688 results about "Active polymer" patented technology

A surgical stapling instrument particularly suited to endoscopic use articulates an end effector (e.g., stapling and severing) that is actuated by a firing bar. An articulation mechanism in an elongate shaft incorporates electrically actuated polymer (EAP) actuators that laterally support the firing bar so that the firing bar is sufficiently constrained to avoid a blow-out, yet is guided without excessive friction and binding. Thereby, effective, consistent firing is accomplished without an undue increase in firing force required when the end effector is articulated.

A surgical stapling instrument particularly suited to endoscopic use articulates an end effector (e.g., stapling and severing) that is actuated by a firing bar. An articulation mechanism in an elongate shaft incorporates electrically actuated polymer (EAP) actuators that laterally support the firing bar so that the firing bar is sufficiently constrained to avoid a blow-out, yet is guided without excessive friction and binding. Thereby, effective, consistent firing is accomplished without an undue increase in firing force required when the end effector is articulated.

Provided is a bio-sensor system which utilizes radio frequency identification technology and which includes a remote transponder in wireless communication with an implantable on-chip transponder. A power supply collects alternating current voltage pulses from an electro-active polymer generator embedded in muscle tissue for generating power for the on-chip transponder. The power supply is specifically adapted to provide a stable and precise sensor reference voltage to a sensor assembly to enhance the accuracy of measurements of a physiological parameter of a patient. The remote transponder receives data representative of the physiological parameter such as glucose concentration levels. The data is processed and transmitted to the remote transponder by the on-chip transponder. The precision and stability of the sensor reference voltage is enhanced by the specific circuit architecture of a glucose sensor to allow for relatively accurate measurement of glucose concentration levels without the use of a microprocessor.

A method for preparing a functionalized polymer comprising the steps of preparing a pseudo-living polymer by polymerizing conjugated diene monomer with a lanthanide-based catalyst, and reacting the pseudo-living polymer with at least one functionalizing agent defined by the formula (I) where A is a substituent that will undergo an addition reaction with a pseudo-living polymer, R1 is a divalent organic group, R2 is a monovalent organic group, and each R4, which may be the same or different, is a monovalent organic group or a substituent defined by —OR5 where R5 is a monovalent organic group, with the proviso that A, R1, R2, R4, and R5 are substituents that will not protonate a pseudo-living polymer. Also, the functionalized polymer and a vulcanizable composition containing the polymer.

The invention relates to systems that provide variable stiffness and / or variable damping using an electroactive polymer transducer. Systems described herein offer several techniques that provide variable and controlled stiffness and / or damping. A transducer may be implemented using open loop control, thereby providing simple systems that inactively deliver a desired stiffness and / or damping performance. Alternately, closed loop control techniques permit electroactive polymer transducer designs that actively adapt the stiffness and / or damping performance of a system. Further, transducers may be implemented in a device whose stiffness changes with deflection of the polymer.

The present invention relates to improved devices, systems and methods that convert between electrical and mechanical energy. An electroactive polymer transducer converts between electrical and mechanical energy. An active area is a portion of an electroactive polymer transducer. The active area comprises a portion of an electroactive polymer and at least two electrodes that provide or receive electrical energy to or from the portion. The present invention relates to transducers and devices comprising multiple active areas that are in electrically communication. More specifically, the present invention relates to master / slave arrangements for multiple active areas disposed on one or more electroactive polymers. In a master / slave arrangement, a first active area deflects (a ‘master’), and a second active area reacts (a ‘slave’). Communication electronics in electrical communication with electrodes for the first active area and in electrical communication with electrodes for the second active area transfer electrical energy between the two active areas.

A method for preparing a functionalized polymer comprising the steps of preparing a pseudo-living polymer by polymerizing conjugated diene monomer with a lanthanide-based catalyst, and reacting the pseudo-living polymer with at least one functionalizing agent defined by the formula (I) where A is a substituent that will undergo an addition reaction with a pseudo-living polymer, R1 is a divalent organic group, R2 is a monovalent organic group, and each R4, which may be the same or different, is a monovalent organic group or a substituent defined by —OR5 where R5 is a monovalent organic group, with the proviso that A, R1, R2, R4, and R5 are substituents that will not protonate a pseudo-living polymer. Also, the functionalized polymer and a vulcanizable composition containing the polymer.

