -- polymer backbones -- supramolecular chemistry -- thermoresponsive polymers; Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201900455
• Languages: English
• ISSNs: 1022-1352

Abstract

Abstract: Thermoresponsive polymers in water, for example, poly( N ‐isopropylacrylamide) (PNIPAM) are investigated extensively, due to a wide range of biomedical applications. However, the attempts to control thermoresponsiveness are still rare in less or nonpolar media. Herein, the three thermoresponsive homopolymers tethering an N ‐butylurea group in the side chain with a different polymer backbone are reported. They exhibit lower critical solution temperature (LCST)‐type and upper critical solution temperature (UCST)‐type thermoresponsiveness depending on association of the urea group in the polymer chain and hydrogen bonding small molecules (effectors) in ternary systems (polymer/effector/organic solvent). The difference of polymer backbone appears as their change of solvophobicity in organic solvents. Poly(methacrylate) backbone needs more amount of the effector in nonpolar organic solvents, and poly(vinyl ether) backbone needs more amount in polar organic solvents. However, the influence of polymer backbone is too little to change the phase transition behavior, and the thermoresponsiveness is dominated by association and dissociation of hydrogen bondings between polymers and effectors. The supramolecular design of the thermoresponsive polymers is strong and extensible for the design of their phase transitions. Abstract : Thermoresponsive polymers tethering urea groups and different polymer backbones are prepared. They exhibit the lower critical solution temperature‐type thermoresponsiveness depending on supramolecular interaction in ternary systems. The different polymer backbone causes modest change of solvophobicity in organic solvents, and their phase transitions are dominated by association and dissociation of hydrogen bonds of polymers.