Conformational Changes and Dynamics during Adsorption of Macromolecules with Different Degree of Polymerization Studied by Monte Carlo Simulations

Novel Cuboid-like Crystalline Complexes (CLCCs), Photon Emission, Fluorescent Fibers, and Bright Red Fabrics of Eu3+ Complexes Adjusted by Amphiphilic Molecules

With the growing needs for flexible fluorescence emission materials, emission fibers and related wearable fabrics with bright emission properties have become key factors for wearable applications. In this article, novel cuboid-like crystals of Eu³⁺ complexes were generated. Except for light-energy-harvesting ligands of thenoyltrifluoroacetone (TTA) and 1,10-phenanthroline hydrate (Phen), the crystal structures were adjusted by other functional amphiphilic molecules. Not only does ETPC-SA, adjusted by stearic acid, have a regular cuboid-like crystal with a size of about 2 μm size, but it also generates the best photon emission property, with a fluorescence quantum yield of 98.4% fluorescence quantum yield in this report. Furthermore, we succeeded in producing novel fluorescent fibers by mini-twin-screw extrusion, and it was easy to form bright red fabrics, which are equipped with strong fluorescence intensity, flexibility, and a smooth hand feeling, with the normal fabricating method in our work. It is worth noting that ETPC-HQ fibers, which carry a crystal complex adjusted by hydroquinone, possess the lowest quantum yield but have the longest average fluorescence lifetime of 1259 µs. This result means that a low-density polyethylene (LDPE) matrix could make excited electrons stand in the excited state for a relatively long time when adjusted by hydroquinone, so as to increase the afterglow property of fluorescent fibers.

Flexible Sensor for Invisible Respiratory Monitoring via Construction of a 2D Stacked Micronetwork

With the advent of 5G and the Internet of Things era, sensitive and stable sensors have begun to develop rapidly, which are important substantial fundaments of smart medical care. In this study, based on the positive temperature coefficient (PTC) in conductive polymer composites (CPC), a novel polyolefin elastomer (POE)/carbon fiber (CF) composite was prepared. By regulating the rheological behavior of the polymer matrix, we realized its controllable thermal expansion in the temperature field and finally realized the reversible construction-destruction of the conductive CF network. Under optimal molecular weight conditions, the POE/CF PTC sensor showed a high sensitivity of 0.11 °C^-1 and stability. It was also demonstrated that the heat transfer efficiency of the composite material played an essential role in the sensitivity of the as-prepared PTC sensor. Most impressively, we have assembled an invisible respiratory monitoring device based on the POE/CF composite to achieve real-time monitoring of human breathing, which displayed wide potential prospects in thermal monitoring and provided good prospects for micron-scale functional composites.