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The nonlinear strain response of soft material–based snap-through systems enables amplified and accelerated force output. However, efficiency of snap-through energy release is challenging to improve because of the inherent trade-off between initial curvature and stiffness. Here, spatial programming of stiffness variation in the azobenzene-functionalized liquid-crystalline polymer (Azo-LCP) addresses this limitation and achieves efficient photomechanical jumping. Introduction of stiffness mismatch induced localized curvature, which preserved the initial curvature and simultaneously enhanced photomechanical strain responsivity. By programming for symmetry of stiffness variation, we achieved directional or vertical jumping via strategic placement of the rigid region, with corresponding stress accumulation behaviors corroborated by finite element simulations. Integration of patterned stiffness variation with geometric asymmetry enabled both vertical and horizontal jumping within a single structure, without compromising performance. This dual-mode jumper also demonstrated sequential and consecutive jumps under continuous light exposure. 

Abstract The development of an organic optical glass, termed, disulfide glass (DSG), is reported as a new polymer for commodity plastic optics and thin film photonic applications. This low‐cost thermoset polymer possesses excellent transparency across the visible and infrared spectrum comparable to the best optical plastic to date, poly(methyl methacrylate), while having superior refractive index (n≈ 1.6). DSG can be fabricated into defect‐free, thick optical glass by bulk addition polymerization of two commodity monomers (sulfur monochloride, 1,3,5‐triallyl isocyanurate) via a new polymerization, sulfenyl chloride inverse vulcanization. The robust mechanical properties and optical clarity of DSG enable fabrication of precision optics (lenses, prisms) via diamond turn machining to demonstrate the manufacturability of DSG for commodity plastic optics. Finally, the synthetic modularity of DSG is demonstrated to form solution processable forms for the fabrication of thin film polymer photonic devices, negative tone polymer photoresists, and micropatterned arrays. 

Abstract The development of a low‐cost photopolymer resin to fabricate optical glass of high refractive index for plastic optics is reported. This new free radically polymerizable photopolymer resin, termed, disulfide methacrylate resin (DSMR) is synthesized by the direct addition of allyl methacrylate to a commodity sulfur petrochemical, sulfur monochloride (S₂Cl₂). The rapid rates of free radical photopolymerization confer significant advantages in preparing high‐quality, bulk optical glass. The low‐cost, optical glass produced from this photopolymer possesses a desirable combination of high refractive index (n ≈ 1.57–1.59), low birefringence (Δn < 10⁻⁴), high glass transition values (T_g ≈ 100 °C), along with optical transparency rivaling, or exceeding that of poly(methyl methacrylate) (PMMA) as indicated by very low optical absorption coefficients (α < 0.05 cm⁻¹at 1310 nm) measured for thick glass DSMR photopolymer samples (diameter (D) = 25 mm; thickness = 1–30 mm). The versatile manufacturability of DSMR photopolymers for both molding and diamond turn machining methods is demonstrated to prepare precision optics and nano‐micropatterned arrays. Finally, large‐scale 3D printing vat photopolymerization of DSMR using high‐area rapid printing digital light processing additive manufacturing is demonstrated.