Smart material

About: Smart material is a research topic. Over the lifetime, 3704 publications have been published within this topic receiving 74280 citations. The topic is also known as: intelligent material & responsive material.

Mechanical and shape recovery properties of shape memory polymer composite embedded with cup-stacked carbon nanotubes

Abstract: This study investigated the mechanical and shape recovery properties of a styrene-based shape memory polymer composite reinforced by cup-stacked carbon nanotubes. Due to their unique morphology, cu...

Smart Drug Release Systems Based on Stimuli-Responsive Polymers

Abstract: Stimuli-responsive polymers could respond to external stimuli, such as temperature, pH, photo-irradiation, electric field, biomolecules in solution, etc., which further induce reversible transformations in the structures and conformations of polymers, providing an excellent platform for controllable drug release, while the accuracy of drug delivery could obtain obvious improvement in this system. In this review, recent progresses in the drug release systems based on stimuli-responsive polymers are summarized, in which drugs can be released in an intelligent mode with high accuracy and efficiency, while potential damages to normal cells and tissues can also be effectively prevented owing to the unique characteristics of materials. Moreover, we introduce some smart nanoparticles-polymers conjugates and drug release devices, which are especially suitable for the long-term sustained drug release.

Diving–Surfacing Smart Locomotion Driven by a CO2-Forming Reaction, with Applications to Minigenerators

Abstract: Harvesting energy from environment has attracted increasing attention for its potential applications in fabricating minigenerator. However, most studies in the fabrication of mini- or nanogenerators are based on the concept of piezoelectricity or triboelectrification while few of the reports paid attention to the classical theory of Faraday's law. Herein, a pH responsive smart surface is combined with the reaction between CaCO3 and HCl to develop a new minigenerator, which can convert mechanical energy generated from the chemical reaction into electrical energy through cutting magnetic lines with moving conductive lines. The conductive lines are connected with a smart device consisting of a pH-responsive cube, a hydrophobic cube, and a quartz cell window; the device can perform diving-surfacing cycled motions with an intelligent initiation through the adjustment of the solution. The device can surface through gathering CO2 bubbles from the reaction between CaCO3 and HCl and dive by releasing the bubbles on the water/air interface. Moreover, the results demonstrate that the inert CO2 was nonhazardous to the smart surfaces, which is meaningful for durable electricity generation.

Superhydrophobic heterogeneous graphene networks with controllable adhesion behavior for detecting multiple underwater motions

Abstract: Smart materials with underwater motion detection have become a popular research topic with the development of ocean exploration. Herein, a heterogeneous polydimethylsiloxane/open-cell graphene network (PDMS/OCGN) with a micro–nanoscale hierarchical structure is fabricated via a simple inverse drying method. The PDMS/OCGN has a special microstructure due to the PDMS-coated surface and the uncoated interior, which enables the material to exhibit both strong superhydrophobicity and high electrical conductivity simultaneously. In addition, the adhesive force of PDMS/OCGNs for water droplets can easily be controlled from 70.6 μN to 34.0 μN by adjusting the coating content. On this basis, the lossless transportation of water microdroplets is achieved in this paper. By means of the typical underwater state and deformable network of PDMS/OCGNs, for the first time, a superhydrophobic material with rapid sensing capability for immersion and emersion processes, owing to the abrupt change in its resistance, is reported. More importantly, the vertical dive and horizontal movement in water can also be detected in real time. Furthermore, the PDMS/OCGN can identify the diving depth and moving speed via the degree of change in resistance. Therefore, this multifunctional PDMS/OCGN may be an excellent candidate for the fabrication of underwater sensing devices.

Electroactive textile actuators for wearable and soft robots

Abstract: Smart fabrics offer the potential for a new generation of soft robotics, reactive clothing and wearable technologies through the fusion of smart materials, textiles and electrical circuitry. In this work we present a range of smart fabrics and reactive textiles for soft robotics. We investigate conductive stretchable textiles for the fabrication of dielectric elastomer (DE) and electroadhesive (EA) actuators. These include a planar DE actuator, a bending DE actuator, and an EA actuator. The textile DE actuator generated a relative area expansion of 16.4 % under 9 kV while the bending actuator generated a relative expansion of 5 % under 6 kV. The EA actuator generated a shear adhesive force of 0.14 kPa at less than 5 kV. This work shows the feasibility of using conductive fabrics for soft actuation technologies. Conductive textiles have the potential to deliver simple, comfortable, multi-function and wearable soft robotic devices and complete soft robots.