Tunable, concentration‐independent, sharp, hysteresis‐free UCST phase transition from poly(N‐acryloyl glycinamide‐acrylonitrile) system. Issue 2 (5th October 2016)

• Record Type: Journal Article
• Authors: Käfer, Florian; Lerch, Arne; Agarwal, Seema
• Is Part Of: Journal of polymer science. Volume 55:Issue 2(2017)
• Page Start: 274
• Page End: 279
• Publication Date: 2016-10-05
• Subjects: N‐acryloyl glycinamide‐acrylonitrile -- micelle formation -- RAFT polymerization -- thermoresponsive polymers -- UCST; 547
• DOI: 10.1002/pola.28374
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: Poly( N ‐acryloylglycinamide‐co‐acrylonitrile) (poly(NAGA‐AN)) copolymers were synthesized using reversible‐addition‐fragmentation transfer polymerization. In contrast to poly(NAGA) the thermoresponsive behavior of poly(NAGA‐AN) shows a narrow cooling/heating hysteresis in water with a tunable cloud point, depending on the acrylonitrile amount in polymer. Furthermore, we showed that there is no significant effect of the solution concentration on the cloud point and stable phase transition behavior in electrolyte solutions, which is presumable controlled by forming stable micellar like structures as a result of the block/graft‐copolymer structure. This is in contrast to poly(NAGA) which shows a strong concentration dependent cloud point in aqueous solution with a broad cooling/heating hysteresis. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2017, 55, 274–279 Abstract : Thermoresponsive polymer of upper critical solution temperature‐type exhibiting a combination of properties, such as cloud point tunability, very sharp phase transitions in water and electrolyte, almost no hysteresis, and cloud points independent of concentration in a very broad range, is achieved by RAFT polymerization of N ‐acryloyl glycinamide and acrylonitrile.