Orthogonal photochemistry-assisted printing of 3D tough and stretchable conductive hydrogels

Abstract3D-printing tough conductive hydrogels (TCHs) with complex structures is still a challenging task in related fields due to their inherent contrasting multinetworks, uncontrollable and slow polymerization of conductive components. Here we report an orthogonal photochemistry-assisted printing (OPAP) strategy to make 3D TCHs in one-pot via the combination of rational visible-light-chemistry design and reliable extrusion printing technique. This orthogonal chemistry is rapid, controllable, and simultaneously achieve the photopolymerization of EDOT and phenol-coupling reaction, leading to the construction of tough hydrogels in a short time (tgel ~30 s). As-prepared TCHs are tough, conductive, stretchable, and anti-freezing. This template-free 3D printing can process TCHs to arbitrary structures during the fabrication process. To further demonstrate the merits of this simple OPAP strategy and TCHs, 3D-printed TCHs hydrogel arrays and helical lines, as proofs-of-concept, are made to assemble high-performance pressure sensors and a temperature-responsive actuator. It is anticipated that this one-pot rapid, controllable OPAP strategy opens new horizons to tough hydrogels.

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Waterproof, thin, high-performance pressure sensors-hand drawing for underwater wearable applications

Science and Technology of Advanced Materials ◽

10.1080/14686996.2021.1961100 ◽

2021 ◽

Author(s):

Chi Cuong Vu ◽

Jooyong Kim

Keyword(s):

High Performance ◽

Pressure Sensors ◽

Performance Pressure

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Tunable In Situ 3D-Printed PVDF-TrFE Piezoelectric Arrays

Sensors ◽

10.3390/s21155032 ◽

2021 ◽

Vol 21 (15) ◽

pp. 5032

Author(s):

Alec Ikei ◽

James Wissman ◽

Kaushik Sampath ◽

Gregory Yesner ◽

Syed N. Qadri

Keyword(s):

3D Printing ◽

Polyvinylidene Fluoride ◽

Vinylidene Fluoride ◽

Mechanical Strain ◽

Pressure Sensors ◽

Strain Ratio ◽

Ex Situ ◽

Order Of Magnitude ◽

3D Printed

In the functional 3D-printing field, poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) has been shown to be a more promising choice of material over polyvinylidene fluoride (PVDF), due to its ability to be poled to a high level of piezoelectric performance without a large mechanical strain ratio. In this work, a novel presentation of in situ 3D printing and poling of PVDF-TrFE is shown with a d33 performance of up to 18 pC N−1, more than an order of magnitude larger than previously reported in situ poled polymer piezoelectrics. This finding paves the way forward for pressure sensors with much higher sensitivity and accuracy. In addition, the ability of in situ pole sensors to demonstrate different performance levels is shown in a fully 3D-printed five-element sensor array, accelerating and increasing the design space for complex sensing arrays. The in situ poled sample performance was compared to the performance of samples prepared through an ex situ corona poling process.

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Integrating 3D printing and self-assembly for layered polymer/nanoparticle microstructures as high-performance sensors

Journal of Materials Chemistry C ◽

10.1039/d0tc02660c ◽

2020 ◽

Vol 8 (28) ◽

pp. 9495-9501 ◽

Cited By ~ 1

Author(s):

Sayli Jambhulkar ◽

Weiheng Xu ◽

Rahul Franklin ◽

Dharneedar Ravichandran ◽

Yuxiang Zhu ◽

...

Keyword(s):

3D Printing ◽

Self Assembly ◽

High Performance ◽

Chemical Sensor ◽

Carbon Nanofiber ◽

Polymer Nanoparticle ◽

3D Printed

A 3D printed, preferentially aligned, and alternate-layered polymer–carbon nanofiber microstructure for a high-performance chemical sensor has been fabricated.

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A flexible pressure sensor based on an MXene–textile network structure

Journal of Materials Chemistry C ◽

10.1039/c8tc04893b ◽

2019 ◽

Vol 7 (4) ◽

pp. 1022-1027 ◽

Cited By ~ 37

Author(s):

Tongkuai Li ◽

Longlong Chen ◽

Xiang Yang ◽

Xin Chen ◽

Zhihan Zhang ◽

...

Keyword(s):

Network Structure ◽

Pressure Sensor ◽

High Performance ◽

Pressure Sensors ◽

Wearable Electronics ◽

Physiological Signal ◽

Signal Perception ◽

Performance Pressure ◽

Human Machine Interfaces ◽

Flexible Pressure Sensor

High-performance pressure sensors have attracted considerable attention recently due to their promising applications in touch displays, wearable electronics, human–machine interfaces, and real-time physiological signal perception.

