High sensitivity capacitive pressure sensors can be created with bottlebrush dielectric layers that overcome the limitations of traditional polymeric materials.

We demonstrate a universal approach to form bottlebrush polymer networks in both bulk and thin films by photo-crosslinking mixtures of well-defined bottlebrush precursors and bis-benzophenone-based additives. This strategy is compatible with a wide variety of different side-chain chemistries including poly­(acrylates), poly­(ethers), poly­(esters), and poly­(siloxanes) due to the indiscriminate C–H abstraction behavior of benzophenone upon exposure to ultraviolet light. The appropriate choice of molecular “linker” that bridges benzophenones is critical to solubilize the additive in a given bottlebrush precursor at room temperature without a solvent. Importantly, homogeneous mixtures can be achieved using two distinct types of linkers: telechelic polymers matched to the bottlebrush side-chain chemistry or small-molecule branched alkyl derivatives that are often synthetically more accessible. As evidenced by in situ UV shear rheology, the curing kinetics and mechanical properties of these amorphous or semicrystalline networks are controlled by bottlebrush precursor chemistry, architecture, and crosslinker loading. The influence of elastically effective and ineffective crosslinks, which arise in tandem from the statistical nature of benzophenone-induced radical reactions, is quantitatively captured by introducing a general model that relates crosslinker concentration and shear modulus. These results provide a conceptual framework that can be used to conveniently synthesize bottlebrush networks with tailored properties.

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feature sizes and high aspect ratios for pattern transfer can be obtained. [6][7][8] Typically, such BCP thin films are prepared by spin-coating a dilute BCP solution onto silicon (Si) substrates. However, these as-cast BCP thin films exhibit a locally segregated, disordered morphology. [9][10][11] Although perpendicular lamellar structures can be obtained by various annealing processes, high defectivity in the resultant thin films reduces the potential for industrial applications. Furthermore, although chemical and physical guides can be used to alleviate the thin film defectivity, [6,[12][13][14][15] BCP thin films that can meet the industrial requirements of 0.01 defects cm −2 have yet to be developed.The difficulty in obtaining defect-free BCP thin films can be attributed to a lack of understanding and experimental documentation in the early-stage evolution of ordered structures and defects in perpendicular lamellar thin films. Previous studies on the evolution of ordered structures in thin films have focused on the formation of parallel lamellae with island-hole structures, [16][17][18] and late-stage defect dynamics, [9,[19][20][21][22][23][24][25][26] particularly using low-χ or parallel cylinder-forming BCPs. Capturing the real time evolution of perpendicular lamellae in situ has been difficult as BCP selfassembly tends to occur in shorter time frames than most characterization equipment can analyze the thin films and the fact that parallel structures tend to form due to interfacial selectivity at the substrate and free surfaces. However, by utilizing newer technology such as high-speed atomic force microscopy (AFM) equipped with a heating unit for in situ characterization of the annealing process in a wide temperature window from room temperature to above the glass transition temperature (T g ) of the BCP, the self-assembly behavior of BCP thin films can be documented in real time and space. Additionally, although differences in the surface free energies (SFEs) between the BCP components tend to induce the preferential interfacial segregation of one block, by balancing the surface affinities of both blocks or introducing chemically modifying layers to tune the chemical affinities of the interfaces, the selective segregation of one block can be prevented, The evolution of well-ordered, sub-10 nm, perpendicular lamellae from a disordered state is documented directly using in situ atomic force microscopy, cross-sectional scanning electron microscopy, and grazing-incidence small angle X-ray scattering. Since block copolymer (BCP) self-assembly occurs on extremely fast time scales, directly imaging the growth of perpendicular lamellae remains challenging. The lack of understanding behind early-stage self-assembly and how metastable defects can affect the kinetic behavior near thermodynamic equilibrium prevents the realization of defect-free thin films. By characterizing the evolution of nanostructures using a high-χ, perpendicular lamella-forming BCP, poly(polyhedral oligomeric silsesquioxane)-blockpoly(2,2,2...

Further development of next-generation block copolymer (BCP) lithography processes is contingent on comprehensive studies of the ordering dynamics of high-χ BCPs that can form sub-10 nm features on thin films. However, quantitative analyses of the degree of ordering on the surface and cross sections of thin films have been difficult to execute. To tackle this challenge, we employ a perpendicular lamella-forming high-χ BCP, poly(polyhedral oligomeric silsesquixone-block-2,2,2trifluoroethyl methacrylate) (PMAPOSS-b-PTFEMA), and reveal that the high-χ PMAPOSS-b-PTFEMA requires three times the activation energy (E a ) compared to that of poly(styrene-blockmethyl methacrylate) (PS-b-PMMA) for defect annihilation, at E a = 2600 ± 420 kJ mol −1 , and a transition from a fast ordering regime with a growth exponent of Φ = 0.30 at lower orientational order parameters (ψ 2 < 0.36) to a slow ordering regime with Φ < 0.05 at ψ 2 > 0.36, where well-aligned lamellae restrict defect annihilations to enthalpically unfavorable glide mechanisms that require BCP intermixing.

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The real‐time early‐stage evolution of perpendicular lamellae in a high‐χ block copolymer (PMAPOSS‐b‐PTFEMA) thin film is revealed using combinatorial studies including in situ atomic force microscopy (AFM). In article number https://doi.org/10.1002/admi.201801401, Alvin Chandra, Teruaki Hayakawa, and co‐workers directly document the spinodal decomposition and development of short‐range lamellae oriented randomly in three‐dimensions upon self‐assembly.

In the recent years, interest in adapted sports has been growing worldwide. Among them, Boccia is one of the most popular sports that can be enjoyed by all generations, from children to the elderly, as well as people with disabilities (1) . However bedridden people couldn't participate this sport, due to the lack of assistive devices. In this study, we designed and developed a Boccia device which motorizes the normal Boccia ramps so that more people could enjoy Boccia competitions. The device has three elements: "Release mechanism", "Release height control mechanism", and "Azimuth control mechanism". Considering the widespread use of the device, we designed and developed a prototype by simplifying and generalizing the device. After development, we demonstrated the device at three events, and conducted questionnaires to obtain user feedbacks. The results showed that not only people with disabilities but also children and adults tended to enjoy Boccia competitions with this device. This paper reports on this universalized Boccia device.