Reduced Graphene Oxide-Containing Smart Hydrogels with Excellent Electro-Response and Mechanical Properties for Soft Actuators

Abstract

A novel reduced graphene oxide/poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylamide) (rGO/poly(AMPS-co-AAm)) nanocomposite hydrogel that possesses excellent electro-response and mechanical properties has been successfully developed. The rGO nanosheets that homogeneously dispersed in the hydrogels could provide prominent conductive platforms for promoting the ion transport inside the hydrogels to generate significant osmotic pressure between the outside and inside of such nanocomposite hydrogels. Thus, the electro-responsive rate and degree of the hydrogel for both deswelling and bending performances become rapid and remarkable. Moreover, the enhanced mechanical properties including both the tensile strength and compressive strength of rGO/poly(AMPS-co-AAm) hydrogels are improved by the hydrogen-bond interactions between the rGO nanosheets and polymer chains, which could dissipate the strain energy in the polymeric networks of the hydrogels. The proposed rGO/poly(AMPS-co-AAm) nanocomposite hydrogels with improved mechanical properties exhibit rapid, significant, and reversible electro-response, which show great potential for developing remotely controlled electro-responsive hydrogel systems, such as smart actuators and soft manipulators.

Hydrogels for Medical and Environmental Applications

“…Graphene‐polymer (reduced graphene oxide‐Poly(2‐acrylamido‐2‐methylpropanesulfonic acid‐(PAMPS)) hydrogels were tested for soft actuators with rapid and reversible electro‐response and high mechanical flexibility . The electro‐responsive rate and degree of swelling/deswelling of the hydrogel became fast due to the high conductivity of the reduced graphene homogeneously dispersed in the hydrogels.…”

Autonomous Drug Release Systems with Disease Symptom‐Associated Triggers

“…The controlled release can be triggered by a healthcare provider or the patient (referred to as exogenous stimuli hereafter). The exogenous signals include temperature, light, magnetic field, ultrasound, electric currents, and mechanical forces . Different from passive release and extended/sustained release where the medication releases immediately after being taken by the patient or being applied to the tissues, the drug release rate in controlled release remains at a very low level until the reception of the exogenous stimuli.…”

Preparation and characterization of phosphorylated graphene oxide grafted with poly(L‐lactide) and its effect on the crystallization, rheological behavior, and performance of poly (lactic acid)

“…GO flakes are single atomic layers, made from graphite powder by chemical oxidation and stripping, and can be expanded from nanometer to micron in transverse dimensions. Due to its special mechanical properties and thermal properties, high specific surface area and unique two‐dimensional structure, and so on; compared with clay, carbon nanotubes, graphite, and other polymer matrix composites, it is very suitable for the construction of high‐performance polymer matrix nanocomposites . The surface of GO has a large number of oxygen‐containing functional groups, such as carboxyl (─COOH), hydroxyl (─OH), and epoxy (C─O─C) functional groups, these polar functional groups can make the polymer easy embedding into the GO layer to form PLA nanocomposites, thereby effectively improving the mechanical properties, electrical properties, and crystallization properties of the polymer composite .…”