The detailed mechanical design of a digital mask projection stereolithgraphy system is described for the 3D printing soft actuators. A commercially available, photopolymerizable elastomeric material identified and characterized in its liquid solid form using rheological tensile testing. Its capabilities use directly high degree freedom (DOF), actuators assessed. An outcome ∼40% strain to failure printed elastomer structures. Using resulting properties, numerical simulations pleated actuator...

Despite extensive progress to engineer hydrogels for a broad range of technologies, practical applications have remained elusive due their (until recently) poor mechanical properties and lack fabrication approaches, which constrain active structures simple geometries. This study demonstrates family ionic composite with excellent that can be rapidly 3D‐printed at high resolution using commercial stereolithography technology. The new material design leverages the dynamic reversible nature...

In both biological and engineered systems, functioning at peak power output for prolonged periods of time requires thermoregulation. Here, we report a soft hydrogel-based actuator that can maintain stable body temperatures via autonomic perspiration. Using multimaterial stereolithography, three-dimensionally print finger-like fluidic elastomer actuators having poly-N-isopropylacrylamide (PNIPAm) capped with microporous (~200 micrometers) polyacrylamide (PAAm) dorsal layer. The...

Although soft robotics promises a new generation of robust, versatile machines capable complex functions and seamless integration with biology, the fabrication such soft, three dimensional (3D) hierarchical structures remains significant challenge. Stereolithography (SLA) is an additive manufacturing technique that can rapidly fabricate device architectures required for next these systems. Current SLA materials processes are prohibitively expensive, display little elastic deformation at room...

Abstract Additive manufacturing permits innovative soft device architectures with micron resolution. The processing requirements, however, restrict the available materials, and joining chemically dissimilar components remains a challenge. Here we report silicone double networks (SilDNs) that participate in orthogonal crosslinking mechanisms—photocurable thiol-ene reactions condensation reactions—to exercise independent control over both shape forming process (3D printing) final mechanical...

A family of multi-responsive hydrogel-based actuators capable rapid and controllable motion in response to any immediate environmental change is herein demonstrated towards the 3D-printing functionally graded structures that are encoded with anisotropic swelling behavior.

The rheological parameters required to print viscoelastic nanoparticle suspensions toward tough elastomers via Digital Light Synthesis (DLS) (an inverted projection stereolithography system) are reported. With a model material of functionalized silica nanoparticles suspended in poly(dimethylsiloxane) matrix, the rheological-parameters-guided DLS can structures seven times tougher than those formed from neat polymers. large yield stress and high viscosity associated with these concentration...

Abstract Developments in additive manufacturing have enabled the fabrication of soft machines that can safely interface with humans, creating new applications robotics, wearable technologies, and haptics. However, designing custom inks for 3D printing materials Young’s modulus less than 100 kPa remains a challenge due to highly coupled structure-property-process relationship polymers. Here, we show three-stage material chemistry process based on interpenetrating silicone double networks...

Seamless multimaterial construction is a common motif in animal physiology. Such continuous mechanical gradients remain challenging to reproduce engineered systems, as current resin chemistries typically result single fixed set of properties. As an alternative single-property materials, we introduce thiol-ene-epoxy-based photothermal reaction scheme that produces multimaterials by altering the polymer microstructure within resin. In this system, photodosage during first stage processing...

The ability to control the movement of charged species in circuitry living beings and machines is essential for complex signal processing, computation, and, ultimately, higher functionality. We describe a class photo-ion generators (PIGs) based on non-ionic photoacids that can create large (> 1000x) irreversible changes ionic conductivity under illumination depending PIG species, concentration, solvent. Incorporation PIGs into polyurethane rubber by simple swelling methods yields soft (E...

An acoustic liquefaction approach to enhance the flow of yield stress fluids during Digital Light Processing (DLP)-based 3D printing is reported. This enhanced enables processing ultrahigh-viscosity resins (μapp > 3700 Pa s at shear rates γ˙ = 0.01 s-1 ) based on silica particles in a silicone photopolymer. Numerical simulations acousto-mechanical coupling DLP resin feed system different agitation frequencies predict local velocities exceeding 100 mm transduction 110 . Under these...

This paper reports the rapid 3D printing of tough (toughness, <italic>U</italic>_T, up to 141.6 kJ m⁻³), highly solvated (<italic>ϕ</italic>^water ∼ 60 v/o), and antifouling hybrid hydrogels for potential uses in biomedical, smart materials, sensor applications, using a zwitterionic photochemistry compatible with stereolithography (SLA).

The continuous accumulation of electronic waste is reaching alarming levels necessitating sustainable solutions to mitigate environmental impact. Fabrication the commercial substrates also requires high heat. As an alternative, we propose a series reprocessible based on photopolymerizable polyimides containing degradable ester linkages. We synthesize imide-containing diallyl monomers derived from readily available chemical feedstocks produce high-quality via rapid photopolymerization. Such...

Photopolymerizable and degradable polyimides from liquid resins were developed, using existing economic chemical feedstocks, as flexible substrates to mitigate the e-waste crisis.

Advancements in 3D additive manufacturing have spurred the development of effective patient-specific medical devices. Prior applications are limited to hard materials, however, with few implementations soft devices that better match properties natural tissue. This paper introduces a rapid, low cost, and scalable process for fabricating soft, personalized implants via stereolithography elastomeric polyurethane resin. The effectiveness this approach is demonstrated by designing endocardial...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation M. Cai, A. J. Glover, T. Wallin, D. E. Kranbuehl, H. C. Schniepp; Direct Measurement of the Interfacial Attractions between Functionalized Graphene Polymers in Nanocomposites. AIP Conf. Proc. 2 June 2010; 1255 (1): 95–97. https://doi.org/10.1063/1.3455677 Download citation file: Ris (Zotero) Reference Manager...

Within the general field of polymer grafted or "hairy" nanoparticles, nanoscale ionic materials (NIMs), consisting a soft polymeric canopy bound to well-defined nanoparticle core by an bond, occupy growing niche. They are first example neat, self-suspended fluids nanoparticles (i.e., in absence suspending medium). As such, perennial dispersion challenges associated with nanocomposites minimized while dynamic nature bonds provides opportunities for self-healing behavior. Combining properties...