A piezoelectric adaptive mesh includes multiple piezoelectric fibers that include piezoelectric structures that can act as sensor and/or actuators to enhance a person's comfort. The piezoelectric structures communicate with a controller and/or a software processing system and may identify the position of a user and make adjustments through the actuators to increase user comfort by providing support, assistance, treatment, and/or temperature adjustment.

A biodegradable and biocompatible piezoelectric nanofiber platform for medical implant applications, including a highly sensitive, wireless, biodegradable force sensor for the monitoring of physiological pressures, and a biodegradable ultrasonic transducer for the delivery of therapeutics or pharmaceuticals across the blood-brain barrier.

It is disclosed a composite yarn structure (10) comprising: —a first element (15) comprising a coaxial flexible bi-component monofilament including a conductive component (20) and a thermoplastic component (30) exhibiting piezoelectric properties, —at least a second element (40) twisted around the first element (15), wherein the second element (40) has a lower elasticity with respect to the elasticity of the first element (15) such that, upon elongation of the yarn structure (10) in a first direction, the yarn structure (10) expands in a second direction, whereby the dimensions of the yarn are increased both in first and second directions to generate an additional force on said piezoelectric component of the first element.

An actuator includes a laminate including an elastomer layer and an electrode, in which the laminate has a spiral or concentric shape, pre-distortion is applied to at least one member out of the elastomer layer and the electrode, and area distortion of the at least one member is 10% or larger.

An antibacterial electric charge generation yarn meets requirements (a) to (e) mentioned below simultaneously and suppresses proliferation of bacteria by electric charge generated upon deformation of the yarn: (a) a main component of the yarn is polylactic acid; (b) the yarn is twisted; (c) the yarn has a double torque of 50 T/50 cm or less; (d) the yarn has a single fiber fineness of 0.05 to 5 dtex; and (e) the number of filaments in the yarn is 10 to 400.

In one embodiment, an electroactive material includes a piezoelectric polymer substrate and a conducting polymer coating provided on the substrate.

Provided is a piezoelectric substrate including: an elongate conductor; and an elongate first piezoelectric material helically wound in one direction around the conductor, in which the first piezoelectric material includes an optically active helical chiral polymer (A), the lengthwise direction of the first piezoelectric material and the principal orientation direction of the helical chiral polymer (A) included in the first piezoelectric material are substantially parallel to each other, and the first piezoelectric material has an orientation degree of F. in a range of from 0.5 to less than 1.0, determined from X-ray diffraction measurement by the following Formula (a):
orientation degree F.=(180°−α)/180°  (a) (in Formula (a), α represents a half width of a peak derived from orientation).

An injection-molded article of polymer piezoelectric material includes: a helical chiral polymer constituted by a polymer chain and having a unit cell with an a-axis, a b-axis, and a c-axis as crystal axes, wherein b-axis<a-axis<c-axis in terms of lengths of the crystal axes, the c-axis is parallel to a long chain direction of the polymer chain, the helical chiral polymer is a crystal in which the b-axis is uniaxially oriented, and the injection-molded article has piezoelectricity.

A piezoelectric element includes a piezoelectric layer containing a helical chiral polymer exhibiting piezoelectric properties, a first electrode layer, a second electrode layer, a first coupling portion provided on the first electrode layer, and a second coupling portion provided on the second electrode layer, in which an overlapped portion where the piezoelectric layer, the first electrode layer, and the second electrode layer overlap is circular shaped when viewed along a thickness direction of the piezoelectric layer, and the first coupling portion and the second coupling portion overlap with a center of the overlapped portion when viewed along the thickness direction of the piezoelectric layer.

A piezoelectric device includes a membrane having fibres of a polyhydroxyalkanoate (PHA), having average diameter between 100 nm and 2000 nm, and at least one oxide having piezoelectric properties in a subdivided form having at least one average size between 1 nm and 100 nm. Preferably, the PHA fibres are produced by electrospinning. Advantageously, demonstrating good piezoelectric properties and considering that the piezoelectric device includes PHA, a biodegradable and biocompatible material, the device can be used in biological systems, for example in flexible micro-actuator systems for drug delivery and in the engineering of biological tissues (such as, for example, in pacemaker devices).