A method for preparing a functionalized polymer comprising the steps of preparing a pseudo-living polymer by polymerizing conjugated diene monomer with a lanthanide-based catalyst, where said pseudo-living polymer is characterized by having greater than about 85 percent of the polymer in the cis microstructure and less than about 3 percent of the polymer is in the 1,2- or 3,4-microstructure, and reacting the pseudo-living polymer with at least one functionalizing agent defined by the formula (I) or (II) where Z is a substituent that will react or interact with organic or inorganic fillers; R1 is a single bond or a divalent organic group; R2 is a monovalent organic group or a divalent organic group that forms a cyclic organic group with R13 or R14; R3 is a single bond, a divalent organic group, or a trivalent organic group that forms a cyclic organic group with R4 or R5; R13 is a single bond, a divalent organic group, or a trivalent organic group that forms a cyclic organic group with R2 or R14; R4 is a monovalent organic group or a divalent organic group that forms a cyclic organic group with R3 or R5; R14 is a monovalent organic group or a divalent organic group that forms a cyclic organic group with R2 or R13; and R5 is a monovalent organic group or a divalent organic group that forms a cyclic organic group with R3 or R4; with the proviso that each group attached to the imino carbon is attached via a carbon atom and R1, R2 R3, R4, R5, R13, R14 and Z are substituents that will not protonate a pseudo-living polymer.

The invention is concerned with novel cross-linkable, photoactive polymer materials with 3-aryl-acrylic acid esters and amides as well as their use as orienting layers for liquid crystals and for the production of non-structured or structured optical elements and multi-layer systems.

The present invention relates to mechanical-electrical power conversion systems. The systems comprise one or more electroactive polymers that convert between electrical and mechanical energy. When a voltage is applied to electrodes contacting an electroactive polymer, the polymer deflects. This deflection may be converted into rotation of a power shaft included in a motor. Repeated deflection of the polymer may then produce continuous rotation of the power shaft.

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 transducers of the present invention, the dielectric elastomer is also a shape memory polymer. The deformations of such bistable electroactive polymers can be repeated rapidly for numerous cycles. The polymer transducers have such advantages as high energy and power densities, quietness, mechanical compliancy (for shock resistance and impedance matching), high efficiency, lightweight, and low cost.

The present invention relates to transducers, their use and fabrication. The transducers convert between mechanical and electrical energy. Some transducers of the present invention include a pre-strained polymer. The pre-strain improves the conversion between electrical and mechanical energy. The present invention also relates to devices including an electroactive polymer to convert between electrical and mechanical energy. The present invention further relates to compliant electrodes that conform to the shape of a polymer included in a transducer. The present invention provides methods for fabricating electromechanical devices including one or more electroactive polymers.

The present invention provides electroactive polymer transducers that produce out-of-plane deflections. The transducers form a set of surface features based on deflection of an electroactive polymer. The set of surface features may include elevated polymer surface features and / or depressed electrode surface features. Actuation of an active area may produce the polymer deflection that creates one or more surface features. A passive layer may operably connect to a polymer. The passive layer may comprise a thicker and softer material to amplify polymer thickness changes and increase surface feature visibility.

Provided are artificial muscle patches, which are adapted to be implanted adjacent a patient's heart, and artificial sphincter cuffs, which are adapted to be implanted around a body lumen, such as the urethra, the anal canal, or the lower esophagus. The devices of the present invention comprise: (a) one or more electroactive polymer actuators; and (b) a control unit for electrically controlling the one or more electroactive polymer actuators to expand or contract the devices.

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.

Methods and apparatus for the direct deposition or patterning of biological materials and compatible biomaterials. The method is capable of depositing biological materials and biomaterials in a computer defined pattern, and uses aerodynamic focusing of an aerosol stream to deposit mesoscale patterns onto planar or non-planar targets without the use of masks or modified environments. The aerosolized compositions may be processed before deposition (pre-processing) or after deposition on the target (post-processing). Depositable materials include, not are not limited to conductive metal precursors, nanoparticle metal inks, dielectric and resistor pastes, biocompatible polymers, and a range of biomolecules including peptides, viruses, proteinaceous enzymes, extra-cellular matrix biomolecules, as well as whole bacterial, yeast, and mammalian cell suspensions. The targets may be planar or non-planar, and are optionally biocompatible. Applications include biosensor rapid prototyping and microfabrication, lab-on-chip manufacturing, biocompatible electroactive polymer development (ambient temperature bio-production of electronic circuitry), and various additive biomaterial processes for hybrid BioMEMS, Bio-Optics, and microfabrication of biomedical devices.