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Current polymer network design suffers from intrinsic trade-offs, where polymer networks with high modulus often turn out to be in short of stretchability or fracture toughness. Here, we show a novel polymer network design through polymer-nanoparticle alternating hybrids that enable integrating the non-polymeric colloid deformation into polymer network design. The new class of polymer network exhibits colloidal yielding at small deformation before conformational change at higher elongation ratios, enabling simultaneous achievement of high Young’s modulus of E≈10-50 MPa, high yield strength of σ_Y~ 3-5 MPa, large stretchability of λ~7-10, and high fracture energy density of Γ~30 MJ/m^3. These results demonstrate a successful strategy to decouple the molecular mechanics for yield from that for stretchability or toughness, leading to new polymer networks design. 

Kerr resonators generate stable frequency combs and ultrashort pulses with applications in telecommunications, biomedicine, and metrology. Chirped pulse solitons recently observed in normal dispersion Kerr resonators with an intracavity spectral filter can enable new material design freedom, reduced fabrication requirements, and the potential for improved ultrashort pulse peak powers. This study examines the design and formation properties of chirped pulse Kerr solitons essential to enable these advances. First, prior theoretical predictions that chirped pulse solitons are relatively insensitive to cavity loss and the strength of the dispersion map are experimentally validated. The loss insensitivity property is applied to demonstrate high-energy pulses in a cavity with a large output coupling and the map insensitivity property is applied to demonstrate femtosecond pulses, for the first time to the best of our knowledge, from chirped pulse solitons in a dispersion-mapped cavity with small net-normal dispersion. The relationship between chirped pulses and bright pulses enabled by higher order dispersion is examined with respect to pulse formation, cavity design parameters, and performance properties. Finally, guidelines for additional improvements are detailed for chirped pulse soliton-based high-performance pulse generation.

 

Spontaneous formation of concentric lamellae was observed in self‐assembling giant surfactants consisting of a fluorinated polyhedral oligomeric silsesquioxane (FPOSS) head and flexible polymer tail(s). Owing to the asymmetrical sizes of the head and tail blocks and the rectangular molecular interface, the giant surfactants assumed a truncated‐wedge‐like molecular shape, which induced morphological curvature during self‐assembly, thus resulting in the formation of curved and concentric lamellae. These curved/concentric lamellae were observed in FPOSS‐based giant surfactants with different architectures and compositions. The spontaneous curvature formation not only promotes our fundamental understanding of assembly principles, but also provides a promising and efficient approach to the fabrication of a wide range of high‐performance devices.