Interpenetrating thermophobic and thermophilic dual responsive networks. Issue 4 (29th November 2018)

• Record Type: Journal Article
• Authors: Käfer, Florian; Hu, Yunfeng; Wang, Yan Jie; Wu, Zi Liang; Agarwal, Seema
• Is Part Of: Journal of polymer science. Volume 57:Issue 4(2019)
• Page Start: 539
• Page End: 544
• Publication Date: 2018-11-29
• Subjects: gels -- IPN -- mechanical properties -- phase transitions -- thermoresponsive; 547
• DOI: 10.1002/pola.29292
• Languages: English
• ISSNs: 0887-624X

Abstract

ABSTRACT: Poly( N ‐acryloyl glycinamide) (PNAGA)/poly( N ‐isopropyl acrylamide) (PNIPAAm) interpenetrating network (IPN) hydrogels were made by UV‐light initiated radical polymerization in two‐steps. The IPN hydrogels showed a double thermoresponsive behavior due to the combination of PNIPAAm (thermophobic) and PNAGA (thermophilic) networks. Increasing the content of the thermophobic PNIPAAm network leads to a change from a broad thermophilic volume phase transition temperature of PNAGA to a thermophilic–thermophobic‐type dual transition for the prepared IPN. Due to the double thermoresponsive character of the IPN gels, the mechanical properties are dependent upon temperature as demonstrated by performing tensile tests in water at 15 and 50 °C. Furthermore, the IPN hydrogels were characterized using turbidity measurements, SEM, and the determination of the equilibrium swelling ratio. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem.2019, 57, 539–544 Abstract : The preparation and properties of a strong double thermoresponsive interpenetrating network (IPN) consisting of PNAGA and PNIPAAm hydrogels are shown. The IPNs show mechanical as well as thermoresponsive properties dependent on the temperature and weight ratio of the two networks.