POS1-0799
Topology-Dependent Swelling and Mechanics of PNIPAM Hydrogels
When and Where
Nov 30, -0001
12:00am - 12:00am
Presenter(s)
Suraj Aswale (Department of Polymer Science and Engineering, Pusan National University, Busan.)
Co-Author(s)
Abstract
Polymer topology has emerged as an effective strategy for tuning hydrogel properties beyond conventional chemical modifications. This work investigates the influence of linear and cyclic poly(acrylic acid) (PAA) on the swelling and mechanical behavior of poly(N-isopropylacrylamide) (PNIPAM)-based semi-interpenetrating polymer network hydrogels. Linear and cyclic PAA samples with comparable molecular weights were incorporated into PNIPAM networks to isolate the effect of chain topology. Swelling studies demonstrated that hydrogels containing cyclic PAA exhibited lower and more controlled swelling across different pH conditions than those containing linear PAA. The restricted chain mobility associated with the cyclic architecture is believed to limit network expansion and improve dimensional stability. Rheological measurements revealed that the incorporation of PAA altered the mechanical response of PNIPAM hydrogels in a topology-dependent manner. In the swollen state, cyclic PAA-containing hydrogels showed enhanced network stability, consistent with an additional topological constraint effect. However, during thermally induced deswelling, hydrogels containing linear PAA exhibited the greatest mechanical strength. These results demonstrate that polymer topology significantly influences the responsive behavior of PNIPAM hydrogels. Understanding the distinct roles of linear and cyclic polymers provides new opportunities for designing advanced stimuli-responsive hydrogels with tailored swelling and mechanical properties.
