1161 results about "Shape-memory polymer" patented technology

This invention relates to a orthopedic implant that comprises a shape memory polymeric material. The orthopedic implant can be fabricated or molded in a desired configuration selected to provide support or tension to bony structures. Examples of implantable devices include spinal rods, bone plates, and bone fixation cords. The orthopedic implant can be deformed to a second configuration different from the first configuration either prior to implantation or after implantation. When desired, the shape memory polymeric material can be induced to revert to it original molded configuration. This can compress the attached bony structure and / or promote arthrodesis.

Catheter assembly including an elongate shaft comprising a thermoplastic polymer such as a thermoplastic shape memory polymer having a pre-selected glass transition temperature (Tg) and a means for heating the thermoplastic polymer, wherein the thermoplastic polymer is in a rubbery state at temperatures above the glass transition temperature and is in a glassy state at temperatures below the glass transition temperature. The elongate shaft may be selectively heated and cooled to provide sufficient flexibility and retention during a medical procedure.

A hood lift mechanism for reversibly increasing the energy absorption capability at appropriate force levels of a vehicle hood includes a vehicle hood; an active material in operative communication with the vehicle hood, wherein the active material comprises a shape memory alloy, a ferromagnetic shape memory alloy, a shape memory polymer, a magnetorheological fluid, an electroactive polymer, a magnetorheological elastomer, an electrorheological fluid, a piezoelectric material, an ionic polymer metal composite, or combinations comprising at least one of the foregoing active materials; and an activation device in operative communication with the active material, wherein the activation device is operable to selectively apply an activation signal to the active material and effect a reversible change in a property of the active material, wherein the reversible change results in an increased clearance distance between the vehicle hood and an underlying component.

A bistable electroactive polymer transducer is provided for electrically actuated deformation of rigid electroactive polymer members. The polymers have glass transition temperatures (Tg) above ambient conditions and turn into rubbery elastomers above Tg and have high dielectric breakdown strength in the rubbery state. They can be electrically deformed to various rigid shapes with maximum strain greater than 100% and as high as 400%. The actuation is made bistable by cooling below Tg to preserve the deformation. The dielectric actuation mechanism includes a pair of compliant electrodes in contact with a dielectric elastomer which deforms when a voltage bias is applied between the pair of electrodes. In some of the configurations, the dielectric elastomer is also a shape memory polymer. The deformations of such bistable electroactive polymers can be repeated rapidly for numerous cycles.