Rapid Phase Separation in Aqueous Solution of Temperature‐Sensitive Poly(N, N‐diethylacrylamide). Issue 23 (17th August 2016)

• Record Type: Journal Article
• Authors: Matsumoto, Mitsuhiro; Wakabayashi, Ryo; Tada, Takanori; Asoh, Taka‐Aki; Shoji, Tatsuya; Kitamura, Noboru; Tsuboi, Yasuyuki
• Is Part Of: Macromolecular chemistry and physics. Volume 217:Issue 23(2016:Dec.)
• Page Start: 2576
• Page End: 2583
• Publication Date: 2016-08-17
• Subjects: LCST -- phase transition -- poly(N, N‐diethylacrylamide) -- polymer aggregate -- polymer assembly; Polymers -- Periodicals; Polymerization -- Periodicals; Synthetic products -- Periodicals; Macromolecules -- Periodicals; 547.7
• DOI: 10.1002/macp.201600239
• Languages: English
• ISSNs: 1022-1352

Abstract

Abstract : The dynamic phase separation behavior in aqueous solutions of poly( N, N ‐diethylacrylamide) (PDEA), which is a representative thermoresponsive polymer, is studied using a laser temperature‐jump technique combined with transient photometry, with which the time constant for phase separation can be determined. Two components of the time constant ( τ fast and τ slow ) are clearly observed irrespective of the polymer concentration or molecular weight of the PDEA. Such a fast phase separation component ( τ fast ) has never been observed in poly( N ‐isopropylacrylamide) (PNIPAM) systems. Furthermore, the slow phase separation process of PDEA is faster than that in a PNIPAM system. It is shown that the fast phase separation process for PDEA originates from polymer aggregates formed even below the cloud point. The phase separation mechanism of PDEA is similar to that of poly (alkyl vinyl ether), rather than PNIPAM. Abstract : Poly( N, N ‐diethylacrylamide) shows slow and rapid phase separation in water. Two time constants for phase separation ( τ slow and τ fast ) are obtained using the laser temperature‐jump technique. This technique and dynamic light scattering reveal that the origin of the fast phase separation process is polymer aggregates formed even below the cloud point.