Polythioethers bearing side groups for efficient degradation by E1cB reaction: reaction design for polymerization and main-chain scission.

We have previously reported the polycondensation by the tandem reactions of dithiols and α-(bromomethyl)acrylates, consisting of conjugate substitution (S2' reaction) and conjugate addition (Michael addition) reactions. The resulting polythioethers underwent a main-chain scission (MCS) by E1cB reaction, which is the reverse reaction of conjugate addition, although it was not quantitative due to the equilibrium. Herein, the modification of the structures of polythioethers led to irreversible MCS, whereby the β-positions of ester moieties were substituted with a phenyl group.

A novel electroactive plasticized polymer actuator based on chlorinated polyvinyl chloride gel.

Plasticized poly (vinyl chloride) (PVC) gel is a promising electroactive polymer material for soft actuators and sensors, and it has attracted extensive attention and interest in multi-disciplinary fields. Chlorinated polyvinyl chloride (CPVC) has enhanced mechanical and chemical properties and shows a promising potential for fabricating gel materials for electroactive polymer gel actuators. Thus, we proposed a novel soft actuator based on CPVC gels.

Non-close-packed arrangement of soft elastomer microspheres on solid substrates.

Unlike rigid microparticles, soft and deformable elastomer (rubber) microspheres were found to exhibit a non-close-packed arrangement on solid substrates after the evaporation of water from their dispersions. The microscopic observation revealed that individual microspheres are ordered in regular intervals at the air/water interface of a sessile droplet and remain fixed on the substrate without being affected by the capillary forces during evaporation due to their deformability. Moreover, using the Langmuir-Blodgett method, thin films of non-close-packed structures could be successfully generated over large areas.

Nanostructure and thermoresponsiveness of poly(-isopropyl methacrylamide)-based hydrogel microspheres prepared aqueous free radical precipitation polymerization.

Thermoresponsive hydrogel microspheres (microgels) are smart materials that quickly respond to external stimuli, and their thermoresponsiveness can be tuned by varying the constituent chemical species. Although uniformly sized microgels can be prepared aqueous free radical precipitation polymerization, the nanostructure of the obtained microgels is complex and remains unclear so far. In the present study, the nanostructure and thermoresponsiveness of poly(-isopropyl methacrylamide) (pNIPMAm)-based microgels, which have a volume-transition temperature of ∼43 °C, were evaluated mainly using temperature-controllable high-speed atomic force microscopy.

Surface construction of fluorinated TiO nanotube networks to develop uvioresistant superhydrophobic aramid fabric.

Poor ultraviolet (UV) resistance and good hydrophilicity lead to light aging of aramid fabrics and cause heat damage to the human body. This scenario occurs when the absorbed water by the fabric evaporates and forms high-temperature water vapor in a high-temperature fire environment, which may scald the human body. Herein, a superhydrophobic hollow TNT network structure was built on surfaces of aramid fibers by surface coating fluorinated TiO nanotubes (TNTs) to develop an air-permeable, UV-protective, and superhydrophobic coating.