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This study aims to develop two piezoelectric textile devices formed from different weft knitted fabric rapports (Jersey and Pique) to be applied in the renewable energy’s (RE) area.

Two different weft knitted rapports were produced with polyester (PES). The device developed has five layers: a central of poly(vinylidene fluoride) (PVDF) nonwoven, involved by two insulating layers of PES knitted fabric; and two conductive external layers, made of polypyrrole-coated PES knitted fabric. The piezoelectric textile devices were joined by sewing the five layers of the device.

The FTIR technique confirmed the β-phase in the PVDF nonwoven. This study produced and tested two different textiles devices with piezoelectric behavior, confirmed by the correlated pattern of voltage and tensile stress difference curves, showing the potential application in RE’s and sustainable energies field as smart textiles, such as devices incorporated in garments in the areas of high movement (elbow, knee, foot, fingers and hands, among others), and as an energy generator device

Textile materials with piezoelectric properties promise to advance RE’s developments due to their high material flexibility and sensitivity to the electrical response. The knitted fabric technology presents flexibility due to its construction process. Comparative studies analyzing the electrical response between knitted and woven fabrics have already been realized. However, there is a gap in terms of research scientific research regarding the comparison of the piezoelectric effect in a material that presents different knitted fabric rapports.

The purpose of this study is to analyze the factors affecting the deposition of parts manufactured in poly(lactic acid) with variations in print speed and extrusion temperature. Specimens were analyzed through optical microscopy, mass measurements and flexural tests. The extruder-head evaluation consisted of monitoring the feedstock material displacement on entering the system during deposition under different processing conditions.

To analyze the factors affecting the deposition, parts were manufactured in poly(lactic acid) with variations in print speed and extrusion temperature. Specimens were analyzed through optical microscopy, mass measurements and flexural tests. The extruder-head evaluation consisted of monitoring the feedstock material displacement on entering the system during deposition under different processing conditions.

The results showed low repeatability in the manufacturing of parts, as significant variations in the evaluated responses were found for specimens built under the same process parameters. The main cause for this effect was deposition failure, owing to filament slippage in the extruder head hobbed pulley.

The results found should alert users to the fact that performance tests need to be carried out on every subcomponent of the equipment before conducting experiments on printing parameters. The components of the equipment can influence the final quality of the parts obtained as much as the building parameters and this influence can be significant enough to overlap with that of the process parameters.

The effect of slippage on the deposition quality was quantified and the command loss in the machine control board was identified.