（Macromol. Mater. Eng.）A Thermo- and Moisture-Responsive Zwitterionic Shape Memory Polymer for Novel Self-Healable Wound Dressing Applications
writer：Guo Li,* Youpeng Wang, Shuwei Wang, and Jinqiang Jiang*
keywords：composite hydrogel, controlled release, hydrophobic drug, poly(vinyl alcohol), ultrasound
source：期刊
Issue time：2018年
Developing wound dressings that have strong adhesion strength without
causing any conglutination to the wound site is still challenging. Herein,
is proposed that zwitterionic shape memory polymers can be applied as
promising candidates for wound dressing. Sulfobetaine methacrylate (SBMA)
is copolymerized with 2,3-dihydroxypropyl methacrylate (DHMA) in the presence
of boric acid as a cross-linking agent. The prepared material exhibits
multi-stimuli responsive shape memory behaviors: it can rapidly return to its
initial shape upon heating to 90 °C, and a gradual recovery is also observed
by absorbing moisture in humid environments. The shape memory effect can
be well adjusted via incorporation of sodium chloride to induce the dissociation
of electrostatic interactions between PSBMA chains, leading to reduced
transition temperature and faster shape recovery rate. Moreover, the dynamic
nature of boron ester bonds and electrostatic interaction endows the material
with effective and rapid self-healing ability. It is also demonstrated that the
deployment process of the dressing that a sample with an initially circular
shape can perfectly fit and tightly bind to the wound site after moistureinduced
shape recovery. The proposed zwitterionic polymer can possibly
extend the application scope of shape memory polymers and pave a new way
for the design of wound dressings.