The cover image, by Bruna A. Bregadiolli et al., is based on the Research Article Towards the synthesis of poly(azafulleroid)s: main chain fullerene oligomers for organic photovoltaic devices, DOI: 10.1002/pi.5419 .
The beam steering mechanism has been a key element for various applications ranging from sensing and imaging to solar tracking systems. However, conventional beam steering systems are bulky and complex and present significant challenges for scaling up. This work introduces the use of soft deployable reflectors combining a soft deployable structure with simple kirigami/origami reflective films. This structure can be used as a macroscale beam steering mechanism that is both simple and compact. This work first develops a soft deployable structure that is easily scalable by patterning of soft linear actuators. This soft deployable structure is capable of increasing its height several folds by expanding in a continuous and controllable manner, which can be used as a frame to deform the linearly stretchable kirigami/origami structures integrated into the structure. Experiments on the reflective capability of the reflectors are conducted and show a good fit to the modeling results. The proposed principles for deployment and for beam steering can be used to realize novel active beam steering devices, highlighting the use of soft robotic principles to produce scalable morphing structures. 相似文献
An analysis of the kinetic azeotropy of the terpolymer from styrene(St)-methyl methacrylate(MMA)-butyl acrylate(BuA) in emulsion polymerization is effectuated. The objective is to determine the conditions for obtaining terpolymers uniform in composition. In this regard, a composition near to the unitary azeotrope is used in batch, semicontinuous and seeded emulsion polymerization processes. As expected, the monomer partition between the different phases modifies the terpolymer composition, in particular at the beginning of the semicontinuous processes. It is also observed that the unitary azeotrope in batch and semicontinuous emulsion polymerization is conserved in a large range of conversion due to the constancy of monomer concentration and radicals in the particle. In this way, a terpolymer with almost an accumulated constant composition is obtained in the seeded process. A thermodynamic analysis of the kinetic azeotropy is also made. The correspondence between the azeotropes of the binary copolymers and the values of the Flory interaction parameters of the monomers χιj is correlated. It is found that the lesser repulsion of the St-MMA pair respect to that of St-BuA provoked that the composition of the terpolymer tends to the copolymer azeotrope of St-MMA.相似文献
α,ω-Hydroxy telechelic poly(ε-caprolactones) were prepared by ring-opening polymerization of the ε-caprolactone catalyzed by ammonium decamolybdate in the presence of different aliphatic diols [HO–(CH2)m–OH, where m?=?2, 4, 6, 8, 10, 12, 14, and 16] as initiators to obtain a family of α,ω-hydroxy telechelic poly(ε-caprolactone) [HO–PCL–O–(CH2)m–O–PCL–OH, m?=?2, 4, 6, 8, 10, 12, 14, and 16]. The content of the alkyl group (AG) (–(CH2)m–) had an important effect on the crystallinity (xi) of α,ω-hydroxy telechelic poly(ε-caprolactone), showing a proportional relationship. In poly(ester-urethanes) derived from α,ω-hydroxy telechelic poly(ε-caprolactones) and 1,6-hexamethylene diisocyanate, the AG also showed a similar effect on the xi and eventually on the mechanical properties, increasing the values of the modulus. Therefore, AG content was a factor to induce a plastic behavior in poly(ester-urethanes). The effect of AG on the water uptake of poly(ester-urethanes) after 1 week was negligible. 相似文献