Water Induced Shape Memory and Healing Effects by Introducing Carboxymethyl Cellulose Sodium into Poly(vinyl alcohol)

Water as a common, easily obtained, and environmentally friendly stimulus has been explored in stimuli-responsive materials. In this paper, a series of composites, named as PVA(n)-CMC(m)-GA, were prepared by filling the carboxymethyl cellulose sodium (CMC) into chemical cross-linked poly(vinyl alcohol) (PVA). These composites demonstrated both water induced shape memory and self-healing effect. CMC with water sensitivity help the composite absorbing water to decrease the Tg of composite to cause shape recovery. And CMC with water solubility is also a good healing agent, which can freely move across the cutting cross-section in wet condition and form hydrogen bonds with PVA chains in dry condition to achieve healing. Water can affect the hydrogen bonding interactions between CMC and PVA, and which play a key role in the water-stimuli responsive properties. This study provides a relatively simple and low cost way to obtain water-induced multifunction materials.