An electroactive polymer transducer including a dielectric elastomer material having a first configuration with a first spring constant and a second configuration with a second spring constant and where the second spring constant is lower than the first spring constant.

A polymeric piezoelectric material, comprising at least two regions: a region H, which is an oriented polymeric piezoelectric region that includes an optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, the region H having a crystallinity of from 20% to 80% and having a standardized molecular orientation-of from 3.5 to 15.0; and a region L, which is a low orientation region that includes the optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, the region L being present near at least part of an end portion of the region H, having an average width when viewed from a normal direction with respect to the principal plane of the region H of from 10 μm to 300 μm, and having a retardation is 100 nm or less.

An electroactive device may include (1) an electroactive polymer element having a first surface and a second surface opposing the first surface, (2) a primary electrode abutting the first surface, and (3) a secondary electrode abutting the second surface. The electroactive polymer element may be transformed from an initial state to a deformed state and may achieve substantially uniform strain by the application of an electrostatic field produced by a potential difference between the electrodes. Various other devices, systems, and methods are also disclosed.

A piezoelectric polyvinylidene fluoride (PVDF) material, a method for manufacturing the same, and a fingerprint recognition module are provided. The polyvinylidene PVDF material includes PVDF, a first solvent, a second solvent, a fluorosurfactant, and an inducing material. Material of the inducing material is one of carbon nanotubes, carbon black, and gold nanorods. Because of the high anisotropy of the inducing material, molecular orientation of the PVDF material is induced, thereby improving piezoelectric performance of the piezoelectric PVDF material. Problems of conventional piezoelectric PVDF materials, which are used in ultrasonic fingerprint recognition modules, such as poor piezoelectric performance and high-energy loss are improved.

Disclosed herein is a buckling actuator, comprising: a first electrode; a second electrode; and a film of a dielectric elastomeric material having a first surface and a second surface sandwiched between the first and second electrodes, wherein the material is formed by the random block copolymerisation of a polymeric material comprising silicon or nitrogen atoms that has two or more acrylate or vinyl end groups, and a polar polymeric material having two or more acrylate or vinyl end groups. Also disclosed herein is a method of forming said dielectric elastomeric material.

Provided is a polymeric piezoelectric film containing an optically active helical chiral polymer (A) having a weight average molecular weight of from 50,000 to 1,000,000, in which a crystallinity obtained by a DSC method is from 20% to 80%, and the product of the crystallinity and a standardized molecular orientation MORc when a reference thickness measured by a microwave transmission-type molecular orientation meter is set to 50 μm is from 25 to 700, and in which a surface roughness of at least one plane in terms of a non-contact three-dimensional surface roughness Sa measured by a confocal laser microscope is from 0.040 μm to 0.105 μm.

An object of the present invention is to provide a laminated piezoelectric element in which piezoelectric films are laminated, capable of easily performing connection of an electrode layer of each piezoelectric film and an external device. The piezoelectric film includes a piezoelectric layer and a laminated sheet in which an electrode layer and a protective layer are laminated, piezoelectric layers are arranged between the laminated sheets facing the electrode layer, the laminated sheet includes a protruding portion protruding from the piezoelectric layer, the protruding portion is provided with a lead-out wire attached to a surface between the electrode layer and the protective layer, and the object is achieved by contacting the lead-out wire and connecting electrode layers having a same polarity of each piezoelectric film.

The invention relates to methods and compositions for preparing silk-based piezoelectric materials and methods for increasing piezoelectricity in silk matrices.

An apparatus comprising a frame and a pressure sensitive adhesive applied to at least a portion of the frame, where the pressure sensitive adhesive is arranged to bond a pre-strained film to the frame is disclosed. A method of making the apparatus also is disclosed. Also disclosed is a method of preparing a stretch frame for manufacturing electroactive polymer devices thereon.

A piezoelectric sensor, a manufacturing method thereof and an electronic device are provided. The piezoelectric sensor includes a substrate, an active layer, the active layer being disposed at a side of the substrate: a first electrode, the first electrode being disposed at a side of the active laver a wav from the substrate, and the first electrode including a plurality of sub-electrodes disposed at intervals: a piezoelectric layer, the piezoelectric layer being disposed at a side of the first electrode away from the active layer; and a second electrode, the second electrode being disposed at a side of the piezoelectric layer away from the first electrode. The active layer is configured to be capable of switching between an insulating state and a conducting state, and in the conducting state the active layer is capable of conducting the plurality of sub-electrodes.