Application Of Shape Memory Materials Research Articles

Shape memory textiles for smart compression management for chronic venous disorders – A review

In conventional compression treatment using bandage or stocking, always there has been a problem of achieving and maintaining the recommended compression gradient and level. In addition, these devices are incapable of offering dynamic (massaging) compression, often preferred especially for senior and non-active patients to improve blood flow. To overcome these challenges, the application of shape memory materials is proven to provide a dynamic or selective pressure change directly on the limb. Memory material-based stockings or bandage have the potential to tackle the drawbacks of existing stockings by allowing users to modify pressure levels externally as needed during compression therapy, i.e. as a smart wound care device. This paper reports the consolidated information on traditional compression systems, their challenges, and modern methods involving active compression bandages based on smart materials technology (via shape memory polymer or shape memory alloy), which develop intermittent active pressure to alleviate the symptoms of lower limb problems.

Retentive drug delivery systems based on shape memory materials

ABSTRACTRetentive drug delivery systems are intended for prolonged residence and release inside hollow organs of the body, in pursuit of either local or systemic therapeutic goals. Because of the relatively long‐lasting period of time they could cover during operation, a primary advantage arising from their use would lie in reduced dosing frequency, thereby improving the overall adherence of patients to prescribed medication regimens. The treatment of numerous pathologies that affect the urinary bladder and the stomach could especially benefit from viability of such delivery technologies. Moreover, by making use of effective gastroretentive dosage forms, the bioavailability of drugs that are preferably absorbed from the upper gastrointestinal tract could be increased. Expansion of devices following administration is often exploited for retention purposes, and several formulation strategies have been proposed in this respect. Innovative applications of shape memory materials have also been explored, highlighting the great inherent potential for facing the challenges involved. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48798.

Fabrication of Smart Shape Memory Fluorosilicon Thermoplastic Vulcanizates: The Effect of Interfacial Compatibility and Tiny Crystals

To expand the application of shape memory materials in situations where elevated temperature and corrosion resistance are required, novel heat-triggered shape memory (HSM) fluorosilicon thermoplast...

Numerical research of biomechanical system with SMA prosthesis

In this paper the modelling of special biomechanical mechanism and application of shape memory materials are presented. The model of the human middle ear is made as multibody system. The basic 3dof ear model of the healthy middle ear is modified to represent the damaged ear. A damaged of the ossicular chainis taken into account by adding gap in visco-elastic joints. In addition, an attempt of the ossicles chain reconstruction through prosthesis made of shape memory alloy is presented. Moreover, a new description of the hysteresis sub-loop which characterise prosthesis material is proposed. Finally, dynamic responses of healthy, damaged and reconstructed models of the middle ear are compared by quality index.

Mechanical behaviors and biomedical applications of shape memory materials: A review

A shape memory material (shape memory alloy (SMA) or shape memory polymer (SMP)) can experience large deformation and recover its original shape when exposed to a specific external stimulus. Shape memory materials have drawn significant attention due to their applications in biomedical devices, which typically require appropriate mechanical biocompatibility, including elastic modulus compatibility, adequate strength and fracture toughness, and superior fatigue resistance. In this review, we provide an overview of mechanisms and biomedical applications of some common SMAs and SMPs, experimental evidences on their mechanical biocompatibility, and some key aspects of computational modeling. Challenges and progress in developing new shape memory materials for biomedical applications are also presented.

Actuation of shape-memory colloidal fibres of Janus ellipsoids.

Many natural micrometre-scale assemblies can be actuated to control their optical, transport and mechanical properties, yet such functionality is lacking in colloidal structures synthesized thus far. Here, we show with experiments and computer simulations that Janus ellipsoids can self-assemble into self-limiting one-dimensional fibres with shape-memory properties, and that the fibrillar assemblies can be actuated on application of an external alternating-current electric field. Actuation of the fibres occurs through a sliding mechanism that permits the rapid and reversible elongation and contraction of the Janus-ellipsoid chains by ~36% and that on long timescales leads to the generation of long, uniform self-assembled fibres. Colloidal-scale actuation might be useful in microrobotics and in applications of shape-memory materials.

Application of shape memory materials in fluid sealing technology

PurposeThe purpose of this paper is to present short characteristics of shape memory alloys (SMA) and shape memory polymers (SMP) and some examples of application of these materials in industrial sealing technology.Design/methodology/approachIn this paper, short characteristic of shape memory materials and design examples of applying them in industrial sealing technology such as: tube coupling in hydraulic systems, flanged pipe connections, lip radial seal, mechanical face seal, soft gland packing, magnetic fluid seal, and in bearing seal system for drill bit, are given.FindingsThe paper provides information about innovative fluid seal designs based on particular properties of the shape memory materials, applied in stationary joints, and rotary equipments. These new solutions provide often to simplify seal design, their miniaturization, increase of tightness, and reduction of operating costs.Originality/valueThis paper offers some new fluid seal designs based on the shape memory materials and their practical application in industrial sealing technology.