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Sugar casting is a simple and cost-effective direct method of generating polymer foams. By incorporating grains directly into mixtures of polymer and piezoelectric nanoparticles it is possible to create highly compliant materials with excellent piezoelectric properties. In this work, we use the sugar casting method in combination with spin coating to prepare a highly sensitive and flexible 0-3 piezoelectric polymer thin film membranes with a layer thickness of 20 to 190 µm. Porosities and elasticity are tuned by simply adjusting the sugar/polymer mass ratio. The expected outcome of this research was improvements to the piezoelectric voltage, the g33 measure, due to the increased compliance of the material, however iezoelectric composite membranes with high concentrations of PMN-PT also demonstrated gains in piezoelectric coupling, the d33 measure, when cast with high volume fractions of sugar. A remarkably high d33 coefficient of 69 pm/V was measured using the laser vibrometer technique. These innovative materials were developed as broadband ultrasonic sensors for partial discharge detection in undersea cables, however they have potential uses in energy scavenging platforms, biosensors, and acoustic actuators, among others.

The determination of the mechanical properties of materials is predominantly undertaken using destructive approaches. Such approaches are based on well-established mathematical formulations where a physical property of the material is measured as a function of an input under controlled conditions provided by some machine, such as load–displacement curves in indentation tests and stress–strain plots in tensile testing. The main disadvantage of these methods is that they involve destruction of samples as they are usually tested to failure to determine the properties of interest. This means that large sample sizes are required to obtain statistical certainty, a condition that, depending on the material, may mean the process is both time consuming and expensive. In addition, for rapid prototyping and small-batch manufacturing of polymers, these techniques may be inappropriate either due to excessive cost or high polymer composition variability between batches. In this paper we discuss how the Euler–Bernoulli beam theory can be exploited for experimental, non-destructive assessment of the mechanical properties of three different 3D-printed materials: a plastic, an elastomer, and a hydrogel. We demonstrate applicability of the approach for materials, which vary by several orders of magnitude of Young’s moduli, by measuring the resonance frequencies of appended rectangular cantilevers using laser Doppler vibrometry. The results indicate that experimental determination of the resonance frequency can be used to accurately determine the exact elastic modulus of any given 3D-printed component. We compare the obtained results with those obtained by tensile testing for comparison and validation.