Search

Polymer-based nanostructures can be generally created by self-assembly of block copolymers that are commonly synthesized by living radical polymerization. In this study, a new strategy is proposed to fabricate block-like copolymers by using the template of binary phase structure of semicrystalline polymers. Poly(vinylidene fluoride) (PVDF) is thermodynamically miscible with an unsaturated ionic liquid (IL) (1-vinyl-3-ethylimidazolium tetrafluoroborate) in the melt and IL molecules are expelled out from the crystalline parts during the crystallization of PVDF. Therefore, the IL molecules are only located at the amorphous region of PVDF crystals. The electron beam irradiation of the IL incorporated PVDF leads to the local grafting of IL molecules onto the PVDF molecular chains in the amorphous region, so block-like grafting polymer chains of crystalline PVDF-b-(amorphous PVDF-g-IL)-b-crystalline PVDF can be achieved. The subsequent heating of the irradiated sample induces the microphase separation of PVDF-g-IL from the ungrafted PVDF chains., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Highlights: Precise exfoliation and modification of nano-Tellurium was realized by adopting a room-temperature ionic liquid as the electrolyte. Nano-Tellurium with high-entropy morphology can offer greater solar absorption and more kinds of surface chemical groups, giving rise to superior photothermal properties. Nano-Tellurium-poly(vinyl alcohol)-based photothermal foam hydrogels, with high compressibility, excellent water transport rate and low evaporation enthalpy of water, combined with a new heat-supply model, achieve an evaporation rate of 4.11 kg m−2 h−1 with energy efficiencies up to 128% under 1 sun irradiation, which are the highest values for semiconductor-based nanocomposites reported so far. The development of tellurium (Te)-based semiconductor nanomaterials for efficient light-to-heat conversion may offer an effective means of harvesting sunlight to address global energy concerns. However, the nanosized Te (nano-Te) materials reported to date suffer from a series of drawbacks, including limited light absorption and a lack of surface structures. Herein, we report the preparation of nano-Te by electrochemical exfoliation using an electrolyzable room-temperature ionic liquid. Anions, cations, and their corresponding electrolytic products acting as chemical scissors can precisely intercalate and functionalize bulk Te. The resulting nano-Te has high morphological entropy, rich surface functional groups, and broad light absorption. We also constructed foam hydrogels based on poly (vinyl alcohol)/nano-Te, which achieved an evaporation rate and energy efficiency of 4.11 kg m−2 h−1 and 128%, respectively, under 1 sun irradiation. Furthermore, the evaporation rate was maintained in the range 2.5–3.0 kg m−2 h−1 outdoors under 0.5–1.0 sun, providing highly efficient evaporation under low light conditions. [ABSTRACT FROM AUTHOR]

Transparent polymeric materials withhigh ductility and antistaticproperties have attracted much attention. A room temperature ionicliquid (IL), tributyl(methyl)ammonium bis(trifluoromethane)sulfonylimide([tbmam+][Tf2N–]), was integratedinto polycarbonate (PC), to fabricate optically transparent antielectrostaticcomposites by melt processing. The morphology and physical propertiesof the composites were investigated. Differential scanning calorimetryand dynamic mechanical analysis indicated the depression of the glasstransition temperatures of the PC/IL composites, compared with thatof neat PC. This indicated the interaction between PC and the IL.Transmission electron microscopy indicated that the IL was highlycompatible with PC, at low IL loadings. This resulted in enhancedantielectrostatic properties, and significantly improved elongationat break of the PC/IL composites. The PC/IL composites maintainedthe high transmittance of PC. In addition, the PC/IL composites withhigh clearance and antielectrostatic properties could be achievedby large-scale continuous melt extrusion, indicating that the methodto fabricate both optically transparent and antielectrostatic compositeis feasible for industrial application. [ABSTRACT FROM AUTHOR]

The impact of pristine multiwalled carbon nanotubes (MWCNTs),anionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate[BMIM][PF6], and the ionic liquid-modified MWCNTs (IL-MWCNTs)on the crystallization behavior of melt-crystallized poly(vinylidenefluoride) (PVDF) has been investigated. Pristine MWCNTs accelerate crystallization of PVDF as an efficient nucleation agent, while theformed crystals are mainly nonpolar α crystal form with fewpolar β crystals. Incorporation of only ionic liquid resultsin depression of the PVDF melt crystallization rate due to the miscibilityof IL with PVDF but leads to a higher content of polar crystals (βand γ forms) than MWCNTs. The ionic liquid and MWCNTs show significantsynergetic effects on both the nucleation and the formation of polarcrystals for PVDF by melt crystallization. Addition of IL-MWCNTsnot only improves the MWCNTs dispersion in PVDF matrix but also increasesthe overall crystallization rate of PVDF drastically. More important,the melt-crystallized PVDF nanocomposites with IL-MWCNTs show 100%polar polymorphs but no α crystal forms. To the best of ourknowledge, this is the first report on the achievements of full polarcrystal form in the melt-crystallized PVDF without mechanical deformationor electric field. The IL to MWCNTs ratio and the IL-MWCNTs loadingcontent effects on the crystallization behavior of PVDF in the nanocompositeswere also studied. It is considered that the specific interactionsbetween >CF2with the planar cationic imidazolium ringwrapped on the MWCNTs surface lead to the full zigzag conformationsof PVDF; thus, nucleation in polar crystals (β and γforms) lattice is achieved and full polar crystals are obtained by subsequent crystal growth from the nuclei. [ABSTRACT FROM AUTHOR]