Solution-Responsive Shape-Memory Polymer Driven by Forming Hydrogen Bonding

Abstract

Recently, there is interest in triggering shape recovery of shape-memory polymers(SMPs) by novel non-external heating. In this paper, many hard works have been carried out to make SMP induced by solution. The main challenge in the development of such polymer systems is the conversion of solution-induced effects at the molecular level to macroscopic movement of working pieces. This paper presents a systematic study on the effects of solution on the glass transition temperature (Tg). The results reveal that the hydrogen bonding of shape memory polymer (SMP) was aroused by the absorbed solution that significantly reduces Tg of polymer. The mechanism behind it is solution firstly intenerates polymeric materials till the Tg of polymer lowered down to the temperature of ambient, then hydrogen bonding interaction improves the flexibility of polymeric macro-molecular chains. Thus, the shape memory effect (SME) can undergo solution-driven shape recovery. In addition, it provides a new approach that the SMP can be induced by applying non-energy stimulus. The Dynamic Mechanical Analyzer (DMA) results reveal that the modulus of polymer was softened gradually with immersion time increasing. The experimental result is approximate to the theory.

Remarkable shape memory effect of a natural biopolymer in aqueous environment

“…As shown in Figure 6, E' M A N U S C R I P T [39][40][41][42]. Moreover, the changes in the moduli of present feather rachis can be further diminished by the porous structure of medullary foam.…”

Microwave‐Induced Shape‐Memory Effect of Chemically Crosslinked Moist Poly(vinyl alcohol) Networks

“…It is observed that the T g sharply decreases with water absorption and levels off with the W value of 0.388 g Á g À1 . Water penetrates into the deformed samples and acts like a plasticizer to increase the mobility of the polymer chains, [33,48] which brings about the change in entropic elastic properties of the polymer chains. The free shape recovery of the samples is enabled even at RT (Figure 1, group A).…”

“…[27,28] Considering the extensive applications of PVA to medical devices, the promising SME of SM-PVA, and especially the unique properties of MWs, [29][30][31] we speculate that MW induced SM-PVA will have great potential for applications, in particular, in those fields that direct contact between the heating source and the heated material is not allowed and remote-controlled actuators are required, such as MW responsive sensors, vascular stents, and other medical devices. [8,32,33] Experimental Section…”

Applications of Shape Memory Polymers in Kinetic Buildings

“…Solution-responsive SMPs present a significant decrease in the modulus during phase transition [45]. Water-driven actuation of SMPs was first discussed in 2005 by Huang [46].…”