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Polymer nanocomposites with excellent electromagnetic interference (EMI) shielding and thermal conductivity (TC) are urgently needed to solve the increasingly serious electromagnetic pollution and heat accumulation in devices. Herein, a distinct strategy was proposed to improve the dispersity of graphene nanoplatelets (GNPs) and integrate cellulose nanofiber (CNF), graphene nanoplatelets (GNPs), and MXene into a layered structure. The presence of MXene can improve the dispersity of GNPs, and the presence of GNPs can protect MXene from oxidation. By combining the excellent electrical conductivity of MXene and the high thermal conductivity of GNPs, the CNF/GNPs/MXene composite films exhibit excellent EMI shielding performance and high in-plane thermal conductivity. The electromagnetic shielding property of the CNF/GNPs/MXene composite films reaches 33.74 dB and the in-plane TC is 8.55 W/(m·K) when the total filler content is 50 wt % while the thickness of the composite film is only 38.5 μm. In addition, the mechanical properties of the composite membrane can meet general requirements. Therefore, these ultrathin CNF/GNPs/MXene composite films show great application potential as effective EMI shielding and thermal management materials.

Super‐toughened poly(l‐lactic acid) (PLLA) was prepared by reactive blending of PLLA with poly(ϵ‐caprolactone) (PCL), glycerol and 4,4′‐methylenediphenyl diisocyanate. The reactive interfacial compatibility between PLLA and the formed crosslinked polyurethane (CPU) in the PLLA matrix was studied in detail. The morphology and the toughness of the blends can be tuned by changing the CPU content. The results indicate that the impact strength of PLLA shows a tendency to higher values with the increasing PCL content up to 20 wt%. The notched impact strength of the blend with 20 wt% PCL increases to 55.01 kJ m−2, which is 24.9 times higher than that of neat PLLA. The elongation at break is also increased from 5% to 139.4%, indicating the brittle − ductile transition. The increased interfacial binding strength through the reactive interfacial compatibility and the formation of a CPU network in the PLLA matrix account for the improved toughness of PLLA/CPU blends. Dynamic mechanical analysis results indicate that the compatibility between PLLA and CPU is improved with increasing CPU content resulting in the formation of more interfacial phase. In addition, rheological property measurements indicate that the improvement in storage modulus and complex viscosity is ascribed to the formation of a CPU network in the PLLA matrix. © 2016 Society of Chemical Industry

Aromatic groups are introduced into the end peripherals of polyhedral oligomeric silsesquioxane (POSS) core-based organic/inorganic hybrid supramolecules to get a novel dendrimer gelator POSS-Z-Asp(OBzl) (POSS-ASP), which have eight aspartate derivative arms to make full use of strong π-π stacking forces to get strong supramolecular gels in addition to multiple hydrogen bindings and van der Waals interactions. POSS-ASP can self-assemble into three-dimensional nanoscale gel networks to provide hybrid physical gels especially with strong mechanical properties and fast-recovery behaviors. Two totally different morphologies of the connected spherical particle structures and banded ultralong fibers are observed owing to the polarity of solvents confirmed by the scanning electron microscopy, polarized optical microscopy, and transmission electron microscopy techniques, expecting the existing various self-assembly models and illustrating the peripherals of the dendrimer and the polarity of solvents having huge influences in the supramolecular self-assembly mechanism. What is more, the thermal stability, rheological properties, and network architecture information have also been investigated via tube-inversion, rotational rheometer, and powder X-ray diffraction methods, the results of which confirm the two different gel formation mechanisms that make POSS-ASP to exhibit two totally different thermal and mechanical properties. Such a study reports a new gelation system in organic or organic/aqueous mixed solvents, which can be helpful for investigating the relationship of dendritic supramolecular gelation and different polarity solvents during the supramolecular self-assembly process of gelators.

A kind of body temperature controlled optical and thermal information storage light scattering display based on super strong liquid crystalline physical gel with special "loofah-like gel network" was successfully prepared. Such liquid crystal (LC) gel was obtained by mixing a dendritic gelator (POSS-G1-BOC), an azobenzene compound (2Azo2), and a phosphor tethered liquid crystalline host (5CB), which could show its best contrast ratio at around human body temperature under UV light because of the phosphor's fluorescence effect. The gel also has quite strong mechanical strength, which could be used in wearable device field especially under sunlight, even under the forcing conditions as harsh as being centrifuged for 10 min at the speed of 2000 r/min. The whole production process of such a display is quite simple and could lead to displays at any size through noncontact writing. We believe it will have wide applications in the future.

The fully biobased flame retardant, which is based on the green and convenient ionic reaction of phytic acid (PA) and taurine (TA) in water, brings flame retardancy to polylactic acid (PLA) efficiently. PLA composite passes UL-94 V-0 rating in vertical combustion successively with only 0.5 wt % reactant of PA and TA (PA-TA). Moreover, the peak heat release rate (PHRR) and the total heat release rate (THR) of PLA composite are reduced by 13.1 and 10.0% with 5.0 wt % PA-TA. Moreover, the elongation at break of PLA with 5.0 wt % PA-TA is 92.7% higher than that of pure PLA due to the ultralow addition and the interaction of hydrogen bonds between the flame retardant and the matrix material. The resultant fully biodegradable flame-retardant PLA composites reported here could be widely applied in electronic appliances, automobiles, and other fields.