Andrzej Pepłowski | CEZAMAT, Warsaw University of Tech..: How do you stop elastic TPU and carbon pastes from phase-separating and clogging your manufacturing screens?
12:20 - 14:20
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How do you stop elastic TPU and carbon pastes from phase-separating and clogging your manufacturing screens?
Developing high-performance electrochemical sensors on elastic substrates requires deep control over the formulation's microstructural behavior during shear. When printing carbon-based pastes, carbon particles tend to agglomerate under specific fluid conditions, which can be leveraged to drive the self-assembly of highly active, unblocked sensing surfaces. However, replicating this behavior with gold nanoparticles or transferring these formulations to highly elastic binders presents severe rheological challenges.
Using thermoplastic polyurethane (TPU) as an elastic binder is notoriously difficult due to its tendency to phase-separate from its solvent and plasticizer under mechanical stress. During continuous screen printing, this high shear stress causes the TPU to destabilize, leading to solvent evaporation and particulate filtration that quickly blocks the screen mesh.
Overcoming these scaling bottlenecks requires carefully adjusting the composite's flow equation by introducing specific secondary additives. By controlling the relationship between shear stress, surface tension, and particulate geometry, engineers can stabilize the suspension and ensure uniform deposition during high-volume production runs.
In this short video, you can learn:
* How carbon particle agglomeration and self-assembly can be harnessed to optimize electrochemical sensing.
* The mechanical and chemical reasons why elastic TPU binders phase-separate and clog printing screens under shear stress.
* How to manipulate composite flow equations and particle geometries to stabilize ink suspensions for high-volume manufacturing.
📋 **Clip Abstract** The speaker discusses the microstructural physics of printing carbon and TPU-based elastic composites for electrochemical biosensors. He details the rheological issues of phase separation and screen clogging, emphasizing how formulating flow behavior is key to successful scaling.
#InkRheology, #TPUBinders, #ScreenPrinting, #ElectrochemicalSensors, #PrintedElectronics, #WearableBiosensors
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08:05 - 10:45
Why does fine-tuning a single printing parameter break your entire wearable medical device?
Why does fine-tuning a single printing parameter break your entire wearable medical device?
The standard product development workflow for flexible, printed bio-wearables typically follows a simple, linear path: designing the layout, selecting off-the-shelf materials, executing the printing process, and conducting final operations. However, this sequential approach often fails because the physics of printed electronics are highly non-linear and coupled. A minor change in a single fabrication setting propagates unpredictable variations across multiple material properties.
For instance, adjusting the squeegee pressure during screen printing does not just alter layer thickness; it directly impacts the ink's shear rate, pigment agglomeration, and drying kinetics. These structural changes can subsequently degrade the device's electrical sensitivity, signal-to-noise ratio, and even its long-term biocompatibility on human skin.
To successfully transition from laboratory prototypes to commercially scalable medical products, developers must abandon linear pipelines in favor of a holistic, multi-disciplinary loop. This paradigm shift requires integrating material science, rheological characterization, and operational bio-compatibility metrics concurrently at every single phase of the R&D process.
In this short video, you can learn:
* Why linear R&D workflows fail when scaling up printed electronic sensors.
* How minor screen-printing adjustments (like squeegee pressure) cascade into system-wide material failures.
* The importance of a holistic design loop that links material rheology to end-use biological performance.
📋 **Clip Abstract** This clip challenges the traditional, linear product development pipeline used for printed wearable medical devices. The speaker explains how single-parameter adjustments in printing trigger complex cascades that alter material properties, calling for a deeply integrated, non-linear R&D model.
#ScreenPrinting, #InkRheology, #PrintedSensors, #FlexibleElectronics, #WearableMedTech, #Bioelectronics
14:48 - 16:00
How can you continuously record high-fidelity ECG signals directly from a wet, beating heart during open surgery?
How can you continuously record high-fidelity ECG signals directly from a wet, beating heart during open surgery?
Traditional rigid ECG electrodes are fundamentally incapable of maintaining stable electrical contact with wet, actively moving internal tissues during major surgical procedures. To address this clinical limitation, researchers have developed an ultra-conformable, graphene-based wet-adhesive patch designed to stick directly to the epicardium. This interface allows for continuous, high-fidelity electrophysiological recording during active surgical interventions.
The material science of this interface relies on inherent wet adhesion and high electrical conductivity without needing artificial insulation barriers. Unlike conventional micro-devices that require complex parylene-C encapsulation to prevent short-circuiting in physiological fluids, this pure graphene composite remains stable and functional on its own.
Successfully tested in highly demanding large-animal veterinary open-heart surgeries, these direct-contact electrodes demonstrate excellent biocompatibility and mechanical compliance. This technological leap provides clinical teams with real-time, noise-free cardiac mapping that was previously impossible using standard surface monitoring.
In this short video, you can learn:
* The clinical and mechanical limitations of traditional rigid ECG electrodes during open-heart surgeries.
* How conformable graphene-based wet adhesives bond directly to wet, dynamic cardiac tissue without external packaging.
* Why this advanced material eliminates the need for parylene encapsulation in wet biological environments.
📋 **Clip Abstract** This clip highlights a breakthrough in surgical monitoring using an ultra-conformable, graphene-based adhesive patch applied directly to the heart. The speaker shows how this highly biocompatible interface delivers stable, real-time ECG signals from wet tissue without requiring protective parylene coatings.
#GrapheneBioelectronics, #EpicardialECG, #WetAdhesiveElectrodes, #EncapsulationFreeSensors, #Bioelectronics, #FlexibleElectronics