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The Surface Characterisation of Fused Filament Fabricated (FFF) 3D Printed PEEK/Hydroxyapatite Composites

Polymers ◽

10.3390/polym13183117 ◽

2021 ◽

Vol 13 (18) ◽

pp. 3117

Author(s):

Krzysztof Rodzeń ◽

Mary Josephine McIvor ◽

Preetam K. Sharma ◽

Jonathan G. Acheson ◽

Alistair McIlhagger ◽

...

Keyword(s):

3D Printing ◽

Photoelectron Spectroscopy ◽

High Performance ◽

Secondary Ion Mass Spectrometry ◽

Fused Filament Fabrication ◽

Surface Characterisation ◽

X Ray ◽

3D Printed

Polyetheretherketone (PEEK) is a high-performance thermoplastic polymer which has found increasing application in orthopaedics and has shown a lot of promise for ‘made-to-measure’ implants via additive manufacturing approaches. However, PEEK is bioinert and needs to undergo surface modification to make it at least osteoconductive to ensure a more rapid, improved, and stable fixation that will last longer in vivo. One approach to solving this issue is to modify PEEK with bioactive agents such as hydroxyapatite (HA). The work reported in this study demonstrates the direct 3D printing of PEEK/HA composites of up to 30 weight percent (wt%) HA using a Fused Filament Fabrication (FFF) approach. The surface characteristics and in vitro properties of the composite materials were investigated. X-ray diffraction revealed the samples to be semi-crystalline in nature, with X-ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry revealing HA materials were available in the uppermost surface of all the 3D printed samples. In vitro testing of the samples at 7 days demonstrated that the PEEK/HA composite surfaces supported the adherence and growth of viable U-2 OS osteoblast like cells. These results demonstrate that FFF can deliver bioactive HA on the surface of PEEK bio-composites in a one-step 3D printing process.

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Novel high-performance pressure sensors using double SOI structures

TRANSDUCERS '91: 1991 International Conference on Solid-State Sensors and Actuators. Digest of Technical Papers ◽

10.1109/sensor.1991.148971 ◽

2002 ◽

Cited By ~ 1

Author(s):

G.-S. Chung ◽

S. Kawahito ◽

M. Ashiki ◽

M. Ishida ◽

T. Nakamura

Keyword(s):

High Performance ◽

Pressure Sensors ◽

Performance Pressure

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A Novel Route to Fabricate High-Performance 3D Printed Continuous Fiber-Reinforced Thermosetting Polymer Composites

Materials ◽

10.3390/ma12091369 ◽

2019 ◽

Vol 12 (9) ◽

pp. 1369 ◽

Cited By ~ 13

Author(s):

Yueke Ming ◽

Yugang Duan ◽

Ben Wang ◽

Hong Xiao ◽

Xiaohui Zhang

Keyword(s):

3D Printing ◽

Polymer Composites ◽

High Performance ◽

Flexural Modulus ◽

Shape Preservation ◽

Fiber Reinforced ◽

Continuous Fiber ◽

Research Attention ◽

3D Printed ◽

Thermosetting Polymer

Recently, 3D printing of fiber-reinforced composites has gained significant research attention. However, commercial utilization is limited by the low fiber content and poor fiber–resin interface. Herein, a novel 3D printing process to fabricate continuous fiber-reinforced thermosetting polymer composites (CFRTPCs) is proposed. In brief, the proposed process is based on the viscosity–temperature characteristics of the thermosetting epoxy resin (E-20). First, the desired 3D printing filament was prepared by impregnating a 3K carbon fiber with a thermosetting matrix at 130 °C. The adhesion and support required during printing were then provided by melting the resin into a viscous state in the heating head and rapidly cooling after pulling out from the printing nozzle. Finally, a powder compression post-curing method was used to accomplish the cross-linking reaction and shape preservation. Furthermore, the 3D-printed CFRTPCs exhibited a tensile strength and tensile modulus of 1476.11 MPa and 100.28 GPa, respectively, a flexural strength and flexural modulus of 858.05 MPa and 71.95 GPa, respectively, and an interlaminar shear strength of 48.75 MPa. Owing to its high performance and low concentration of defects, the proposed printing technique shows promise in further utilization and industrialization of 3D printing for different applications.

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